| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|
|
Fire Prevention Code of Petrochemical Enterprise Design
2.1.2 The classification of fire-hazard for liquefied hydrogen-carbon (LHC) and combustible liquid (CL) shall be in compliance with following stipulations:A. The classification of fire-hazard for liquefied hydrogen-carbon, combustible liquid shall be divided in accordance with Table 2.0.2.;
B. The classification of fire-hazard for Class B liquid when the operating temperature is above the flash point shall be regarded as Class AII liquid;
C. The classification of fire-hazard for Class C liquid when the operating temperature is above the flash point shall be regarded as Class BI liquid.
Table 2.0.2 Classification of Fire-hazard for Liquefied Hydrogen-carbon and Combustible Liquid
For examples of classification of fire-hazard for liquefied hydrocarbon, combustible liquid, see Appendix C.
2.1.3 The classification of fire-hazard for combustible solid shall be divided in accordance with the relevant stipulations in the current state standard Code for Design of Building Fire Protection.For examples of classification of fire-hazard for Class A, B, C solid, see Appendix D.
3 Area Classification and Plant Overall layout3.1 Area Classification3.1.1 During area classification, the characteristics of the petrochemical enterprise, the adjacent plant or facilities, as well as the fire-hazard, shall be comprehensively considered and arranged rationally, considering the-top graphical features and wind direction, etc.3.1.2 The production area of petrochemical enterprise should be arranged in the up-wind side of adjacent city and town, or residential area where there is the least frequency wind-direction whole year.3.1.3 In mountainous region or hilly region, the production area of petrochemical enterprise shall be avoided to be placed in the stuffy locations.3.1.4 In case of arranging petrochemical enterprise along the embankment of river, it should be placed in the downstream of the adjacent city and town, important bridge. large-sized building or structure.3.1.5 In case of arranging tank farm for liquefied hydrocarbon or combustible liquid along the embankment of river or sea-shore, the leakage proofing measure shall be taken to prevent the combustible from leaking into waters.3.1.6 Highways, provincial overhead power-supply cable must not pass across production area; and the regional flood drainage ditch, should not pass through production area.3.1.7 Fire-distance between petrochemical enterprise and the adjacent plants or facilities shall not be less than the requirements in Table 3.1.7.Definition of the starting point and ending point for fire-distance shall be in compliance with the requirements of Appendix.F.
The fire-distance for elevated flare shall be determined through heat radiation calculation; the fire-distance for elevated flare which may entrain combustible liquid, shall not be less than the requirements in Table 3.1.7.
Table 3.1.7 Fire distance for petrochemical enterprise to adjacent plants or facilities (m)
Note:
(1) The statement in the brackets refer to the starting/ending point.
(2) In case the adjacent facility is the on-shore part of a harbour, warehouse or stockyard of very important goods, military facilities, airport etc., which has special requirement on the fire-distance for petrochemical enterprise, relevant (stipulations) shall be adhered to.
3.2 Overall Layout3.2.1 The overall layout shall be carried out and collectively arranged in area by class and function in accordance with the characteristics of process, the production steps and fire-hazard of the component, considering the topographical features, wind direction and other concrete conditions meantime.3.2.2 Process units, tank groups, loading facilities or plant waste water treatment facilities in which combustible gas may set off possibly, should be arranged in the upwind of staff-gathering locations, and direct firing or sparkle sending-out position, where there is the least frequency wind direction in whole year; In the mountainous region or hilly region, it should be avoided to be arranged in stuffy locations.3.2.3 LPG tank groups, combustible liquid tank groups shall not be arranged adjacently on the stage above process unit, plant important facility or staff-gathering location; however, in case restricted by concrete conditions or when there is specific process requirements, combustible liquid feedstock tank may be arranged adjacently on the stage above process unit.3.2.4 In case a plant is arranged by levels, leakage-proofing measures shall be taken to avoid combustible liquid from overflowing.3.2.5 LPG tank group or combustible tank group should not be arranged close to the flood drainage ditches.3.2.6 Air separation unit shall be arranged in clean atmosphere block, and in the up wind of the location setting off ethylene, hydro-carbon gas, flying dust etc., where there is the least frequency wind direction in whole year.3.2.7 Plant elevated flare should be located at the upwind side of production area where there is least frequency wind direction in whole year.3.2.8 Truck loading station, LPG filling station, Class A warehouse and other facilities where vehicles come and go frequently, shall be arranged in the boundary of plant or off-site and should be separated by enclosure fence to form an independent area.3.2.9 Plant power substation, in which cable line comes into and goes out of factory by overhead, shall be arranged in the boundary of the plant.3.2.10 In-site landscaping shall be in compliance with following stipulations.A. The tree sort with high-resin shall not be selected to plant in production site, and the sort with high water content should be preferred.
B. The sort of green fence, or densely bushes should not be planted between process units or combustible gas tank groups, liquefied hydrocarbon tank groups combustible liquid tank groups and the fire vehicle access in the neighborhood;
C. In side fire-dike for combustible liquid tank, not more than 15cm high ever-green grass with high water content may be designed to plant on the land.
D. Landscaping must not be designed in fire-dike of liquefied-hydro-carbon tank groups.
E. In-site landscaping shall not affect the fire-fighting operation.
3.2.11 The fire-distance of petrochemical enterprise in overall layout, unless specified otherwise, shall not be less than that stipulated in Table 3.2.11. The fire-distance between process units or facilities (excluding tank groups), shall be determined based on the closest equipment, buildings or structures. For the definition of starting/ending point for fire-distance calculation shall be in compliance with Appendix F.The fire-distance of elevated flare shall be determined through heat radiation calculations, for flare which may entrain combustible liquid, the fire-distance shall not be less than that specified in Table 3.2.11.
Table 3.2.11 Fire Distance of Overall Plot Plan for Petro-chemical Enterprise
Note of Table 3.2.11
(1) Fire-distance between tank groups and other facilities is determined based on the tank with the biggest volume;
(2) The numerator is applicable for petrochemical units, whose fire-distance is determined in accordance with the class of the adjacent side; and the denominator is applicable for refinery units.
(3) In case the product of one unit goes directly to other unit, the fire-distance in-between can be reduced, but not less than 15m; or not less-than 10m for Class C units. Complex unit can be considered as a single unit, the fire-distance of equipment, buildings shall be implemented in accordance with Clause 4.2.1 of the code. For examples of classification of fire-hazard for process plants or units inside plants, see Appendix E.
(4) In case process plants or facilities which possibly set off combustible gas are arranged adjacently with direct-firing furnace of process plant, the fire-distance shall be determined as to the location direct firing.
(5) For independent power transformer and distributing substation, work-shop office, etc., the distance can be reduced by 25% (excluding flare).
(6) For tank with unit volume at or below 1000 m3, it may be reduced by 25%; for tank with unit volume above 5000 m3, it shall be increased by 25% (excluding flare).
(7) For Class C liquid, the distance can by reduced by 25% (excluding flare).
(8) This case includes warehouse of filled cylinders of combustible gas, or combustion-supporting gases. For ware-house (shelter, stockyard) storing Class B, Class C goods, it may be decreased by 25%; for stockyard of Class C combustible solid, it can by reduced by 50% ( apart from flare).
(9) The fire-distance between tank groups and its special-use pump house is as following: Class AI, it shall not be less than 15m; for Class AII, C, it shall not be less than 12m; for floating-roof tank groups, Class C tank groups, not less than 10m (for tank with volume at or below 500m3, it shall not be less than 8m).
(10) For emergency liquid basin, the fire-distance can be determined as for wastewater treatment unit.
(11) The figure is only applicable for diesel locomotive, for stream-driven locomotive, it shall be increased by 25% (excluding flare).
(12) See the text of the Clause.
3.3 In-site Road3.3.1 The quantity of main exits of a factory shall not be less than two, and should be located at different orientation.3.3.2 The roads of two or more main exits shall be avoided to at grade intersect with the same railway; in case have to intersect with at-grade, the distance of two roads shall not be less than the length of the longest train passing the railway at least; otherwise, another separate fire vehicle road shall be designed.3.3.3 For main road and its off-site extension section, it shall be avoided to at-grade intersect with in-site railway where there is frequently adjustment for train or with adjacent off-site railway.3.3.4 In the production area, double lane way should be adopted; in case adopting single-lane road, the truck passing requirements shall be met.3.3.5 For process units, tank farms, combustible loading blocks and its warehouse, loop fire-vehicle access shall be designed; in case restricted by topographical conditions, the dead end fire vehicle access with turning-round yard may be acceptable also.3.3.6 The distance between tanks inside tank farm for liquefied hydro-carbon combustible liquid and fire vehicle access, shall be in accordance with following specifications.A. The distance to two different orientation fire access from the centerline of any tank shall not be more thank 120m;
B. In case there is only one fire vehicle access on one side, the distance of the access to the centerline of tanks shall not be more than 80m;
3.3.7 In the train loading area for liquefied hydrocarbon, combustible liquid, a fire vehicle access parallel with main railway shall be considered, and the following requirements shall be met:A. In case there is only one fire vehicle access on one side, the distance between the access and its farest railway shall not be more than 80m;
B. In case there are two fire vehicle access in both sides, the distance of the two accesses shall not be more than 200m; otherwise, one more fire vehicle access shall be added in between.
3.3.8 In case the top of the road is more than 2.5m above the adjacent ground and there are process plants, tanks of combustible gas, hydro-carbon, combustible liquid in the range of 15m from the road-edge, safeguard facilities such as fender-pier and dwarf-wall shall be furnished on the road edge in this section.3.4 In-site Railway3.4.1 In-site railways shall be arranged collectively at the boundary of the factory.3.4.2 Train loading block for solid good inside process units may be arranged at the boundary of warehouse or stockyard.(basin)3.4.3 In case the loading platform for liquefied hydrocarbon is arranged in the same loading block with that for combustible liquid, the platform for liquefied hydrocarbon shall be in one side of the block.3.4.4 In side train loading area for liquefied hydrocarbon, combustible liquid, the distance from diesel locomotive to pick-arm of another platform shall meet following requirementsA. The distance shall not be less than 12m for Class A, B loading-arm;
B. The distance shall not be less than 8m for Class C liquid.
3.4.5 In case the train loading lane for liquefied hydrocarbon, combustible liquid, Class A, B solid good, is dead end, the distance from train stop to the last loading seat shall not be less than 20m.3.4.6 The train loading lane for liquefied hydrocarbon, combustible liquid, shall not be served as passage lane.3.4.7 The parking section of train loading lane for liquefied hydrocarbon, combustible liquid shall be even and straight, In case restricted by topographical conditions, it may be designed at the ramp section with the radius not less than 500m.3.4.8 In the train loading block for Class A, B, C, the fire-distance between two adjacent loading-arms shall not be less than 10m; but for Class C combustible liquid, it may not be less than 7m;3.5 In-site Pipe Route3.5.1 Pipeline paved on the ground or on low pipe-support shall not be arranged all around process plants or around tank groups.3.5.2 For pipe-line and its pipe-rack passing over in-site railway, the clearance shall not be less than 5.5m; in case passing in-site vehicle access, it shall be not less than 5m.3.5.3 In case pipe-line conveying combustible gas, liquefied hydrocarbon, combustible liquid passes underground across railway or road, it shall be placed in duct or inside jacket pipe.3.5.4 The combustible gas, liquefied hydrocarbon, combustible liquid pipeline shall not pass overhead or underground across irrelevant refinery plants, chemical production units or facilities; but it may pass over pump house (shelter) of tankfarm. In this case, valves, flanges, threaded expansion joints shall not be placed on the pipe segment above pump-houses (or shelters).3.5.5 &, nbsp; For the pipe-trench, cable duct, cable channel in the range with radius of 30m from the equipment which sets off heavier-than-air combustible gas Specific Gravity than air, measures shall be taken to prevent combustible gas from getting into or accumulating.3.5.6 Various process pipelines or waste water pipelines containing combustible liquid, shall not be paved over or under the road surface or road shoulders.3.5.7 The pipe-supports, lighting pole, walkway tree or indication pole placed on public type road shoulders shall meet following requirements.A. The distance to the pavement edge of double lane road shall not be less than 0.5m;
B. The distance to the pavement edge of single lane road shall not be less than 3m.
4 Process Plant4.1 General4.1.1 Process equipment (herein after called equipment for short), pipe and component material shall be in accordance with following requirements:A. equipment body (excluding lining ) and its foundation, pipe (excluding lining), pipe support and its foundation shall be of non-combustible material, but for oil tank bottom pad, asphalt sand may be adopted.
