GB/T 40113.1-2021Technical specification for the co-production engineering of biomass pyrolysis carbon gas oil—Part 1: Process design (English PDF)

6.2 Storage and transportation of biomass raw materials

6.2.1 The storage and transportation of raw materials include the collection, storage and transportation, screening, transportation, and impurity removal of biomass raw materials.

6.2.2 When raw materials are transported by vehicles, they should be unloaded directly in the raw material warehouse, and sufficient unloading space should be left in the raw material warehouse.

6.2.3 The storage capacity of raw materials should meet the production capacity of no less than 7 days, and the storage of raw materials should be rain-proof, moisture-proof, fire-proof and dust-proof.

6.2.4 The stacking and reclaiming operations in the raw material storage area can be carried out by wheel loaders or bridge grab cranes.

6.2.5 Light belt conveyors should be used for raw material transportation, the belt speed should not exceed 1.25m/s, and the designed delivery output of the belt conveyor should not be less than The subsequent biomass drying processing unit capacity is 1.2 times.

6.2.6 During the transportation of raw materials, no less than two-stage iron removal device should be installed.

6.3 Drying of biomass raw materials

6.3.1 A buffer silo should be set up in front of the drying furnace, and the design buffer time of the silo should not be less than 1.0h.

6.3.2 The feeding device in front of the drying furnace should have a metering function.

6.3.3 The design of the drying furnace should determine the reasonable drying flue gas temperature according to the type of raw materials, particle size, water content, ignition temperature and processing capacity And the residence time of the material.

6.3.4 The temperature of the flue gas at the outlet of the drying furnace should be more than 20°C higher than the dew point temperature.

6.3.5 The outlet of the drying furnace should be equipped with a first-level dust collector, and the pollutant discharge concentration after dust removal should meet the environmental protection requirements.

6.3.6 If a hot air furnace is used for auxiliary drying and heating in the process, the design heat load should take the maximum heat load required by the drying system, and the margin Not less than 10%; the outlet hot air temperature should be lower than the ignition point of the dried material.

6.4 Biomass pyrolysis

6.4.1 According to different pyrolysis processes, pyrolysis furnaces can use moving bed, fixed bed, fluidized bed and other furnace types, and continuous pyrolysis production should be preferred Craft.

6.4.2 The feed moisture of the pyrolysis furnace should be controlled below 15% (mass fraction).

6.4.3 The airtightness of the pyrolysis furnace should meet the process and safety requirements, and the necessary safety vents should be considered to prevent the equipment from overpressure.

6.4.4 The pyrolysis furnace should be equipped with necessary temperature and pressure online detection instruments to ensure that the pyrolysis temperature is adjustable and the product is controllable.

6.4.5 The design of the pyrolysis furnace shall fully consider the high temperature resistance and thermal expansion stress of the equipment materials.

6.4.6 The pyrolysis hot blast stove should be designed according to the dual-fuel system of burning biomass and self-produced gas.

6.4.7 The design heat load of the pyrolysis hot blast stove shall take the maximum heat load required by the pyrolysis system, and the margin shall not be less than 10%.

6.4.8 The low-temperature waste heat generated by the pyrolysis process can be used in the drying system to make full use of the heat.

6.4.9 The feed and discharge of the pyrolysis furnace should consider the patency of the material, and at the same time ensure the sealing of the pyrolysis furnace.

6.5 Purification of crude pyrolysis gas

6.5.1 Pyrolysis gas purification methods generally include wood vinegar liquid chilling, wood vinegar liquid washing and cooling, indirect heat exchange cooling of cooling water, filtration, acid-base neutralization, Adsorption and so on.

6.5.2 The pyrolysis gas contains dust, tar and other easily blocked components. It is advisable to use circulating wood vinegar to directly chill the pyrolysis gas to remove most of the dust and tar. tar.

6.5.3 The pyrolysis gas is circulated and washed with wood vinegar liquid and cooled continuously to further remove dust and tar.

6.5.4 The pyrolysis gas is cooled to normal temperature through indirect heat exchange of cooling water, so as to minimize the water brought into the subsequent system.

6.5.5 Pyrolysis gas purification system, the flow margin is not less than 10%, and the pressure head margin is not less than 15%.

6.5.6 The purification and treatment effect of pyrolysis gas should meet the subsequent use requirements.

6.6 Separation of tar/wood vinegar liquid

6.6.1 The tar and wood vinegar should be separated and meet the separate storage conditions.

6.6.2 To ensure the fluidity of tar, the temperature of tar should not be lower than 60°C.

6.6.3 Wood vinegar and tar products should be stored in atmospheric storage tanks, and the storage days should be considered comprehensively in conjunction with market and production and transportation conditions.

