CN218435600U - Pure oxygen continuous gasification system - Google Patents
Pure oxygen continuous gasification system Download PDFInfo
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- CN218435600U CN218435600U CN202221951168.7U CN202221951168U CN218435600U CN 218435600 U CN218435600 U CN 218435600U CN 202221951168 U CN202221951168 U CN 202221951168U CN 218435600 U CN218435600 U CN 218435600U
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Abstract
The utility model discloses a continuous gasification system of pure oxygen, including the steam buffer tank, the entry of steam buffer tank has connect the low pressure steam pipe, steam pipe and gas mixing tank middle part access connection are passed through in the export of steam buffer tank, the bottom import of gas mixing tank has connect the gasification agent pipe, the exit linkage of gas mixing tank to the bottom import of pure oxygen stove, the top raw materials import of pure oxygen stove and the raw materials exit linkage of automatic coal charger, the upper portion water gas exit linkage of pure oxygen stove has the water gas pipe, water gas union coupling is to cyclone upper portion import, cyclone top exit linkage preheater, the top import of heat pipe waste heat boiler is connected at the preheater top, the bottom export of heat pipe waste heat boiler has connect the water seal groove through the pipeline, the water seal groove passes through the import of pipe connection system waste heat top, the bottom export of system waste heat recoverer passes through cooling tube connection coal gas cooler bottom import, the cooling tube is equipped with branch road intercommunication intercooling device, the upper portion export of coal gas cooler connects the coal gas house steward.
Description
Technical Field
The utility model relates to the technical field of raw material gasification in nitrogen fertilizer production, in particular to a pure oxygen continuous gasification system.
Background
With the continuous rising of coal price and the improvement of the environmental protection requirement of low-carbon life, in a raw material gas continuous gasification device in a synthetic ammonia production device, a fixed bed intermittent gas making process which is widely adopted at present is used for producing water gas for producing synthetic ammonia and methanol, which is determined by the structural characteristics of coal resources and the actual needs of the coal chemical industry in China. However, the technology of the intermittent gas making technology falls behind, the energy consumption of products is high, the production cost is high, more seriously, the discharge amount of three wastes is large, the investment of environment-friendly equipment and the operation cost are high, the production is seriously influenced, and the market competitiveness of enterprises is influenced. According to the actual production situation, the fixed bed intermittent gasification method only can use 30 to 80mm coal blocks as raw materials, the carbon conversion rate is about 60 percent, the coal gasification rate is about 75 percent, the raw material price is higher, the ash residue carbon is higher, the existing fixed bed intermittent furnace with the diameter of 2.8m is not recommended to use technology according to the requirements of relevant ministry of China, and in order to solve the problems, the continuous gasification system of the raw material gas in the existing synthetic ammonia production device needs to be improved.
Disclosure of Invention
The utility model discloses a solve present fixed bed intermittent type gas making technology production water gas, the technology falls behind, and the product energy consumption is high, and manufacturing cost is high, and the three wastes emission is big, and environmental protection equipment drops into and the running cost is higher, waits a series of outstanding problems and provides a pure oxygen continuous gasification system.
The utility model discloses a following technique realizes: the entry of steam buffer tank has connect the low pressure steam pipe, the export of steam buffer tank passes through steam pipe and gas mixing tank middle part access connection, the bottom import of gas mixing tank has connect the gasification agent pipe, the exit linkage of gas mixing tank's bottom import to the pure oxygen stove, the top raw materials import of pure oxygen stove and the raw materials exit linkage of automatic coal charger, the upper portion water gas exit linkage of pure oxygen stove has the water gas pipe, the water gas union coupling is to cyclone upper portion import, cyclone top exit linkage pre-heater, the top import of heat pipe waste heat boiler is connected at the pre-heater top, the bottom export of heat pipe waste heat boiler has connect the water seal groove through the pipeline, the water seal groove passes through pipe connection system waste heat recoverer top import, the bottom export of system waste heat recoverer passes through cooling tube connection gas cooler bottom import, the cooling tube is equipped with branch road intercommunication intercooling device, the upper portion export of gas cooler connects the house steward.