B. The insulation layer for equipment and pipe shall be of non-combustible material. In case foam plastic used as cold-insulation for equipment and pipe, it shall be of fire-retardant material and the oxidation index shall not be less than 30;
C. The buildings, structures shall be of non-combustible material, the fire-resistance duration shall be in compliance with relevant clause of current state standard “Code for Design of Building Fire Protection”.
4.1.2 For equipment and pipe, suitable instruments, alarms, automatic inter-lock protection systems and emergency shut-down systems shall be designed based on the fire-hazard characteristic of inside material at operation conditions.4.1.3 The fire-protection design of buildings not stipulated by the code shall be implemented in accordance with the relevant previsions of current standard “Code for Design of Building Fire Protection”.4.2 In-site Layout4.2.1 The fire-distance of equipment, buildings unless specified in the code shall not be less than the specification in Table 4.2.1.4.2.2 To avoid coking and plugging, to control temperature-drop, pressure-drop and by-reaction, and/or due to other process requirements, the relevant equipment may be arranged near each other.4.2.3 The overhead condensers, bottom-reboilers and fractionator, the separators, inter-coolers, receivers and compressor, other accessories close relevant with main equipment can be arranged by direct connection or near to principal equipment.4.2.4 For dewaxing unit or deoiling unit of ketonization-benzene plants, the distance between inert gas generator and its kerosene storage tank may be determined in accordance with process requirements; but it shall not be less than 6m.4.2.5 For direct-firing furnace, the distance to its accessory fuel-gas separator and heater etc. shall not be less than 6m.
Table 4.2.1 Fire Distance of Overall layout for Equipment and Buildings (m)
Note:
(1) 250℃ is assumed if the ignition point is unavailable
(2) the fire-distance for combustible gas compressor with unit drive power less than 150kW may be determined as for “the other process equipment” in which the medium temperature is below ignition point.
(3) the maximum volume of intermediate storage tank shall be in accordance with Clause 4.2.28. The fire-distance may be determined as for “other process equipment” in which the medium temperature is below ignition point on the condition that the unit volume of storage tank is less than 50m3 for liquefied hydrocarbon, 100m3 for combustible liquid, 200m3 for combustible gas. The fire-distance between intermediate tank and electric demineralization tank or dewatering tank shall not be less than 9m. The fire-distance of intermediate tank shall be in compliance with the relevant specification in Chapter 5.
(4) The water pond and oil separation pond containing combustible liquid can be determined in accordance with the specifications of “other process equipment” in which the medium temperature is below ignition point.
(5) the fire-distance for Class CII liquid equipment is not specified.
(6) the fire-hazard classification of equipment shall be determined by the fire-hazard classification of materials that are handled, stored or transported. The fire-hazard classification of buildings shall be determined by the highest fire-hazard class of the equipment in the buildings.
4.2.6 For the formulating tank with total volume over 800m3, which is applied for polymerization liquid mixture by solution process using Class AII, Class BI liquid as solvent, the fire-distance to the adjacent equipment, building should not be less than 7.5m; in case the total volume of the storage tank is less than or equal to 800m3, the fire-distance is not specified.4.2.7 The primary instrument room of online analysis for combustible gas, liquefied hydrocarbon, combustible liquid, the fire-distance to process equipment is not specified.4.2.8 The room or box of on-line analysis primary instrument placed in explosive and hazardous locations shall be ventilated by force.4.2.9 Complex unit can be considered as a single unit, the equipment, buildings, shall be in accordance with Table 4.2.1.4.2.10 Equipment shall be placed in the open-air or semi-open-air, and the extent of explosion hazardous locations shall be reduced. The extent of explosion hazardous locations shall be determined in accordance with the current state-standard “Code for Design of Electrical Installation in Explosion-hazardous and Fire-hazardous Locations”.In case required by process or restricted by nature conditions, some equipment may be placed in-doors.
4.2.11 Inside plant, the occupancy area shall be divided into several blocks for equipment and building with not more than 10000m2 by road partition.For synthetic fiber plants, in case the occupancy area of resinification unit, polymerization unit and after-processing unit is more than 10000m2，fire access shall be designed along the both sides.
4.2.12 For fire vehicle access inside plant, the design shall be in accordance with following requirements.A. Inside plant, passing-through road shall be installed unless the width of plant is less than or equal to 60m and there exist fire vehicle accesses outside plant, the road can be saved.
B. The road width shall not be less than 4m, the overhead clearance for the road shall not be less than 4.5m.
4.2.13 Equipment, buildings, structures should be arranged at the same level; in case restricted by topographical conditions, the control room, substation, laboratory, living room and so on shall be arranged at higher level; inter-mediate storage tank shall be arranged at lower grade.4.2.14 Direct-firing furnace and oven shall be arranged together at the plant boundary, and at the down-wind of equipment involving combustible gas, liquefied hydrocarbon, Class AII liquid where there is the least frequency wind direction in whole year.4.2.15 In case there is non-combustible solid partition wall between direct-firing furnace and outdoor liquefied hydrocarbon equipment, the fire-distance can be less than that specified in Table 4.2.1, but not less than 15m. The solid wall should not be less than 3m high, and not more than 5m away from furnace, and shall be possible to prevent combustible gas getting into furnace; in case the wall orientating to direct-firing furnace for liquefied hydrocarbon equipment house or Class A combustible gas compressor house is closed enclosure wall, the fire-distance can be less than that specified in Table 4.2.1, but not less than 15m.4.2.16 In case one room shared by equipment with different classes of fire-hazard, the classification of the room shall be determined based on the equipment with the highest fire-hazard classification. However, when the percentage of equipment with higher fire-hazard classification is less than 5% and the fire is not enough to spread to other locations or can be prevented from spreading in case of fire accident, the classification of the room can be determined based on the equipment with lower fire-hazard class.4.2.17 In case one building shared by rooms with different fire-hazard class, the in-between partition wall shall be fire wall.4.2.18 In a building, the staff-gathering rooms shall be arranged in the end with lower fire-hazard class.4.2.19 In case a room involved with Class A, Class BII is adjacent with one room where sparkle likely gives off, the distance of doors or windows shall be in accordance with current state standard “Code for Design of Electrical Installation in Explosion-hazardous and Fire-hazardous Locations”.4.2.20 Plant control room, power transformer and distribution substation, laboratory room, office building and living room, etc. shall be arranged at one side of plant and outside of the range of explosion hazardous area also, and should be in the down-wind of Class A equipment where there is the least frequency wind direction in whole year.4.2.21 The arrangement of plant control room, power transformer and distribution substation, laboratory room shall be in accordance with following:A. Control room, power transformer and distribution substation should be arranged on the first floor of buildings; in case required by process or restricted by other conditions, control rooms, power transformer and distribution substation may be arranged on the second floor or higher.
B. Inside the plant releasing heavier-than-air combustible gas, the indoors grade of control room, power transformer and distribution substation, and laboratory room shall be 0.6m higher above the outdoors grade.
C. In case one lateral-wall of control room, power distribution and substation, laboratory room towards Class AI intermediate storage tank is closed enclosure wall, the fire-distance may be less than the specification in Table 4.2.1, but shall not be less than 15m.
D. The primary instrument of the on-line analyzer for combustible gas, liquefied hydro-carbon, combustible liquid must not be arranged inside control room or laboratory room; in case the above said instruments are placed in the room adjacent to the control rooms, laboratory rooms, the partition wall shall be fire-proofing.
4.2.22 The control rooms or distribution rooms with voltage less than 10 kV exclusively used for compressors or pumps can be arranged in the same buildings with the compressor house, pump house and etc.; but the doors and windows of the rooms shall be located outside the extent of fire-hazardous zone.4.2.23 The control room for two or more units in a complex plant, the fire-distance to the Class A, Class BI or direct-firing equipment shall not be less than 30m.4.2.24 The design of combustible gas compressor arrangement and its house shall be in accordance with following:A. The combustible gas compressor should be arranged in a open or semi-open house.
B. Class A combustible gas compressor house with unit power at or above 150 kW should not be arranged in the same building with other Class A, B and C house; Class A, B and C equipment must not be placed above the compressors, which is not subject to self-furnished lube-oil console.
C. On the ceiling of the open house or semi-open house for lighter-than-air combustible gas compressor, forced ventilation measures shall be adopted.
D. Grated plate should be adopted for part of the compressor house floor for lighter-than-air combustible gas.
E. On the ground of compressor house for heavier-than-air combustible gas, trench or ditch shall not be designed; if existing trenches or ditches, measures shall be taken to prevent gas from accumulating. At the bottom of lateral wall, ventilation device shall be installed.
4.2.25 Liquefied hydro-carbon pump, combustible liquid pump shall be arranged in open-air or semi-open-air. In case placed inside closed pump house, the design of hydro-carbon pump, combustible liquid pump and its house shall be in compliance with following:A. Liquefied hydro-carbon pump, and combustible liquid pump with the operating temperature at or above flash point shall be arranged in different room from combustible liquid pump with the operating temperature below flash point; the in-between partition wall shall be fire-proofing.
B. For combustible liquid pump house with the operating temperature at or above flash point, the distance of the doors and windows to that for Class AI, Class BI combustible liquid pump house with the operating temperature of below flash point shall not be less than 4.5 m.
C. On the ground of Class A, BI liquid pump house, trenches or ditches shall not be designed; at the bottom of lateral-wall, ventilation device shall be installed.
D. In side the liquefied hydro-carbon pump house, above the combustible liquid pump with the temperature at or above the ignition point, Class A, B and C buffers shall not be placed.
4.2.26 The pressure vessels with the operating pressure higher than 3.5 MPa should be arranged in one end or one side of the plant; the high-pressure and super-pressure reaction equipment with explosion hazard should be arranged inside the explosion proofing structures.4.2.27 Air coolers should not be placed above the combustible liquid equipment with the operating temperature at or above the ignition point; in case have to be placed on the above, partition slab of non-combustible material shall be adopted for partition and protection.4.2.28 In side of plant, the total volume of intermediate liquid hydrocarbon storage tank should not be more than 100 m3; and the total volume of intermediate combustible gas or combustible liquid should not be over 1000 m3.The fire requirements for intermediate storage tank shall be in accordance with the relevant requirements of Chapter 5.