6.7 Storage of pyrolysis gas

6.7.1 The pyrolysis gas should be stored in a wet gas tank.

6.7.2 The design of the wet gas storage cabinet should meet the requirements of GB/T 51094 and GB 6222.

6.7.3 The gas storage tank should be equipped with a volume indicating scale and an automatic safety deflation device, which can automatically vent gas when the inflation exceeds the upper limit.

6.7.4 The inlet and outlet pipes of the gas storage cabinet shall be equipped with water sealing devices. A drain valve should be installed at the lowest point of the pipeline. The inlet and outlet pipes should be fixed on the pipe seat, To prevent the sinking of the foundation of the gas storage tank from causing pipeline deformation.

6.7.5 Flexible gas storage cabinets made of rubber or plastic should not be used.

6.7.6 The effective height of the liquid level of the water seal of the wet gas storage tank should not be less than 1.5 times the height of the liquid level at the maximum working pressure. Anti-freezing measures should be taken.

6.7.7 Appropriate internal and external anti-corrosion coatings should be selected for the gas storage cabinet according to its material, nature of fuel gas, and environmental conditions.

6.7.8 The semi-underground gas storage reinforced concrete sink, in addition to the design in accordance with GB 50010, should also be set at the bottom of the inlet and outlet valves. Water device.

6.7.9 The gas storage area includes gas storage tanks, control valves and other facilities. According to the gas demand of pyrolysis gas users, pyrolysis gas refueling can be set (or reserved). Pressure, gas mixing, pressure regulation, metering, odor addition and other facilities.

6.7.10 The design of the process facilities in the gas storage tank area should meet the requirements of GB 50028, and the design of the gas storage tank should meet the requirements of GB 50494.

6.8 Transportation of finished charcoal

6.8.1 The finished charcoal should be cooled by indirect heat exchange method. The cooled finished charcoal should be set up with a transitional storage area according to the cooling situation, and the temperature should not be higher than 40°C.

6.8.2 When calculating the area of the bagged finished charcoal warehouse, the area occupied by the stored materials should be 60% to 70% of the total area.

6.8.3 The quality of the finished charcoal should meet the requirements of relevant standards.

7.1 General provisions

7.1.1 The equipment and piping arrangement of the pyrolysis device should meet the requirements of the process flow, and should be in accordance with material pyrolysis, pyrolysis gas purification and liquid collection, etc. The process is arranged in sequence, and the height of the device and the floor area are reduced as much as possible, and the length of the pipeline is reduced, so as to be safe, reliable, economical and reasonable, neat and beautiful, and full Meet the requirements of construction, operation and maintenance.

7.1.2 The vertical arrangement of the equipment shall meet the following requirements.

a) The towers and containers that are pumped and transported by pumps or fans, as well as gravity flow, solid discharge and other equipment, should be arranged in accordance with the requirements of the process flow. Suitable floor;

b) Vibrating equipment should be arranged on the ground or lower floors, not on the steel structure floor.

7.1.3 The pyrolysis process equipment should be arranged in the open or semi-open (the pyrolysis project area should be open or semi-open), and the explosion hazard area should be reduced Range. The scope of the explosion hazard area should comply with the relevant regulations of GB 50058.

7.1.4 The pipelines with special requirements for distance, angle, height difference, etc., as well as the layout of high-temperature and large-diameter pipelines, should be arranged in the equipment. Plan as a whole.

7.1.5 The equipment in the device should take corresponding protective measures to meet the relevant requirements of fire prevention, explosion protection, corrosion protection, and antifreeze.

For equipment and pipes required for ironing, the temperature of the outer surface of the insulation layer should not be greater than 50°C.

7.1.6 According to the arrangement of equipment and pipelines, there should be sufficient space for installation and maintenance and transportation channels for maintenance. Appropriate lifting facilities.

7.1.7 Anti-corrosion measures should be taken for piping materials and fittings, and the design of other aspects should meet the requirements of GB 50316.

7.1.8 The welding construction of the pipeline should meet the requirements of GB 50236.

7.1.9 The pyrolysis gas pipeline design should meet the relevant requirements of GB 6222 for gas pipelines.

7.2 Equipment layout

7.2.1 In order to control the temperature drop of high-temperature smoke and meet the process requirements, the hot blast stove can be arranged close to its related process equipment, and the open flame should be facing away from the relevant For process equipment with combustible medium, the straight line distance between the open flame and the combustible medium equipment shall not be less than 15m.

7.2.2 The hot blast stove of the pyrolysis unit should be arranged under the lowest frequency wind direction of the device or equipment that may emit combustible gas. Wind side.

7.2.3 The centralized control room and the electronic equipment room can be arranged in conjunction with the pyrolysis device, and should meet the following requirements.

a) Auxiliary buildings such as centralized control rooms and electronic equipment rooms should be arranged outside the scope of the explosion hazard zone, and should be far away from vibration or noise Larger equipment should be near the edge of the device area;

b) The centralized control room and the electronic equipment room should be arranged on the high-temperature flue gas venting pipeline and the place where flammable and explosive gas may leak. Wind side;

c) There should not be any process pipeline passing through the centralized control room and the electronic equipment room.