When the device is implemented, the inlet of the steam buffer tank is connected with a low-pressure steam pipe, the steam comes from an outer pipe network and self-generated steam, the outlet of the steam buffer tank is connected with the inlet in the middle of the gas mixing tank through the steam pipe, the inlet at the bottom of the gas mixing tank is connected with a gasifying agent pipe, the gasifying agent pipe is communicated with oxygen with the purity of 99.6% from an air separation device, the gasifying agent oxygen and the low-pressure steam are mixed in the gas mixing tank through metering and proportion adjustment, the outlet of the gas mixing tank is connected to the inlet at the bottom of a pure oxygen furnace, a special grate for the pure oxygen furnace is adopted in the pure oxygen furnace and is uniformly distributed through the grate, ash discharging devices without stopping the furnace are arranged on two sides of the furnace bottom, the top raw material inlet of the pure oxygen furnace is connected with the raw material outlet of the automatic coal feeder, small coke particles or small coal blocks as raw materials enter the automatic coal feeder from a coal bunker, the small coke particles or the small coal blocks are automatically added into the pure oxygen furnace in a timed and quantitative manner, a pressure charging and releasing device is arranged on the automatic coal feeder, mixed gas with the temperature controlled to 200 ℃ reacts with charcoal burnt in the furnace at high temperature to generate qualified water gas, the reaction is continuously carried out to continuously produce water gas, a jacket steam drum is arranged above the pure oxygen furnace, the jacket steam drum is connected with the pure oxygen furnace through an inlet and outlet pipeline, the jacket steam drum is connected with boiler deoxygenated water, and the jacket steam drum is connected to a steam buffer tank through a circulating pipeline; the upper water gas outlet of the pure oxygen furnace is connected with a water gas pipe, the temperature of the water gas generated by reaction ranges from 420 ℃ to 450 ℃, the water gas is discharged from the pure oxygen furnace, the water gas pipe is connected to the upper inlet of a cyclone dust collector for dust removal, an emptying valve is arranged at the top of the cyclone dust collector, the top outlet of the cyclone dust collector is connected with a preheater, the top of the preheater is connected with the top inlet of a heat pipe waste heat boiler, a heat pipe boiler steam drum is arranged above the heat pipe waste heat boiler, one side of the heat pipe boiler steam drum is connected to the heat pipe waste heat boiler through two inlet and outlet pipelines, the other side of the heat pipe boiler steam drum is connected to the preheater at the top of the cyclone dust collector through two inlet and outlet pipelines, the bottom outlet of the heat pipe waste heat boiler is connected with a water seal groove through a pipeline, the water seal groove is connected with the top inlet of the system waste heat recoverer through a cooling pipe, the bottom outlet of the system waste heat recoverer is connected with the bottom inlet of a coal gas cooler through a branch pipeline, and the upper outlet of the coal gas cooler is connected with a coal gas main pipe. When in use, the raw material small granular coke or small coal blocks enter the automatic coal feeder from the coal bunker, and are automatically added into the furnace through the raw material inlet at the top of the pure oxygen furnace in a timed and quantitative manner; gasifying agent oxygen for gas production enters a gas mixing tank from an air separation process through a gasifying agent pipe, steam comes from an outer pipe network and self-produced steam enters from an inlet at the upper part of the gas mixing tank through a low-pressure steam pipe, the mixed gas enters from an inlet at the bottom of a pure oxygen furnace at the temperature of 200 ℃, and is subjected to oxidation-reduction reaction with small coke or coal under the high-temperature condition in the furnace to continuously produce water gas; the water gas generated by the reaction is discharged from a water gas outlet at the upper part of the pure oxygen furnace through a water gas pipe, is dedusted by a cyclone deduster, enters a heat pipe waste heat boiler through a preheater from a top inlet, recovers the gas after the waste heat of the high-temperature gas, ensures the safety through a bottom water seal groove, enters a system waste heat recoverer from the top inlet, is discharged from a bottom outlet of the system waste heat recoverer at the temperature of about 150-170 ℃, enters an indirect cooling device, is cooled by a gas cooling device, and then enters a water gas main pipe.