4.2.29 In side the plant, the loading facilities, storage room and so on for alkyl-metal oxide, organic super-oxide and other Class A hazardous chemicals shall be arranged in the boundary of plant.4.2.30 Combustible gas cylinders and combustion-supporting gas cylinders (including full cylinder and empty cylinder) shall be stored respectively in open shelters located at the boundary of the plant, and shall be far away from direct-firing equipment or equipment with the operating temperature at or above ignition point.4.2.31 The emergency exits of buildings shall be open towards outside. The number of emergency exits for Class A, B and C buildings shall not be less than two; but for the room with the area less than 60 m2 for equipment involving Class BII, Class C liquid, one emergency exit may be acceptable.4.2.32 The emergency exit of equipment structures or platforms shall be in compliance with following:A. For the platform inside column blocks for combustible gas, liquefied hydro-carbon, combustible liquid, and other equipment platform, not less than two ladders to ground shall be installed as safety emergency access; but for Class A gas, or Class A, Class BI liquid equipment platform with the length not more than 8 m, or for Class BII and Class C liquid equipment platform with the length not more than 15 m, one ladder can be acceptable.
B. The adjacent structures and platforms can be connected by bridge, and the bridge connected to adjacent platform can serve as one safety access.
C. The distance of adjacent safety accesses shall not be more than 50 m.
4.2.33 Around the equipment where there is a chance for combustible liquid to leak and overflow during start-up and shut-down or maintenance, a dike of not less than 150mm high and draining devices shall be installed.4.3 Process Piping4.3.1 Pipelines for combustible gas, liquefied hydro-carbon and combustible liquid shall be connected by weld unless required to be flanged. For NPT thread connection for above said pipes and valves with nominal diameter equal to or less than 25 mm, unless pipe serving for hydrogen-fluoride acid and other corrosive medium which may result in crevice corrosion, seal weld shall be made on the thread position.4.3.2 Pipelines for combustible gas, liquefied hydro-carbon and combustible liquid shall not pass through irrelevant buildings.4.3.3 Sampling tubes for combustible gas, liquefied hydro-carbon and combustible liquid shall not be led into chemical analysis room.4.3.4 Pipelines for combustible gas, liquefied hydro-carbon and combustible liquid shall be placed over-head or paved along the ground. In case having to be paved in pipe-trenches, measures shall be taken to prevent gas and liquid from accumulating in the pipe trenches, and the trenches shall be hermetically isolated from outside at the factory house; the waste water in the pipe-trenches shall be drained to production waste water header after hydraulic seal pot.4.3.5 In case process pipelines and utilities pipelines are paved on one multi-story pipe-rack, the pipelines with the medium temperature at or above 250℃ should be placed on the top story; and the pipelines serving for liquefied hydro-carbon and corrosives should be on the bottom story; for the pipelines which have to be placed on the bottom story, in case the temperature of the medium is at or above 250℃, it can be placed on the outer side, and shall not be adjacent with liquefied hydro-carbon pipelines.4.3.6 In case on the same pipe-rack with pipelines for combustible gas, liquefied hydro-carbon and combustible liquid, the oxygen pipeline shall be placed on one side, and should be partited from above said pipes with utilities pipelines in-between, or kept 250mm clearance away from above said pipelines.4.3.7 In case utilities pipelines are connected with pipelines or equipment handling combustible gas, liquefied hydro-carbon and combustible liquid, following requirements shall be met:A. On continuously operated utilities pipelines, check valve shall be installed and stop valve shall be installed on the foot of branch-out pipe.
B. On intermittently operated utilities pipelines, double stop valves shall be installed and one examination valve shall be installed between two stop valves.
4.3.8 On the lowest point of continuously operated combustible gas pipelines, double drain valves shall be installed, and the drained out liquid shall be collected into a close system; for the drain valve which are not operated but during start-up and shutting-down, one single valve with thread plug or blind may be acceptable.4.3.9 For combustible gas compressors, centrifugal combustible liquid pump, in case the back flow of medium can result into accident during abnormal conditions such as power failure, steam supply cut-off, etc., check valve shall be installed on the discharge lines.4.3.10 For heating furnace, in case the pressure prior to fuel gas control valve is at or below 0.4 MPa (G) and there is no low-pressure self-protection instruments, fire arrestors shall be installed on fuel-gas pipelines between each control valve and furnace.4.3.11 The condensate in the separator on fuel gas lines for heating furnace shall not be discharged open.4.3.12 For plant in-coming and out-going lines of combustible gas, liquefied hydro-carbon and combustible liquid, block valve and spectacle blind shall be installed at the boundary of the plant, where an operating platform shall be designed; if the platform is at or above 8m long, two ladders shall be installed in two direction.4.4 Pressure Relief4.4.1 Safety valve shall be installed on the following equipment which may likely be over-pressured under abnormal conditions:A. Pressure vessel with the top operating pressure above 0.7 MPa;
B. Distillation column, evaporation column and stripping column with the top pressure (apart from the stripping column in which the vapor is directed from the top to other distilling column) above 0.03 MPa;
C. At the discharge of every stage of reciprocating compressor or the discharge of electric-driven reciprocating pump, gear pump, screw pump, and other positive displacement pump (excluding the equipment furnished with safety valve).
D. Whenever the equipment connected with the discharge of blower, centrifugal compressor, centrifugal pump or steam-driven reciprocating pump, cannot bear the maximum pressure, safety valves shall be installed at the discharge of the machines.
E. Pressure vessel for combustible gas or combustible liquid, which may likely be over-pressured than the design pressure if the medium expands due to being heated.
4.4.2 The open pressure (set pressure) of safety valve shall not be more than the design pressure of pressure vessels.4.4.3 Safety valve should not be installed on the following process equipment:A. Heating tube of furnaces or ovens ;
B. Equipment belonging to one common pressure system which has safety valve at the pressure source, safety valve can be omitted. But the purging steam should not be considered as pressure source.
4.4.4 The outlet connection of safety valve for Class A, B, C equipment shall be in compliance with following specification:A. The exhaust pipe of safety valve for combustible liquid equipment shall be connected to storage tank or other container; the exhaust pipe of safety valve for pump should be connected to the suction line of the pump, column or other conta, iners.
B. The exhaust pipe of safety valves for combustible gas shall be connected to flare system or other safety relief facilities.
C. The combustible gas or combustible liquid, which may likely burn instantly after relieving shall be cooled prior to be connected to the vent system
D. The combustible gas which may likely entrain corrosive drops shall be connected to flare system after being separated.
4.4.5 For safety valve which may be plugged or corroded by medium, prior to the inlet of safety valve, rupture discs shall be installed or clog-proofing measures such as purging, heating or insulating shall be taken.4.4.6 For Class A, B, C equipment, emergence discharge facilities shall be considered and following specification shall be met:A. For equipment storing liquefied hydro-carbon or combustible liquid, the material inside the equipment shall be possible to be pumped to storage tank, the residue shall be drained to flare system.
B. For equipment storing combustible gas, the gas shall be possible to emitted to flare system or safety vent system.
4.4.7 For heating furnace of coking unit, the cooling facility for emergency discharge of combustible liquid shall be installed inside furnace.4.4.8 For atmospheric vacuum distillation unit, the incondensible gas from the overhead of primary distillation column of atmospheric pressure or vacuum distillation column shall not be vented to the atmosphere directly.4.4.9 The height of combustible gas exhaust duct or vent pipe shall be in accordance following specification:A.
For continuous emission of combustible gas, the outlet of exhaust duct or vent-pipe shall be 3.5m above the building and platforms in the range with the radius 20m; for the platforms or buildings out side of the range, the arrangement shall be in accordance with the specification in Fig. 4.4.9, B. For intermittent emission of combustible gas, the outlet of exhaust duct or vent-pipe shall be 3.5m above the buildings and plateforms in the range of the radius 10m; for the buildings and plateforms outside the range, the arrangement shall be in compliance with the specification in Fig. 4.4.9.
4.4.10 For reaction equipment involving hazardous material which may likely be over-pressured suddenly or instant decomposition and explosion may take place, if installing safety valve cannot satisfy requirements, rupture disc or rupture with explosion pilot-pipe shall be installed, the pipe outlet must be oriented towards safe locations with no fire source; if required, proofing measures for secondary explosion and fire shall be taken.4.4.11 For reaction equipment involving material which may likely result in fire and explosion disaster due to over-temperature and over-pressure caused by sudden polymerization and sudden decomposition reaction, alarming device and pressure relief and discharge device shall be installed, as well as automatically and manually remote-control devices shall be installed also for emergenc shut-down of material adding.4.4.12 It is forbidden to mix and vent for gases which may possibly take place chemical reaction and form explosive mixture after being mixed.4.4.13 The installation of flare inside plant shall meet following requirements:A. The combustible gas emitted into the flare must not entrain combustible liquid;
B. For the determination of flare height, the heat radiation shall not be enough to affect the safety of personnel and equipment.
C. On the top of flare, perpetual lamp and other reliable igniting device shall be installed.
D. In the range of the 30m radius, combustible gas must not be vented.
4.5 Fire-resistance Protection4.5.1 For following load-bearing steel structure, supports, skirts, pipe supports, fire-resistance cover shall be made.A. Load-bearing steel structure, steel supports, steel skirts for Class A, B, liquid equipment with unit volume at or above 5m3;
B. Load-bearing steel structures, steel supports, steel skirts for combustible liquid equipment with unit volume at or above 5m3, in which the temperature is equal to or more than its ignition point;
C. Steel support for furnace;
D. Steel pipe-support for main pipe-rack located in explosion hazardous locations.
4.5.2 The range of fire resistance cover for load-bearing steel structure support, skirt and pipe-support shall be in accordance with following:A. Load-bearing steel structure: all of beams, columns under 4.5m for single-storey structures; all of beams, columns under 10m for multi-storey structures;
B. Load-bearing steel support for equipment and heating furnace: all of beams and columns;
C. Un-insulated section of exterior surface of steel skirts as well as the interior surface of steel skirts with the diameter more than 1.2m;
D. Steel pipe-rack: all of columns under 4.5m; in case the height of the bottom beam is over 4.5m, the cover may be made until 300mm from the beam bottom and should not be less than 4.5m; in case air-cooler placed on the pipe-rack, the brace of pipe-rack shall be covered with fire-resistance layer.