7.2.4 The wood vinegar storage tank should be equipped with a cofferdam, and a corrosion-resistant ground should be laid in the cofferdam. The setting of the cofferdam should meet the following requirements.

a) The height of the cofferdam above the ground should not be less than 300mm;

b) Drainage ditches and water collection wells should be provided in the cofferdam, and valve wells outside the cofferdam to facilitate the collection of materials and the discharge of rainwater;

c) The ground in the cofferdam should slope towards the drainage ditch.

7.2.5 Because of the process requirements, blockage is likely to occur or the process requires the pipeline to be as short as possible, the upstream and downstream equipment should be arranged nearby.

7.3 Piping layout

7.3.1 The pipeline layout of the plant area should be laid overhead. If possible, it should be arranged in rows. The pipelines laid on the ground should be arranged in the pipeline. On corridors or pipe piers, the arrangement of pipes shall not hinder the installation and maintenance of equipment, pumps and their internal components.

7.3.2 The pipelines laid overhead throughout the plant shall not be arranged around process devices, system units or storage tanks, and shall not hinder the passage of fire trucks.

7.3.3 The tar pipeline decides whether to add heat tracing measures according to the ambient temperature, and should be provided with a slope, so that the pipeline layout and installation conditions are met.

The tar pipeline should be equipped with detachable flanges and other measures to prevent blockage.

7.3.4 The pyrolysis gas pipeline should not have liquid bags and should have a slope. The slope of the pyrolysis gas pipeline after purification should not be less than 0.003, and the remaining pyrolysis gas pipelines The slope is not less than 0.005.

7.3.5 The distance between the pyrolysis gas and high-temperature flue gas vent pipe port and the safety valve discharge port and the platform or building should meet the requirements in GB 6222 According to relevant regulations, all vents shall be treated as combustible gas.

7.3.6 The clear height and clear distance of pipelines, as well as the depth and spacing of buried pipelines shall meet the requirements of GB 50187.

8.1 Meter

8.1.1 General provisions

8.1.1.1 The design of measurement and instrumentation shall meet the requirements of safe and economic operation of the device, and be able to accurately measure and display the equipment of the process system The operating parameters and operating status of the system.

8.1.1.2 The control, detection, operation, alarm, data and event recording, data storage and other functions of the process shall be implemented in the control system.

The system should adopt centralized control. With the cooperation of a small number of on-site operations and inspection personnel, the operating personnel should pass through the operating station set in the control room. Realize the monitoring of the device.

8.1.2 Measurement and instrumentation

8.1.2.1 The instrument and control equipment should select the appropriate protection level according to the area.

8.1.2.2 According to the classification of hazardous locations, for instruments and control equipment installed in explosion-hazardous areas, appropriate explosion-proof instruments and controlling device.

8.1.2.3 The main parameters should be monitored. The measuring instrument should include the following.

a) Raw material moisture monitoring instrument;

b) The pressure remote measurement and recording of the gas storage device;

c) Display and record the operating status of each equipment and subsystem;

d) Overpressure and overtemperature alarm devices for various equipment;

e) pyrolysis gas temperature and pressure detection instrument;

f) Pyrolysis gas leakage alarm device;

g) Electricity, gas, water, raw materials, labor and management measuring instruments and meters for cost accounting.

8.2 Control system

8.2.1 The control system should adopt a distributed control system (DCS) or a programmable controller (PLC), and the control system should be equipped with an operating station, Chengshi station, printer, etc.

8.2.2 The key units and components of the control system shall adopt redundant configuration.

8.2.3 The load of the control system controller should not exceed 60%, and the number of various I/O channels should be reserved for 10% to 20% of the spare capacity, and the communication network The load should not exceed 40%.

8.2.4 The power supply of the control system should be UPS (uninterruptible power supply).

9.1 Electrical requirements

9.1.1 General provisions

9.1.1.1 The electrical design shall meet the requirements of the production process and the reliability of power supply and distribution, energy saving, consumption reduction, environmental protection, and personal and equipment safety.

9.1.1.2 Advanced energy-saving electrical products and complete sets of equipment shall be used in electrical design.

9.1.2 Power supply and distribution plan

The power supply and distribution plan should be based on the nature of the load, power consumption, project characteristics and local power supply conditions, etc., after a comprehensive technical and economic comparison determine.

9.1.3 Power supply and distribution system

9.1.3.1 Load classification and power supply requirements

The load classification and power supply requirements should meet the relevant regulations of GB 50052.

9.1.3.2 Power supply and power supply and distribution system, voltage selection and power quality, reactive power compensation

The power supply, the design of the power supply and distribution system, the selection of the power supply and distribution voltage, the power quality requirements and the reactive power compensation shall meet the requirements of GB 50052.