Compared with the prior art the utility model discloses following beneficial effect has: the utility model provides a pure oxygen continuous gasification system, through air separator with purity for 99.6% oxygen extract with low pressure steam mix the back in mixing the gas pitcher, from the stove bottom entering gasifier with the charcoal of burning in the stove react under high temperature and generate qualified water gas and be used for synthetic ammonia device plant to use, utilize system's waste heat byproduct steam simultaneously. The pure oxygen is used for continuous gas making to perform energy-saving emission-reduction transformation, the existing intermittent gas furnace is replaced by the pure oxygen gas making furnace, the effective gas is improved, the exhaust emission is reduced, and the zero emission of three wastes is realized; the fixed carbon conversion rate is improved, the steam consumption is reduced, the production cost can be greatly reduced, the requirements of related national development policies are met, the capacity of the device is exerted, the long-term development of enterprises is facilitated, the overall configuration is reasonable, the sealing performance is good, the anti-flow measures are perfect, and the gasification strength is high.
The system can be additionally built or replaced in the original frame system, is not required to be completely replaced, can retain partial original equipment, fully utilizes the existing equipment to complete system replacement, is low in modification cost, short in construction period, low in construction difficulty, low in professional technical requirement and simple and convenient to operate, and can be used by post staff and workshop managers familiar with the environment, the process flow and the equipment running condition after modification in the operation process without excessive training.
After the project is finished, the project is put into operation, and through calculation, the number of the intermittent gas making operation is reduced by one while the production load is met, so that the raw material consumption and the steam consumption can be effectively saved, and the energy-saving benefit is considerable. The gas production rate of a single furnace is 7000-7200Nm/h, the steam consumption of the single furnace is 4.2 t/h, and the raw material coal consumption of a batch furnace per ton of ammonia is 1100kg. After the system designed by the utility model is changed, the gas production rate of a single furnace can reach 8000-8200Nm/h, the single furnace consumes 3.2 t/h of steam, and the consumption of raw material coal is 980kg; the gas production of a single furnace is increased by about 1000Nm/h, the steam consumption of the single furnace is reduced by 1t/h, and the ammonia consumption of raw material coal is reduced by 120kg. The continuous pure oxygen gasification technology is adopted for gas production, so that the gasification decomposition temperature of steam in the furnace can be increased, the steam conversion rate is increased, and the steam consumption is saved. The continuous gasification of pure oxygen not only increases the gas production, but also discharges waste gas in a non-blowing stage, greatly improves the environmental protection aspect, reduces the operation load of the three waste furnaces and the standard emission of environmental protection data, and has considerable generated environmental benefit, high efficiency, energy saving, low consumption, safety and environmental protection.
Drawings
Fig. 1 is a schematic structural diagram of the present invention.
The figures are labeled as follows: 1-a steam buffer tank, 2-a low-pressure steam pipe, 3-a gas mixing tank, 4-a gasifying agent pipe, 5-a pure oxygen furnace, 6-an automatic coal feeder, 7-a water-gas pipe, 8-a cyclone dust collector, 9-a heat pipe waste heat boiler, 10-a water seal tank, 11-a system waste heat recoverer, 12-a cooling pipe, 13-a gas cooler, 14-a heat pipe boiler steam drum, 15-a jacket steam drum, 16-an emptying valve and 17-a preheater.
Detailed Description
The following describes embodiments of the present invention with reference to the drawings.
The following examples are given.