4.5.3 The duration of fire-resistance cover shall not be less than 1.5h;4.6 Others4.6.1 The design of heating, ventilation and air-conditioning for close factory house involving Class A, Class B equipment and explosion-hazardous dust, combustible fibre shall be in accordance with relevant specification of current state standard “Code for Design of Building Fire Protection” and Code for Design of Heating, Ventilation and Air-conditioning”.4.6.2 For the locations setting-off explosion hazardous dust or combustible fibre, the classification of fire-hazardous and explosion-hazardous location shall be in accordance with current state standard “Code for Design of Building Fire Protection” and “Code for Design of Electrical Installation in Explosion-hazardous and Fire-hazardous Locations”.4.6.3 For locations setting off explosion-hazardous dust or combustible fibre, measures shall be taken to prevent dust and fibre from dispersing and flying.4.6.4 For factory house setting off heavier-than-air Class A gas, explosion-hazardous dust or combustible fiber, non-sparkle generating pavement shall be adopted; the interior surface shall be smooth and glossy.4.6.5 For multi-story buildings involving combustible liquid measures shall be taken to prevent the combustible liquid from seeping to the lower story.4.6.6 In case producing or storing unstable olifenic hydrocarbon, diolifene, etc., measures shall be taken to prevent from generating super-oxide and auto-polyme.4.6.7 Class A, BI equipment and pipelines shall be furnished with inert-gas replacement device.4.6.8 On the suction line of combustible gas compressor, measures shall be taken to prevent from generating vacuum pressure.4.6.9 In case self-transferance have to be applied for the rotating equipment inside the explosion-hazardous locations, anti-static measures shall be adopted.4.6.10 In case air possibly exist in combustible liquid container, the inlet shall be connected from the bottom of the container; if having to be from the top of the container, the pipe shall be extended 200mm from the container bottom.4.6.11 In case a plant involving Class A, BI combustible liquid, the principle of combining regional monitoring and control of major locations should be adopted by installing combustible gas alarms and detectors.4.6.12 For fuel gas heating furnace perpetual lamp shall be installed, and flame monitor should be installed also.4.6.13 Any heat-insulated lining equipment (excluding heating furnace), the outside shell shall be painted with temperature indicating paint or be furnished with temperature detector.4.6.14 In side a plant setting off heavier-than-air Class A gas, the power cable shall be installed overhead and the cover should be of fire-retarding material.4.6.15 For the cable trench in plant, measures shall be taken to prevent combustible gas from accumulating or prevent combustible waste-water from entering-trenches. The power cable trench passing into substation central-control room, the opening on the wall shall be sealed and blocked completely.4.6.16 The electric-filtrating system for combustible gas, such as electric deducting, smog removing, device shall be installed to prevent from generating vacuum and to prevent oxygen content from exceeding the limit.4.6.17 The suction location of forced ventilation should be located at the down-wind of Class A, BI equipment where there is the least frequency wind direction in whole gear. The height of the location shall be selected from the bigger one of the following two cases: 9m above ground or 1.5m above explosion-hazard locations.5 Storing and Transporting Facilities5.1 General5.1.1 The tank foundation, fire embankment and partition wall for liquefied hydro-carbon, combustible liquid and combustible gas, as well as jetty, pipe-rack, and slipper etc. for combustible liquid and fire supporting gas shall be of non- combustible material.5.1.2 The insulation layer of liquefied hydro-carbon, combustible liquid shall be of non-combustible material. In case applying fire-retarding foam plastics, the oxygen index shall not be less than 30.5.1.3 In side the tank group of combustible gas, fire-supporting gas, liquefied hydro-carbon and combustible liquid, irrelevant pipelines shall not be installed.5.1.4 Where liquefied hydro-carbon may leaks out, combustible gas alarming detector should be installed.5.2 Above Ground Tank of Combustible Liquid5.2.1 The storage tank shall be of steel material.5.2.2 For storing Class AII CI combustible liquid, floating roof or floating-cabinet type inner floating-roof tank (herein after refer to as inner floating-roof tank) should be applied, a shallow disc type inner floating-roof tank shall not be applied.Pressure storage tank shall be adopted for storing Class AII liquid whose boiling point is below 45℃.
5.2.3 Apart from crude oil tank with insulation layer, Class AII liquid fixed-roof tank or pressure tank shall be furnished with fixed type, anti-sun light cooling-water-spraying system or other facilities.5.2.4 Storage tanks shall be arranged in groups and following specifications shall be met:A. In a tank group, the same and similar class of fire-hazard tank should be placed together;
B. Boiling-spill liquid tank shall not be arranged in the same group with non-boiling-spill liquid tank;
C. Liquefied hydro-carbon storage tank shall not be arranged in the same group with combustible liquid.
5.2.5 The total volume of liquid tank group shall be in accordance with following specification:A. The total volume of fixed-roof tank group shall not be over 120,000m3 ;
B. The total volume of floating-roof tank group and inner floating-roof tank group shall not be over 200,000m3 .
5.2.6 The quantity of tanks in a group shall not be more than twelve; but for tanks with each volume less than 1000m3 and Class CII liquid tanks, the specification is in-valid.5.2.7 The fire-distance of adjacent above-ground combustible liquid tanks in a tank group shall not be less than the specification in Table 5.2.7.Table 5.2.7 Fire-distance of Adjacent Above-ground Combustible Liquid Tank in tank group
Note:
(1) The figure D in the table refers to the bigger one of two adjacent tanks;
(2) The fire-distance of adjacent tanks which stores different class combustible liquid or different type, the bigger one of the values shall be adopted;
(3) Fire distance of elevated tanks shall not be less than 0.6m;
(4) For the shallow-disc floating-roof tank, the fire-distance is the same as for fixed-roof tank
5.2.8 The number of tank rows in a tank group shall not be more than two; but for the Class CII storage tank with unit volume less than or equal to 1000m3, the number of tank rows shall not be more than four; in which there is no specification for unit volume and row number for lube-oil tanks.5.2.9 The distance of two rows of vertical storage tanks shall be in accordance with the specification in Table 5.2.7 and shall not be less than 5m; and it shall not be less than 3m for two rows of horizontal storage tanks.5.2.10 Fire-dike shall be installed for tank groups; but for ones located in hilly region, the topography can be made use of to serve as emergence liquid basin, instead of fire-dike.5.2.11 The effective volume inside dike shall be in compliance with following specifications:A. For fixed-roof tank, it shall not be less than the volume of the largest one in the tank group;
B. For floating-roof tank, inner-floating-roof tank, it shall not be less than half of the volume of the largest one in the group;
C. In case the fixed-roof tanks are arranged in the same group with floating-roof tank, inner-floating-roof tank, the bigger one of above two Clauses shall be selected.
5.2.12 The distance from vertical tank to the foot of fire-embankment shall not be less than the half of the height of the tank shell; for horizontal tank, the distance to the foot shall not be less than 3m.5.2.13 Fire space not less than 7m wide shall be reserved between the exterior foots of two adjacent tank group fire-dike. For tank group furnished with emergence liquid basin, the distance for tank or tank group to the adjacent tank shall not be less than 25m, and not less than 7m fire space shall be reserved in-between.5.2.14 Inside tank group furnished fire-dike, the partition dike shall be installed in accordance with the following requirements:A. In case the unit volume is less than or equal to 5000m3, the sum of tank volumes inside the partition walls shall not be more than 20,000m3 ;
B. In case the unit volume is above 5000m3 to less than 20,000m3, partition dike can be made every four tanks;
C. In case the unit volume is above 20,000m3 to 50,000m3, partition dike can be made every two tanks;
D. In case the unit volume is above 50,000m3, tanks shall be partitioned every one;
E. The quantity of tanks in partition dike for boiling-spill liquid shall not be more than two.
5.2.15 In a tank group of various class combustible liquid, partition dike shall be installed in accordance with following requirements:A. Between Class AII, CI combustible liquid tank and other combustible liquid tank;
B. Between aqueous combustible liquid and non-aqueous combustible liquid tanks;
C. Between tanks for combustible liquid which can result in chemical reaction due to mutual contact;
D. Between combustible promoter strong oxidant and corrosive liquid tank and combustible liquid tank.
5.2.16 For the design of fire-dike and partition-dike, following specification shall be met:A. Fire dike and partition dike shall be possible to bear the hydraulic pressure of the liquid, and shall not leak out;
B. For vertical storage tank, the height of fire-dike shall be equal to the calculation result plus 0.2m, and should not be lower than 1.0m; for horizontal storage tank, the height of fire dike shall not be lower than 0.5m;
C. The height of partition dike shall be 0.2~0.3m lower than fire-dike at the point passing through dike for pipeline shall be closely sealed by use of non-combustible material;
D. In side the fire dike, measures shall be taken at the point passing through dike for rain ditch to prevent combustible liquid from flowing out of the dike;
E. On different orientation of fire dike, more than two stages or ramps shall be installed; stages shall be installed for all of partition dike;
5.2.17 The installation of emergence basin shall be in compliance with following specification:A. Around tank group furnished with emergence basin, drain ditch shall be installed to enable spilled-liquid smoothly flow out of tank group and gravity flow to the basin;
B. The distance from emergence basin to storage tank shall not be less than 30 m;
C. The distance from emergence basin, drain ditch to direct-firing location shall not be less than 30 m;
D. Emergence basin shall be furnished with water drainage facilities;
E. The volume of emergence basin shall be in compliance with Clause 5.2.11;
5.2.18 Fixed-roof tank of Class AI. C. liquid shall be furnished with fire arrestor and breath valve.5.2.19 For fixed-roof tank, weak-roof architecture shall be adopted for the connection between the roof plate and edge angle steel.5.2.20 For Class CII liquid storage tank with temperature above 100℃, special purge line shall be installed.5.2.21 For storage tank with steam-heater, the anti-over-temperature measures shall be adopted.5.2.22 For combustible liquid tank, level gauge and high-level alarm shall be installed; if required, shut-down device for liquid-adding by auto-interlock may be installed.5.2.23 Material adding pipe-line shall be connected to the lower part of storage tank; if required to be connected to the upper part, the connection tube shall extend to the tank bottom with a clearance of 200mm.5.2.24 In case there is possibility for tank foundation to settle continuously during operation, metal hose connection and other flexible joint shall be adopted on inlet and outlet nozzle.5.3 Above-ground Liquefied Hydro-carbon, Combustible Gas and Combustion-supporting Gas Storage Tank..5.3.1 Hydro-carbon storage tank, combustible gas tank shall be arranged in groups respectively.5.3.2 In case liquefied hydro-carbon tank are arranged in groups, following requirements shall be met.A. the number of rows in group shall not exceed two; in case there is no loop fire-vehicle access, tanks shall be arranged in single row.
B. there is no restriction on the total volume of a group, but the quantity of tanks in a group shall not exceed 12;
C. in case the total volume of a tank group exceeds 6000 m3 , partition dike shall be installed. The volume of partition dike shall not be more than 6000 m3 ; in case unit volume of tank is at or above 5000 m3, tanks shall be partitioned every one.
5.3.3 In side the tank groups of liquefied hydro-carbon, combustible gas combustion-supporting gas, the fire-distance shall not be less than the specification in Table 5.3.3.Table 5.3.3 Fire-distance of tank in groups for liquefied hydro-carbon combustible gas, combustion-supporting gas
Note:
(1) D is the diameter of the bigger one of two adjacent tanks;
(2) for the fire-distance of different type storage-tanks, the bigger value shall be adopted
(3) for fire-distance for liquid ammonia and liquid oxygen, refer to liquefied hydro-carbon storage-tank.
5.3.4 The distance for two rows of horizontal tanks shall not be less than 3 m;5.3.5 The distance of tanks in adjacent liquefied hydro-carbon tank groups shall not be less than 16 m;5.3.6 For pressure storage tank of hydro-carbon, not more than 0.6m high fire-dike shall be installed; and the distance from the embankment to the storage tank shall be less than 3m; inside the dike cast-in-situ reinforced concrete pavement shall be adopted for the ground, and shall be ramped down towards the sides. The partition wall inside fire-dike should not be higher than 0.3 m.5.3.7 For cryogenic liquid ammonia storage tank, liquefied hydro-carbon storage-tank, fire-dike shall be installed; the effective volume inside the dike shall be equal to 60% of the volume of the largest one.5.3.8 The storage efficiency factor for liquefied hydro-carbon tank liquid ammonia tank etc, shall not be more than 0.9.5.3.9 The load bearing steel support-legs for liquefied hydro-carbon storage tank shall be covered with fire-resistance layer; the duration of fire resistance shall not be less than 1.5h.5.3.10 For liquid ammonia storage tank, level gauge, pressure gauge and safety valve shall be installed; for cryogenic liquid ammonia tank, temperature indicater shall be installed also.5.3.11 On liquefied hydro-carbon storage tank, liquid level gauge, temperature gauge, pressure gauge, safety valve, as well as high-level alarming device or high level auto-down device for material adding by inter-dock shall be installed.5.3.12 Water-trough type storage tank for combustible gas, combustion-supporting gas, high/low level limit alarm shall be installed; and automatic inter-lock shut-down device shall be installed on in-coming line and out-going line.5.3.13 The exhaust pipe of safety valve for liquefied hydro-carbon storage tank shall be connected to the flare system. In case there is difficulty indeed, it can be vented locally, but the outlet of exhaust pipe shall be 3m higher than the platform of the highest adjacent tank.5.3.14 For LPG storage tank, secondary dewatering system with antifreeze measures shall be taken.5.3.15 At the gaseous phase part inside LPG evaporator, the pressure indication instrucments and safety valve shall be installed.5.3.16 The gasket of flanges for opening nozzle on liquefied hydro-carbon tank, the seal of valve bonnet shall be of non-combustible material.5.4 Loading Facilities of Combustible Liquid, Liquefied Hydro-carbon5.4.1 For train loading facilities of combustible liquid, following specification shall be adhered to:A. Safety stages shall be installed on two ends of loading platform and about every 60m along the platform;
B. For Class AII, B, CI liquid, trench-channel type loading system must not be employed;
C. For Class AII, B, CI liquid, which is filled into tank-train with the top open, submersive loading-arm shall be applied;
D. The distance from loading pump-house to tank-train filling platform shall not be less than 8 m;
E. On the combustible liquid pipeline with 10m outside of the boundary of the loading platform, emergence cut-off valve which is convenient to operate shall be installed;
F. For Class CII liquid, the loading platform shall be furnished independently;
G. The distance from zero-level tank to the filling platform shall not be less than 6 m.
5.4.2 The fire-prevention design of tank-washing station shall be implemented in accordance with the relevant specification for combustible liquid loading facilities of the same class.5.4.3 The design of combustible liquid tank-truck filling station shall be in accordance with following specification:A. The entrance and exit of loading station shall be installed separately; in case the entrance and the exit share one gate, turn-round yard shall be furnished.
B. The pavement of the loading station shall be of cast-in-site concrete;
C. The interval of seats for truck loading-arm shall not be less than 4 m; and the distance between receiver tank and loading-arm seats shall not be less than 5 m;
D. The distance from loading-arm seat to pump for Class AII, BI liquid loading truck shall not be less than 8 m;
E. In case there is no receiver tank inside loading station, emergence cut-off valve which is convenient to operate, shall be installed on the filling pipeline with 10m away from the loading truck loading-arm;
F. For Class AII, BI liquid loading truck, submersive loading-arm shall be adopted.
5.4.4 The train and truck loading facilities for liquefied hydro-carbon shall be in accordance with following specification:A. Liquefied hydro-carbon train loading platform shall be installed independently;
B. Liquefied hydro-carbon must not be drained locally;
C. The distance among loading-arm seats for liquefied hydro-carbon loading truck shall not be less than 4 m;
D. The pavement inside loading station for liquefied hydro-carbon shall of cast-in-situ concrete;
E. In addition, the train loading facilities for liquefied hydro-carbon shall be in compliance with Clause 5.4.1 in the code;
5.4.5 The design of combustible liquid jetty, liquefied hydro-carbon jetty shall be in accordance with following specification:A. The minimum distance from jetty to the adjacent berth shall be in accordance to the specification in Table 5.4.5 based on the ship model:
Table 5.4.5 Minimum Distance of Adjacent Berthes for Jetty (m)
Note:
In case a ship anchored in the outer block of jetty，the specification is invalid.
B. Jetty for liquefied hydro-carbon shall be installed independently; in case not operated at the same time, it may share a jetty with other small-sized jetty for Class AII liquid;
C. The safety distance from jetty for liquefied liquid and liquefied hydro-carbon to other jetties, buildings and structures shall be in compliance with relevant specification in current state standard “Code for Design of Oil-loading Jetty Fire-prevention”;
D. Emergence cut-off valve convenient to operate shall be installed on the ship loading pipeline with 20m distance away from berthes or embankment;
E. Loading-arm or metal hose shall be adopted for loading pipe of liquefied hydro-carbon, and safety vent measures shall be taken.
5.5 Filling Station5.5.1 LPG filling station shall be in accordance with following specification:A. The filling room and cylinder warehouse for LPG should be open type or semi-open type buildings; for semi-open building, ventilation devices shall be installed on the lower part;
B. The residue of LPG shall be close drained and recycled, and must not be drained locally;
C. Filling station shall be furnished with solid enclosure-wall of non-combustible material with height not less than 2.5 m; for filling station inside plant, the lower part of enclosure wall shall be furnished with ventilation opening;
D. The pavement inside filling room and cylinder store room shall be of non-sparkle generating surface;
E. The distance from LPG receiver to filling room shall not be less than 10 m;
F. The in-doors pavement of filling room and cylinder storing room shall be more than 0.6m higher than the out-doors ground;
5.5.2 For hydrogen filling room, ventilation measures shall be taken on the ceiling;5.5.3 The filling room for liquid ammonia and liquid chlorine shall be open type building.5.5.4 Filled cylinder warehouse can be arranged in the same building with filling room, but partition wall should be installed in-between, and entrance/exit should be furnished for each.5.5.5 The full cylinder of LPG, liquid ammonia or liquid chlorine, and so on shall not be stored and piled in the open-air.5.6 Flare System5.6.1 Liquid, low-heat-value combustible gas, air, inert-gas, acidic gas and other corrosive gas shall not be emitted to flare system.5.6.2 Combustible gas vent line shall be furnished with separators, arrestors and ect., before entering to flare system.5.6.3 The condensate in combustible gas vent pipe shall be closely recycled, and it is forbidden to discharged carelessly.5.6.4 Flare shall be furnished with reliable igniting system.5.7 Pump and Compressor5.7.1 The arrangement of combustible gas compressor and the design of its house shall be in compliance with the specification of Clause 4.2.24.5.7.2 The arrangement of combustible liquid and the design of its house shall be in compliance with the specification of Clause of 4.2.25. In case the quantity of liquefied hydro-carbon pumps is not more than two, it can be arranged in the same house with combustible liquid pump.5.7.3 For combustible gas compressor house, liquefied hydro-carbon pump house or combustible liquid pump house, the installation of emergency exit shall be implemented in compliance with Clause 4.2.31 in this code.5.7.4 In case Class A, BI liquid pump house, combustible gas compressor house are arranged adjacently to transformer and distribution substation or control room, the doors and windows of substation and control rooms shall be located outside explosion hazardous area.5.7.5 The discharge lines of electric reciprocating pump, gear pump or screw pump shall be furnished with safety valve; the exhaust pipe of the safety valve shall be connected to the suction lines of the pump, and emergence inter-lock shut-down device should be installed.5.7.6 On the discharge of each stage for reciprocating combustible gas compressor, safety valve shall be installed; the exhaust pipe line of safety valve shall be connected to the suction line of the first stage.5.8 Process Line and Steam Line5.8.1 The process line and steam line for whole plant shall be routed above ground.5.8.2 On the segment of process line passing over railway and road, valves and bellow expansion joints or slip-on expansion joints shall not be placed, and it shall not be connected by flange or thread.5.8.3 The piping arrangement on multi-story pipe-rack shall be in accordance with Clause 4.3.5 of this code.5.8.4 The connection of process lines shall be in compliance with following specification:A. Unless required to be flanged and threaded, the connection for valves and equipment nozzles shall be welded;
B. The lines conveying high-viscosity medium and condense-susceptible medium shall be connected by flange.
5.8.5 Between a couple of stop valves on uninsulated, un-drained, above-ground pipelines conveying Class A, B liquid, pressure relief measures shall be taken.5.8.6 The piping arrangement among tank groups shall not affect the passage for fire-vehicles.5.9 Warehouse in Plant5.9.1 The warehouse for Class A, B and C goods shall be in compliance with following specifications:A. The storage of stored Class A goods shall not exceed 30 t; in case the storage is less than 3 t, the warehouse for Class A goods can share one building with those for Class B, C goods; however the warehouse for Class A goods shall be partitioned from those for Class B, C by use of solid wall, and the entrance and exit shall be installed individually.
B. The storage for Class B, C goods should not exceed 500 t;
C. Goods shall be stored separately in accordance with the physical property and chemical property; in case it is not allowed to be stored together for property reason, solid wall shall be adopted for partition and entrance and exit be installed individually.
D. The ware-house shall be ventilated properly;
E. The pavement inside the warehouse shall be non-sparkle-generating surface and shall be furnished with water-proofing layer.
5.9.2 For synthetic fibber, artificial rubber, synthetic esters, plastics, urea and so on, the fire-resistance degree of ware-house shall not be lower than Grade II; the occupancy area of unit room is not specified.5.9.3 For the elevated warehouse for synthetic fibber, artificial rubber, synthetic esters, plastics and other packed goods, following specifications shall be met:A. The fire-resistance degree should not be lower than Grade II;
B. The shelf shall be of non-combustible material;
C. Fire alarm and fixed water showering (spraying) system should be installed.
5.9.4 The warehouse for what can form explosive mixture of dust and fibber in the air shall be ventilated properly; fire-alarming and fire-extinguishing system should be installed5.9.5 For bagged ammonium-nitrite warehouse, the fire-resistance degree shall not be lower than Grade II. Inside the warehouse, other goods are forbidden to store.5.9.6 In case light container (eg., cylinders, drums) are stored outdoors, anti-sunlight (shelter or water showering (spraying ) facilities shall be furnished.5.9.7 The storage of carbon di-sulfide shall be in compliance with following specifications:A. The indoor temperature of the ware-house should be kept in the range of 5~20℃；
B. Empty drums and filled drums shall not be stored in the open-air;
C. Filled drums shall be placed vertically by single story;
D. The lower part of the warehouse for drummed carbon-di-sulfide shall be ventilated properly;
E. In case the heating medium for the warehouse is over 100 ℃, insulation measures shall be taken on heating tube and heating radiator;
F. The storage tank shall not be placed in the open air; hydraulic seal shall be installed inside the tank, which shall be protected by anti-frozen measures.