A pure oxygen continuous gasification system, as shown in figure 1: the entry of steam buffer tank 1 has connect low pressure steam pipe 2, steam comes from outer pipe network and produces steam certainly, the export of steam buffer tank 1 passes through the steam pipe and mixes 3 middle part access connections of gas pitcher, the bottom import of mixing gas pitcher 3 has connect gasification agent pipe 4, gasification agent pipe 4 leads to there is the oxygen that connects from air separation plant purity to be 99.6%, gasification agent oxygen mixes in mixing gas pitcher 3 through measurement and proportion adjustment with low pressure steam, the exit linkage of mixing gas pitcher 3 is to the bottom import of pure oxygen stove 5, adopt the special grate of pure oxygen stove in the pure oxygen stove 5, through grate evenly distributed, the stove bottom both sides are provided with ash discharging device under the incessant stove, it is equipped with two ash storehouses to control, and have the circulating water, be used for ash storehouse adds water, raise dust when preventing to discharge ash, ash storehouse links to each other with steam buffer tank 1 through steam replacement pipe, be used for replacing steam. The top raw material inlet of the pure oxygen furnace 5 is connected with the raw material outlet of the automatic coal feeder 6, small coke particles or small coal blocks of raw materials enter the automatic coal feeder from a coal bunker, the raw materials are automatically added into the pure oxygen furnace 5 in a timed and quantitative manner, a pressurizing and pressure relieving device is arranged on the automatic coal feeder 6, mixed gas with the temperature controlled to 200 ℃ reacts with carbon burned in the furnace at high temperature to generate qualified water gas, the reaction is continuously carried out, water gas is continuously produced, a jacket steam pocket 15 is arranged above the pure oxygen furnace 5, the jacket steam pocket 15 is connected with the pure oxygen furnace 5 through an inlet and outlet pipeline, the jacket steam pocket 15 is connected with boiler deoxygenated water, the jacket steam pocket is connected to a steam buffer tank 1 through a circulating pipeline, the pressure of by-produced steam is improved, the design pressure of the jacket steam pocket 15 is 1.5MPa, the steam with the pressure of 1.1MPa can be generated, the superheated steam can be decompressed into self-use, energy is fully utilized, the cold wall effect is reduced, the furnace wall temperature is improved, the furnace wall temperature is further, and the coal gas yield is increased; a water gas pipe 7 is connected to a water gas outlet at the upper part of the pure oxygen furnace 5, the temperature of water gas generated by reaction ranges from 420 ℃ to 450 ℃, the water gas is discharged from the pure oxygen furnace 5, the water gas pipe 7 is connected to an inlet at the upper part of a cyclone dust collector 8 for dust removal, an air release valve 16 is arranged at the top of the cyclone dust collector 8, an outlet at the top of the cyclone dust collector 8 is connected with a preheater 17, the top of the preheater 17 is connected with an inlet at the top of a heat pipe waste heat boiler 9, a heat pipe boiler steam pocket 14 is arranged above the heat pipe waste heat boiler 9, one side of the heat pipe boiler steam pocket 14 is connected to the heat pipe waste heat boiler 9 through two inlet and outlet pipelines, the other side of the heat pipe boiler steam pocket 14 is connected to the preheater 17 at the top of the cyclone dust collector 8 through two inlet and outlet pipelines, a water seal tank 10 is connected to the bottom outlet of the heat pipe waste heat boiler 9 through a pipeline, the water seal tank 10 is connected to circulating water for safe water sealing, the water seal tank 10 is connected to an inlet at the top of a waste heat recovery system waste heat recovery 11 through a pipeline, a bottom outlet of the waste heat recovery 11 is connected to an inlet at the bottom of the system waste heat recovery device 13 through a cooling pipe 12, a cooling pipe 12 is connected to an inlet at the bottom of a gas cooler 13, a cooling pipe 12, a gas intercooling device 12 is connected to a gas main pipe, and a gas branch 13. The waste heat of the process is fully recovered, and the aim of saving energy is fulfilled.
When in use, the raw material small coke or small coal with the coal granularity requirement of 20-40mm hard blocks enters an automatic coal feeder 6 from a coal bunker, and is automatically fed into the furnace through a raw material inlet at the top of the pure oxygen furnace in a timed and quantitative manner; gasifying agent oxygen for gas production comes from an air separation process, the air separation oxygen content is 7000 Nm/h, the design pressure is 120Kpa, the oxygen enters a gas mixing tank 3 through a gasifying agent pipe 4, steam comes from an outer pipe network and self-produced steam enters from an inlet in the middle of the gas mixing tank 3 through a low-pressure steam pipe 2, the mixed gas temperature is controlled to be 200 ℃ and enters from an inlet in the bottom of a pure oxygen furnace 5, and oxidation-reduction reaction is carried out on the mixed gas and small coke or small coal under the high-temperature condition in the furnace to continuously produce water gas; the water gas generated by the reaction is discharged from a water gas outlet at the upper part of a pure oxygen furnace 5 through a water gas pipe 7, is dedusted by a cyclone deduster 8, enters a heat pipe waste heat boiler 9 through a preheater 17 from a top inlet, recovers the gas after the waste heat of the high-temperature gas, ensures safety through a bottom water seal tank 10, enters a system waste heat recoverer 11 from the top inlet, is discharged from a bottom outlet of the system waste heat recoverer 11 at the temperature of about 150 to 170 ℃, enters an indirect cooling device, greatly reduces the amount of cooling water due to the reduction of the gas temperature entering a washing tower through the waste heat recovery and utilization of the previous two stages, reduces the power consumption, and enters a water gas main pipe after being cooled by a gas cooler 13.