6 Combustible Liquid Containing Process Waste-water Pipeline, Waste-water Treatment Unit and Circulating Water Station6.1 Combustible Liquid Containing Process Waste-water Pipeline6.1.1 Combustible liquid containing process waste-water and rain-water seriously polluted by combustible liquid shall be drained to process waste-water conduit. But for the condensate of combustible gas and following stated water shall not be discharged directly to the process waste water system:A. Water: the temperature will exceed 40℃ after merged with the waste-water on the discharge point;
B. Waste water: the chemical reaction will lead to fire disaster and explosion accident during mixing;
6.1.2 For the process waste-water pipeline, covered conduit or covered gutter with the thickness of covering soil not-less-than 200mm shall adopted. In case open ditch has to be adopted to drain inside plant, hydraulic seals shall be furnished to divide the open ditch into several segments, and the length of each segment should not exceed 20 m6.1.3 Plant production waste-water header line shall not pass through process plants, tank groups and other facilities or residential zone.6.1.4 For production waste-water pipeline, following parts shall be furnished with hydraulic seals; and the hydraulic height of seals shall not be less than 250 mm:A. At the drainage point of the dikes for columns, furnaces, pumps and cold-exchangers inside plants;
B. At the drainage point of process units, tank groups or other facilities, and buildings, structures, piping ditches and so on;
C. On the sub-header at the tie-in point where the sub-header intersects with main header;
D. The plant header, sub-header shall be partitioned by hydraulic seal in case the length of the header exceeds 300 m.
6.1.5 For gravity flow return line of circulating water, hydraulic seal pots shall be installed on the general discharge point for a plant, and the hydraulic water head shall not be less than 250 mm.6.1.6 In case one building is divided into several rooms by fire wall, each production waste water pipeline from individual room shall be furnished with independent egress and hydraulic seal.6.1.7 The production waste water line inside tank groups shall be furnished with independent discharges and hydraulic seal outside fire dike.6.1.8 For production waste water pipeline inside Class A, B process plants, vent pipe shall be installed in the following positions:A. At the hydraulic seal of header and the highest check well;
B. At the hydraulic seal leaving out of plants.
6.1.9 The installation of vent pipe shall be in accordance with , following specifications:A. The size of vent pipes should not be less than 100 mm;
B. The outlet of vent pipe shall be 2.5m above ground, and 2.5m above the operating platform, air cooler in the range of 3m away from the vent pipe;
C. In the range of radius 15m from direct-firing location and sparkle-generating location, vent pipe shall not be installed.
6.1.10 For production waste water conduit inside Class A, B process plants, the gap between the well covers and the seats shall be closely sealed; and the opening on the cover is not permitted.6.1.11 For production waste water system inside process plants, the combustible-liquid separation tank shall be furnished with covers of non-combustible material.6.2 Waste-water Treatment Unit and Circulating Water Station6.2.1 The protection height of oil-separation basin shall not be less than 400 mm.And oil-separation basin shall be furnished with non-combustible covers, and also with steam smothering system.
6.2.2 The incoming and outgoing lines of oil-separation basin shall be furnished with hydraulic seal pots. For hydraulic seal well, check well within 5m away from oil-separation basin, the gap between the covers and the seats shall be hydraulically sealed, and the openings on the cover is not permitted.6.2.3 The fire-distance for the arrangement of equipment, buildings and structures inside waste-water treatment units, shall not be less than the specification in Table 6.2.3.6.2.4 In case adopting poly-vinyl choride, fibber-glass reinforced plastics and others for the packing, water-collector of cooling tower, it shall be fire-retardant type and the oxidization index shall not be less than 30.Table 6.2.3 Fire Distance for Arrangement of Equipment, Buildings and Structures (m)
Note:
For other water sump with rarely much combustible liquid content, the fire-distance shall be the same as for oil-separation basin.
7 Fire-fighting7.1 General7.1.1 Petrochemical enterprise shall be furnished with suitable fire-fighting facilities corresponding to the material in progress of production, storage, transportation, which are provided to professional fire-brigade and operating personnel on duty.7.2 Fire-fighting Station7.2.1 Petro-chemical enterprise shall be furnished with fire-fighting station. The size of the station shall be determined considering the plant scale, characteristics of fire-hazard, concrete situations of furnishment of fixed fire-fighting facilities, as well as the cooperation conditions of adjacent stations, and other factors.7.2.2 The service coverage of fire-fighting station shall be calculated as mileage, which should not be more than 2.5 km; and the time for fire-vehicle to arrive fire accidental site should not be more than 5 min after receiving fire-alarm command.For particular locations of Class D, E, the service range can be enlarged to 4 km.
7.2.3 The position of fire-fighting shall be in compliance with following requirements:A. The station shall be convenient for fire-vehicle to pass through to process plants and tank farms;
B. The station should shun from plant main passage way;
C. The station should be far from noisy locations;
D. The station should be located in the down-wind of the production area where there is the least frequency of wind-direction in whole year.
7.2.4 The quantity of furnished fire-vehicles in a fire-fighting station shall be determined based on the conditions of fire-fighting system to meet the requirements to extinguish the biggest fire disaster.7.2.5 A fire-fighting station should be equipped with at least one set of big-sized dry-powder fire-engine, or dual-purposed one suitable for dry-powder and foam.7.2.6 A fire-fighting station must be equipped with device to receive fire-alarming signal and communication system.7.2.7 In case the storage of foam inside Grade I, Grade II fire-fighting station, suitable facilities should be installed to quickly fill foam into fire-engine.7.2.8 A central fire-fighting station shall be composed of garage, communication room, office room, duty-row dormitory, chemicals storage, storage facility, accumulator rooms, drying shed (in frigid region or rainy region), training classroom and training yard, training tower, as well as other necessary living facilities. The composition of fire-fighting substation should be determined based on concrete requirements.7.2.9 The fire-resistance degree of fire-engine garage shall not be lower than Grade II; the indoors temperature of the garage should not be lower than 12℃. Mechanical ventilation facilities should be installed in Grade I and Grade II garage.7.2.10 Garage and duty-rowing dormitory must be equipped with alarming bell, and on one side of the yard in front of garage, alarm lamp and alarm bell shall be installed to indicate maneuver of fire-engine. Emergence lighting system shall be installed on communication rooms, fire-engine garage, duty-row dormitory, and the corridors to the garage, etc..7.2.11 The garage gate shall be oriented towards road with a distance to the road edge not less than 15 m. Concrete or asphalt pavement shall be adopted for the front garage yard, with a slop not less than 2% towards the road.7.3 Fire-fighting Water Supply System(I) Fire-fighting Waster Supply Source
7.3.1 In case the fire-fighting water is supplied directly by process water supply source, the number of water-supply lines of a plant water net-work shall not be less than two. In case one line fails, the other may have the capacity to convey 100% fire-fighting water load plus 70% of the volume of process water and living water.In case the fire-fighting water is supplied by a fire water pond, the capacity of plant water-supply lines shall have the capacity to pass the make-up for fire-fighting water pond plus 100% of the sum of process water and living water.
7.3.2 For petrochemical enterprise, fire-fighting water basin shall be installed, which shall be in compliance with following specifications:A. The capacity of fire-fighting pond shall meet the demand for fire-fighting water consumption in the duration of fire accident. In case the make-up water can be supplied continuously in the event of fire accident, the capacity can be lessen by the make-up water in the duration of fire-accident.
B. In case the capacity of the fire-fighting water basin is less than or equal to 1000 m3, it cannot be partitioned; otherwise, it shall be partitioned into two with valved cross-over pipe.
C. The duration of water make-up for fire-fighting water basin shall not exceed 48 h;
D. In case the fire-fighting water pond is built-up together with other plant safety water basin such as living water basin or production water basin, suitable technological measures shall be taken for fire-fighting water pond and for avoiding being applied for other purpose.
E. In frigid region, anti-frozen measures shall be taken.
(II) Fire-fighting Water Consumption
7.3.3 The fire-fighting water consumption for plant area and residential area shall be determined based on the number of fire accidents occurred simultaneously and the corresponding fire-fighting water demand mean-time.7.3.4 The number of fire accidents occurred at-the-same-time in plant and residential area shall be determined in accordance with Table 7.3.4.Table 7.3.4 Quantity of Fire Accidents Occurred Simultaneously in Plant and Residential Area
7.3.5 For the branch-plant, tank farm and residential area, etc. in a complex enterprise, if there is independent fire-fighting water supply system for individual, the water demand shall be calculated respectively.7.3.6 The fire water demand for one-time fire-fighting shall be in compliance with following specification:A. Outdoors water supply of fire-fighting water for residential area and buildings shall be determined in accordance with the relevant specification stipulated in the current state standard “Code for Design of Building Fire Protection”;
B. Water supply of fire-fighting for process plant shall be determined comprehensively considering the plant scale, class of fire-hazard and the installation of fixed fire-fighting facilities, etc.. It can also decided in accordance with Table 7.3.6. The duration of water supply for fire-fighting should not be less than 3 h.
Table 7.3.6 Fire-fighting Water Demand for Process Plant (L/s)
Note:
Fire-fighting water demand for artificial fibre factory buildings may be determined in accordance with the relevant specifications of current state standard “Code for Design of Building Fire Prevention”.
C. Fire-fighting water demand for auxiliary production facilities may be calculated as 30 L/s. The duration of water supply for fire-fighting should not be less than 2 h.
7.3.7 Fire-fighting water demand for combustible liquid tank group shall be in compliance with following specifications:A. Fire-fighting water supply shall be calculated based on the tank group requiring the biggest of fire-fighting water demand, which shall be equal to the sum of water consumption for formulating foam and for cooling burning tanks and the adjacent tanks;
B. In case the number of adjacent vertical tanks exceeds three, tank cooling water consumption may be calculated as three tanks; in case the burning tank is floating roof or cabinet-floating type inner-floating-roof (excluding the floating roof is of fusible material), the water for cooling adjacent tanks may not be included.
C. In case the burning tank is vertical, the adjacent tank is referred to as the vertical above-ground tank in range of 1.5 times of burning tank diameter; in case the burning tank is horizontal, the adjacent is referred to as the above-ground tanks in the range of half of the sum of the length plus the diameter of the burning tank.
7.3.8 The supply range and intensity of fire-fighting cooling water for combustible liquid above-ground vertical tank shall not be less than the specification in Table 7.3.8.Table 7.3.8 Supply Range and Intensity of Fire-fighting Cooling Water
Note:
A. The water supply specifications for shallow-disc type inner floating-roof tank are calculated as for fixed-roof tank;
B. For storage tank with the tank wall higher than 17 m, mobile water-gun cooling should be adopted.
7.3.9 Mobile water-gun cooling system should be adopted for horizontal above-ground combustible-liquid tanks. The cooling area shall be calculated as the area of contour. Water-supply intensity: shall not be less than 6 L/min.m2 for burning tank; and not less than 3 L/min.m2 for adjacent tanks.7.3.10 Duration of water-supply for fire-fighting cooling for combustible-liquid tanks: shall be 6 h for fixed-roof tank with diameter over 20m and floating-cabinet type inner-floating-roof tank which the roof is of fusible material; and shall be 4 h for others.(III) Fire-fighting Water Supply Pipeline and Hydrants
7.3.11 Inside process area or tank farms, providing the technology and economy is rational, independent high-pressure fire-fighting water supply system shall be installed, whose pressure should be 0.7~1.2 MPa. For other locations, low-pressure fire-fighting water supply system, which share with the water supply system for production or living, shall be installed; the water-supply pressure shall ensure the water pressure at the worst position during fire-fighting not less than 0.15 MPa (calculated from the ground). Low-pressure water supply system shall not be shared with circulating cooling water system.7.3.12 The water supply network for fire-fighting shall be arranged in loop, and the arrangement shall be in compliance with following specifications:A. The number of the incoming lines for loop water supply network shall not be less than two;
B. The loop water supply network shall be divided into several independent piping sections, and the number of hydrants in each section should not be more than five;
C. In case a section fails, the other sections of the loop water supply network shall have the capacity to convey 100% of the fire-fighting water supply; for fire-fighting water supply pipeline, which combines with water supply system for production or livings, it shall have the capacity to convey 100% fire-fighting water supply plus 70% of the sum of the production water and living water;
D. Water supply for production and living shall be calculated as 70% of the flow per second on the basis of the peak hourly water consumption; and that for fire-fighting shall be calculated as the peak secondly flow.
7.3.13 Above-ground independent water-supply pipeline for fire-fighting shall be buried below frost level, and the distance from the level should not be less than 150 mm.7.3.14 The size of fire water-supply header for process plants or tank farms shall be determined by careful calculation, and should not be less than 200 mm.The velocity in independent water-supply pipeline should not exceeds 5 m/s.
7.3.15 The installation of hydrants shall be in accordance with following specification:A. Above-ground type hydrants should be selected preferably;
B. Hydrants should be lay down along road;
C. The distance for hydrants to road side shall not be more than 5 m; the distance to the exterior wall of buildings shall not be more than 5 m;
D. The distance for above-ground hydrants to urban road side shall not be less than 0.5 m; that to highway type double-lane road-shoulder shall not be less than 0.5 m; that to the centerline of single-lane road shall not be less than 3 m;
E. The big-sized outlet of above-ground hydrants shall oriented towards road;
F. Under-ground hydrant shall have noticeable indicator;
7.3.16 Quantity and arrangement of hydrants shall be determined by calculation based on the protection radius and the water consumption of protection subjects, and shall be in compliance with following specifications:A. The protection radius of hydrants shall not exceed 120 m;
B. The capacity of hydrants on high-pressure water supply pipeline shall be determined by calculation considering the pressure inside pipe and the required pressure at hydrant outlet; the capacity of NPS 100 mm, NPS 150mm hydrants on low-pressure water supply pipeline can be considered as 15 L/s, 30 L/s respectively;
C. For plants and tank farms, NPS 150mm hydrants should be installed.
7.3.17 For plant locations, the hydrants shall be arranged all around plant, and the interval should not exceed 60 m. In case the plant width exceed 120 m, additional hydrants should be installed along the road side in plant.The hydrants located in the range of 15m away from the tank-wall of combustible liquid tank farm, liquefied hydrogen tank farm, shall not be included in the quantity of applicable hydrants.
7.3.18 The hydrants on the fire-fighting water-supply pipelines which are shared for production and living, shall be furnished with isolating valves. In case it is allowed to stop water-supply during hydrant repairing, the isolating valves may not be installed.7.3.19 The fire-fighting water-supply pipeline and the hydrants inside buildings shall be determined comprehensively considering the characteristics of fire-hazard for buildings, property of material, building size and the situations of other fire-fighting devices.(IV) Box-type Hydrants, Fire Water-canon, Water Spraying and Water showering System
7.3.20 In the neighborhood of Class A gas compressors, furnace and other equipment requiring close protection inside plant, box-type hydrants should be installed, and the protection radius should be 30 m.7.3.21 For frame platforms higher than 15m, united column platform inside Class A, Class B process plants; in case there is no fire-fighting water canon to protect, vertical supply pipe for fire-fighting water should be installed along the ladders, which shall be in compliance with following specifications:A. Based on the requirements for each story, valved junction connection shall be installed;
B. For platform with the occupancy area less or equal to 50 m2, the size of water-supply pipeline should not be less than 80 mm; for platform larger than 50 m2, the size not be less than 100 mm;
C. In case the length of frame platform or united platform is more than 25 m, an additional fire-fighting water-supply vertical pipe should be installed along the ladders on the other side.
7.3.22 For Class A equipment 20m to 40m above ground in the boundary of plant, fire-fighting water canon should be installed on the both sides and there shall not exist obstructers for water spraying between the cannons and the protected equipment.7.3.23 For equipment more than 40m above ground inside the boundary of plant, which may likely result into explosion after heated, in case it cannot be protected by mobile fire-fighting equipment, fixed, semi-fixed and water-dripping or water spraying cooling system can be installed instead. The water spraying intensity should not be less than 8 L/min.m2, the area to be cooled shall be calculated as the surface area of equipment to be protected.7.3.24 For fixed fire-fighting devices in frigid region, such as box type hydrants, fire water canons, water showering or water spraying systems, anti-frozen measures shall be taken.(V) Fire-fighting Water Pump House
7.3.25 Fire-fighting water pump house shall be built with other pump house for living and production purpose; the fire-resistance degree of the building shall not be lower than Grade II.7.3.26 Fire-fighting water pump shall be furnished with self-filling withdrawal system。 In case the water level of fire-fighting water pond is at low level and self-filling withdrawal cannot be ensured, auxiliary suction system shall be installed.7.3.27 The suction pipe and discharge pipe of fire-fighting pump shall be in compliance with following specifications:A. Every fire-fighting water pump should be furnished with independent suction pipe; in case more than two pump are arranged in groups, the number of suction pipes shall not be less than two; when one pipe is on repairing, the other pipe shall ensure the pump to withdraw all of fire-fighting water;
B. For pump placed in groups, there shall be at least two discharge pipes connected with loop fire-fighting water network, and valves shall be installed between the two connections. In case one discharge pipe is on repairing, the other discharge pipes shall be possible to handle the whole fire-fighting water.
C. On pump discharge pipeline, anti-overpressure for safety devices shall be installed.
D. On pump discharge pipeline, the valves with NPS over 300mm should be electric-operated, hydraulic-operated or pneumatic-operated. And the valve shall have noticeable indicator for on-off position.
7.3.28 Fire-fighting water pump shall be furnished with standby pump. The capacity of standby pump shall not be less than that of the biggest fire-fighting water pump.7.3.29 Fire-fighting water pump should be possible to put into operation within 2 minutes after receiving alarm signal.7.3.30 Fire-fighting water pump shall be furnished with double power supply cables. In case adopting diesel generator as emergence stand-by power supply, the fuel storage for generator shall meet the requirements that the generating set run continuously for 6 h.7.4 Low-power Foam Extinguishing System7.4.1 For combustible liquid, low-power foam extinguishing system should be employed.7.4.2 For tank farms inside plant and some locations of big fire-hazard inside process plant, semi-fixed foam extinguishing system should be adopted.7.4.3 For remote independent tank farm far from plant, in case the topographical conditions is unfavorable or the volume of unit tank is so big that it is difficult for fire engine to put out fire, fixed foam extinguishing system should be adopted.7.4.4 To put out the fire due to combustible liquid leakage, oil tanks, vertical storage tank not-more-than 200 m3 and height of tank wall less than 7 m, or horizontal storage tank, mobile foam extinguishing system should be adopted. Mobile foam extinguishing system may also be applied as auxiliary system for fixed or semi-fixed foam extinguishing system for tank farm.7.4.5 The design of foam extinguishing system shall be implemented in accordance with relevant specification stipulated in the current state standard “Code for Design of Low-power Foam Extinguishing System”.7.5 Dry-powder Extinguishing System7.5.1 To put out the fire of combustible gas, combustible liquid, electrical equipment and metal alkyl oxide, etc., sodium-salt dry powder should be adopted. In case dry powder is utilized together with fluoro-protein foamite extinguishing system, sodium-silicide dry powder shall be chosen.7.5.2 Dry-powder extinguishing system should be adopted in the following locations:A. Fixed dry-powder extinguishing system should be adopted for close space, and shall ensure the volume of sprayed dry-powder to reach the design concentration of dry powder;
B. Semi-fixed dry-powder extinguishing system should be adopted for locations with relatively bigger fire-hazard;
C. Dry-powder fire vehicles should be adopted to put a fire of combustible gas in side of liquefied hydrocarbon tank farms and plants, leakage of liquefied hydrocarbon and combustible liquid.
7.6 Steam Smothering System7.6.1 Fixed or semi-fixed steam smothering system should be installed for process plant; But it shall not be installed on locations where the application of steam may likely lead to accident.7.6.2 Smothering steam line shall be connected from the top of steam header, and the steam pressure should not be more than 1 MPa.7.6.3 The nominal size of semi-fixed smothering steam quick-connection (herein after refer to as semi-fixed connection) shall be 20 mm; the length of fire-resisting hose should be 15~20 m.7.6.4 The arrangement of smothering steam pipeline shall be in compliance with following specifications:A. Inside a furnace chamber, a return-bend box conveying corrosive material or with plug furnished, fixed smothering steam perforated-tube (herein after refer to as fixed perforated-tube) shall be installed. The steam pipeline for each perforated-tube shall be connected from “Steam Manifold”. The distance for “Steam manifold”to furnace should not be less than 7.5 m; and at least two spare semi-fixed connections shall be reserved.
B. For in-doors less than 500 m2, closed-type Class A, B, C pump-house or Class A gas compressor-house, fixed perforated-tube shall be installed along one side wall of the house and at 150~200mm above ground; and adequate semi-fixed connections should be installed on the other side. For other Class A, B, C pump-house or combustible gas compressor house, semi-fixed connections shall be installed inside.
C. In the neighborhood of Class A, B, C equipment, semi-fixed connections should be installed; and in the neighborhood of combustible gas or combustible liquid equipment in which the operating temperature is at or above ignition point, semi-fixed connections shall be installed;
D. For Class A, B, C equipment multi-story frame or united platform for columns, semi-fixed connections should be installed on every story or every two stories.
E. If hose station is placed under the pipe-rack in process plant, in the neighborhood of Class A, B, C equipment located under pipe-rack or near pipe-rack, the semi-fixed connections may be omitted.
F. The valves for fixed perforated-tube or semi-fixed connections shall be placed on noticeable locations, which is safe and convenient to operate.
7.6.5 The steam supply intensity of fixed perforated-tube smothering system should be in compliance with following specifications:A. 0.003 kg/s.m3 for closed-type house or furnace chamber;
B. 0.0015 kg/s.m3 for return-bend box of furnace heating tube.
7.7 Installation of Extinguisher7.7.1 The extinguishers for production area should be dry-powder type or foam type, but for instrument room, control room, computer room, telecomunication station, laboratory room and so on, alkylogen type or carbon-dioxide type extinguishers should be installed.,7.7.2 The specifications of unit extinguisher installed in production area shall be selected from the models indicated in Table 7.7.2.Table 7.7.2 Specification of Extinguisher
7.7.3 The installation of portable dry-powder extinguisher for process plant shall be in compliance with following specifications:A. The maximum protection distance of extinguisher should not exceed 9m for Class A plant, and 12m for Class B, C plant;
B. The quantity of extinguishers installed in each position shall not be less than two, and extinguishers shall be installed for each story for multi-story frame.