The gas production rate of a single furnace is 7000-7200Nm/h, the steam consumption of the single furnace is 4.2 t/h, the raw material coal consumption per ton ammonia of the intermittent furnace is 1100kg, after the system is changed, the gas production rate of the single furnace can reach 8000-8200Nm/h, the steam consumption of the single furnace is 3.2 t/h, and the raw material coal consumption is 980kg; the gas production of a single furnace is increased by about 1000Nm/h, the steam consumption of the single furnace is reduced by 1t/h, and the ammonia consumption of raw material coal is reduced by 120kg.
The scope of the invention is not limited to the above embodiments, and various modifications and changes may be made by those skilled in the art, and any modifications, improvements and equivalents made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.
Claims (7)
1. A pure oxygen continuous gasification system is characterized in that: the device comprises a steam buffer tank (1), wherein an inlet of the steam buffer tank (1) is connected with a low-pressure steam pipe (2), an outlet of the steam buffer tank (1) is connected with a middle inlet of a gas mixing tank (3) through a steam pipe, a bottom inlet of the gas mixing tank (3) is connected with a gasifying agent pipe (4), an outlet of the gas mixing tank (3) is connected to a bottom inlet of a pure oxygen furnace (5), a top raw material inlet of the pure oxygen furnace (5) is connected with a raw material outlet of an automatic coal feeder (6), an upper water gas outlet of the pure oxygen furnace (5) is connected with a water gas pipe (7), the water pipe (7) is connected to an upper inlet of a cyclone dust collector (8), the top outlet of the cyclone dust collector (8) is connected with a preheater (17), the top inlet of a waste heat pipe boiler (9) is connected with the top of the preheater (17), a bottom outlet of the heat pipe waste heat pipe boiler (9) is connected with a water seal tank (10) through a pipeline, the water seal tank (10) is connected with a top inlet of a waste heat recovery device (11) through a pipeline connection system waste heat recovery device (11), and a cooling pipe (13) is connected with a cooling main pipe (13), and a cooling device is connected with a cooling main pipe (13) and communicated with the upper inlet of the coal gas inlet of the cooling device.
2. The pure oxygen continuous gasification system according to claim 1, wherein: a heat pipe boiler steam drum (14) is arranged above the heat pipe waste heat boiler (9), one side of the heat pipe boiler steam drum (14) is connected to the heat pipe waste heat boiler (9) through an inlet and outlet two pipelines, and the other side of the heat pipe boiler steam drum (14) is connected to a top preheater (17) of the cyclone dust collector (8) through an inlet and outlet two pipelines.
3. The pure oxygen continuous gasification system according to claim 1, wherein: the pure oxygen boiler is characterized in that a jacket steam drum (15) is arranged above the pure oxygen boiler (5), the jacket steam drum (15) is connected with the pure oxygen boiler (5) through an inlet and outlet pipeline, the jacket steam drum (15) is connected with boiler deoxygenated water, and the jacket steam drum is connected to the steam buffer tank (1) through a circulating pipeline.
4. A pure oxygen continuous gasification system according to claim 1, wherein: and a pressurizing and pressure-relieving device is arranged on the automatic coal feeder (6).
5. The pure oxygen continuous gasification system according to claim 1, wherein: a special grate for the pure oxygen furnace is adopted in the pure oxygen furnace, and non-stop ash discharging devices are arranged on two sides of the furnace bottom.
6. The pure oxygen continuous gasification system according to claim 1, wherein: the gasifying agent pipe (4) is communicated with oxygen connected with an air separation device.
7. A pure oxygen continuous gasification system according to claim 1, wherein: an emptying valve (16) is arranged at the top of the cyclone dust collector (8).
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CN202221951168.7U CN218435600U (en) | 2022-07-27 | 2022-07-27 | Pure oxygen continuous gasification system |
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CN202221951168.7U CN218435600U (en) | 2022-07-27 | 2022-07-27 | Pure oxygen continuous gasification system |
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