C. For hazardous, important locations, wheeled extinguishers should be furnished in addition.
7.7.4 For train loading platform for combustible gas, liquefied hydrocarbon and combustible liquid, every 12m along the platform, one portable type extinguisher shall be installed above and under the platform respectively.7.7.5 For combustible gas, liquefied hydrocarbon and combustible liquid tank groups, one portable type extinguisher should be installed every 400 m2 occupancy area inside the fire dike; but the quantity of installed extinguishers for each tank should not exceed three.7.7.6 For extinguisher installation, unless specified in this chapter, the relevant specification in current state standard “Code of Extinguisher Installation for Buildings” shall be adhered to.7.8 Fire Alarming System7.8.1 Petrochemical enterprise must be furnished with fire alarming system. And fire-fighting station shall be equipped with proper instrument to receive fire alarm signal.7.8.2 Telephone fire alarming system shall be in compliance with following specifications:A. Grade I and Grad II fire-fighting station shall be furnished with alarm-receiving record telephones, which can handle fire alarm in case there are fires on not-less-than two locations at the same time.
B. Fire-fighting substation, production control center, fire-fighting pump house should be furnished with fire-alarm receiving and monitoring telephone.
7.8.3 Through dialing telephone shall be installed between fire-fighting station and fire-fighting pump house. Grade I and Grade II fire-fighting station should be furnished with wireless tele-communication devices additionally.7.9 Fire-fighting for Liquefied Hydrocarbon Tank Farm7.9.1 Liquefied hydrogen-carbon tank farm shall be furnished with fire cooling-water system, and mobile dry-powder extinguishers, etc..7.9.2 For liquefied hydrogen-carbon tanks over 100m3, fixed fire cooling water system and mobile water supply system for fire-fighting cooling shall be installed. In case the volume of tank is below or at 100 m3 or the tank is covered by hot-insulated layer, fixed fire cooling water system can be omitted. The mobile water supply system for fire cooling shall be capable to meet the total demand of cooling water for fire-fighting.7.9.3 The total demand of cooling water for fire-fighting for liquefied hydrocarbon tank farm shall be calculated as the sum of fixed fire-fighting cooling water plus mobile fire-fighting coo, ling water.In case no fixed fire cooling water system, the mobile water supply system for fire cooling shall be capable to meet the overall demand of cooling water for fire-fighting.
7.9.4 The demand calculation of cooling water for fixed fire cooling water system shall be in accordance with following specifications:A. Cooling water supply intensity for burning tank shall not be less than 9 L/min.m2;
B. For adjacent tanks in the range of 1.5 times the diameter of burning tank, the cooling water supply intensity shall not be less than 4.5 L/min.m2;
C. The cooling area for burning tank and adjacent tanks shall be calculated based on the tank surface;
7.9.5 The consumption of mobile fire cooling water shall be determined in accordance with the biggest one, and shall be in compliance with following specifications:A. The amount shall not be less than 30 L/s for tanks smaller than 400 m3, and 45 L/s for tanks bigger than or equal to 400 m3;
B. In case there is only one tank in tank farm, the calculation result can be reduced by half;
C. In case there is circulating water pond for fire engine to intake water, the amount of mobile fire cooling water may not be included into the total amount of fire cooling water.
7.9.6 The duration of fire water shall be calculated based on the required time for storage tank to vent in fire accident; in case the vent time exceeds 6 h, 6 hours shall be assumed.7.9.7 For fixed fire cooling water system, water spraying type, perforated tube showering type, or multi-tooth weir type, etc. may be adopted; in case the carbon deposits on the tank wall while the stored material is burning, water spraying cooling system shall be installed.7.9.8 In case fixed fire cooling water system is adopted for storage tank, auxiliary cooling water sprays should be installed for protecting the support-legs, valves, level indicators, safety valves and so on.7.9.9 The installation of fixed fire cooling water pipeline shall be in compliance with following specifications:A. For storage tanks over 400 m3, there should be two vertical supply pipes of fire-fighting water, which should be arranged symmetrically;
B. The control valves of fire cooling water system should be placed 15m away from the tank wall;
C. The pipe from the control valve to the storage tank shall be of galvanized pipe; whether to install strainers after control valve may be decided considering the characteristic of cooling water and the performance of spraying nozzle.
7.9.10 For mobile fire cooling water system, water gun or water canon may be adopted.In case adopting fixed fire water canon, the layout of water canon shall meet the requirements of service radius and operating distance.
7.9.11 The distance for fire cooling water circulating tank to the closest storage tank should not be less than 30 m, and devices should be installed to prevent floating debris and oils from entering the fire water pond.7.10 Fire-fighting for Oil Loading Jetty7.10.1 The fire-fighting facilities for oil loading jetty shall be capable to put out fires due to oil leakage in the loading area, or have the capability to extinguish the fires of the largest cabin of an anchored oil-ship in case it is in fires and there is no fire-fighting devices on it.The fire-fighting installation capacity of oil jetty shall be decided based on the bigger one of above stated two cases.
7.10.2 The fire-fighting capacity and facilities to put out fires due to oil leakage in the loading area shall be in compliance with following specifications:A. River type oil-jetty for 1000 t and more oil tanker to anchor or coastal type oil-jetty for 3000 t and more oil tanker to anchor, shall be furnished with fixed type or semi-fixed foam fire-fighting system;
B. River type oil-jetty for 5000 t and more oil-ship to anchor or coastal type oil-jetty for 10000 t and more oil-ship to anchor, should be furnished with not-less-than-two fixed tower type dual-purpose canons both for water and foam, whose protection radius is 40m and the ejecting intensity for combining solution should not less than 30 L/s.
C. Fire-fighting water supply: should not be less than 30 L/s for river type oil harbor and 45 L/s for coastal type oil harbor. The duration of firefighting water supply shall not be less than 2 h.
7.10.3 The fire-fighting capacity of facilities to put out fires for the largest oil cabin shall be in compliance with following specifications:A. The foam mixture supply intensity for fire-fighting shall not be less than 6 L/min.m2; and the protection area shall be calculated in accordance with the contour area of the largest oil-cabin;
B. The duration of foam mixture supply shall not be less than 30 min;
C. The fire cooling water supply intensity shall not be less than 3.4 L/min.m2; the protection area by cooling shall be calculated in accordance with the contour area of three cabins adjacent to the burning cabin;
D. The duration of fire cooling water supply: is 4 h when the area of burning oil-cabin is less than or equal to 300 m2, and 6 h when the area is more than 300 m2.
7.10.4 In case there is no fire-boat nearby to provide help, river type oil-jetty for 1000 t and more oil tanker, or coastal type oil-jetty for 3000 t and more oil tanker should be furnished with dual-purposed boat both for fire-fighting boat and tug-boat.8 Electric8.1 Power Supply and Power Distribution for Fire-prevention8.1.1 The power supply for fire-fighting electric equipment in fire water pump house in production area of petrochemical enterprise shall be in accordance with the requirements of Grade I power load stipulated in the current state standard “Code for Design of Industrial and Civil Electric Power Supply System”.8.1.2 Fire pump house and the accessoried power distribution room shall be furnished with emergency lighting; and accumulators may be adopted for standby power supply for emergency lighting; the duration shall not be less than 20 min.8.2 Lightning8.2.1 The classification of lightning and lightning installation for columns, buildings and structures in process plant shall be in accordance with the relevant specifications in current state standard “Code for Design of Building Lightning”.8.2.2 For columns, vessels and others placed in the open air in process plant, in case the thickness of roof is equal to or more than 4 mm, lightning arrestor may be omitted, but the grounding device for lightning must be installed.8.2.3 The steel storage tank for combustible gas, liquefied hydro-carbon, combustible liquid must be grounded for lightning, and in compliance with following specifications:A. The protection range of lightning rod (thread) shall cover the whole tank;
B. For fixed-roof above-ground tank with fire-arrestor installed for Class AII, B combustible liquid, in case the thickness of roof is at or above 4 mm, lightning rod (thread) can be omitted;
C. For Class C combustible liquid tank, lightning rod (thread) can be omitted; but grounding device of induction lightning must be installed;
D. For floating-roof storage tank, lightning rod (threa) can be omitted; but the floating roof shall be electrically connected to tank body by two copper cashes, whose section area shall not be less than 25 mm2;
E. For pressure storage tank, lightning rod (thread) may be omitted; but it shall be grounded for lightning.
8.2.4 For detecting devices for combustible liquid storage tanks, such as temperature gauges, level indicators, etc., armored cables or steel-tube cables shall be employed; the outside cover or steel tube for cables shall be electrically connected to the tank body.8.2.5 The requirements of electric-resistance for grounding shall be in accordance with the relevant specifications in the current state standard Code for Design of Petroleum Warehouse.8.3 Static Grounding8.3.1 For equipment and pipes which may likely produce static hazard in explosion hazardous locations or fire-hazardous locations, static grounding measures shall be taken.8.3.2 For pipeline conveying combustible gas, liquefied hydrocarbon, combustible liquid, combustible solid, static grounding device shall be installed at the following positions:A. At the incoming and outgoing points of plant or facilities;
B. At the boundary of explosion hazard area;
C. At in-line pump and its strainers, buffers, etc..
8.3.3 For combustible liquid, liquefied hydrocarbon, the metallurgic components of the loading platforms and jetties, pipelines, equipment, buildings, structures and steel rails of railway, etc. (excluding ones catholic protected) shall be electric connected and ground.8.3.4 Truck tank, train tank and the loading platform shall be grounded by special-use cable.8.3.5 The electric resistance for specially installed grounding device should be less than 100 W.8.3.6 Apart from the grounding device of independent lightning arrestor for Class I lightning system, the other grounding device may be applied for static grounding.
Appendix A Term ExplanationTable A.1
Appendix B Examples of Fire Hazard Classification of Combustible Gas
Table B.1
Appendix C
Examples of Fire Hazard Classification for Liquefied Hydrocarbon and Combustible Liquid
Table C.1
Appendix D
Examples of Fire Hazard Classification for Class A, B, C Combustible Solids
Table D.1
Appendix E
Examples of Fire Hazard Classification for Process Plant and Units
Table E.1
Section 1: Refinery Industry
Section 2: Petrochemical Industry
Section 3: Petrochemical Fibre Industry
Appendix F
Definition of Starting Point and Ending Point for Fire DistanceThe starting point and end point of fire distance for regional planning, plant general layout as well as arrangement in side plant and facilities are defined as below:
Equipment : Exterior edge of equipment;
Railway: Centerline of railway;
Road: &nbs, p; Road side;
Jetty: Center of oil loading-arm and berth;
Loading pick-pipe for train and truck: Centerline of pick-pipe;
Storage tank or tank group: Exterior wall of tank;
Flare: Centerline of flare stack;
Overhead telecommunication or power cable: Centerline of cable;
Process plant:
The exterior edge of the farest equipment or the farest axis of buildings and structures;
Appendix G Explanation of Wording in This Code
1. Words denoting the different degrees of strictness are explained as follows in order that they can be distinguished each other during the implementation of this code:
Words denoting a very strict or a mandatory requirement:
“must” is used for affirmation;
“must not” is used for negation;
Words denoting a strict requirement under normal conditions:
“shall” is used for affirmation;
“shall not” is used for negation;
Words denoting a permission of slight choice or an indication of the first choice when conditions allow:
“should ”or “may” is used for affirmation;
“should not” is used for negation;
“Be in accordance with”or “be in compliance with” are used in the text of this code for those items that names the related standards, codes or regulations as a must requirement to implement
Previous: Design for Low Expansion Foam Extinguishing System
Next: Fire Prevention Code of Petrochemical Enterprise Design [Amend 1999] |
||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
