High-temperature thermal reforming system and method for biomass gasification crude synthesis gas

Abstract

The invention discloses a high-temperature thermal reforming system and method for biomass gasification crude synthesis gas, and belongs to the technical field of energy utilization. The device comprises a synthesis gas washing tower, a heat exchanger, a synthesis gas high-temperature thermal reforming reactor, a radiation boiler and a reformed gas washing tower, crude synthesis gas generated by biomass gasification enters a crude synthesis gas washing tower, enters a heat exchanger for preheating after being cooled, dedusted, detarred and humidified by the washing tower, then enters a high-temperature thermal reforming reactor with oxygen from the top, and is subjected to partial combustion and high-temperature reforming reaction in the reactor, so that methane is converted into CO and H2; the synthesis gas after high-temperature reforming is cooled by the radiation boiler, and then returns to the heat exchanger to exchange heat with the gas at the outlet of the water scrubber; the gas cooled by the heat exchanger enters a reformed gas washing tower to be washed, and reformed synthesis gas is obtained. According to the invention, the problem of methane reforming conversion in the biomass gasification product is solved, and the target of flexibly adjusting the hydrogen-carbon ratio of the synthesis gas can be achieved.

Description

Technical Field

[0001] The invention belongs to the technical field of energy utilization, and in particular relates to a high-temperature thermal reforming system and method for raw synthesis gas from biomass gasification. Background Art

[0002] In the context of carbon neutrality, carbon reduction has become a major theme in the development of human society. Green methanol is known as "liquid sunshine" and is also the best storage and transportation carrier for green hydrogen. The production and use of green methanol is an important way to achieve carbon reduction goals.

[0003] Biomass gasification to produce syngas is an important part of the green methanol production process. However, the crude syngas produced by biomass gasification usually has a high methane content and carries a trace amount of tar. The hydrogen-carbon ratio in the crude syngas is not the optimal ratio for synthesizing methanol (the hydrogen-carbon ratio of methanol synthesis is generally 2.05-2.15). The high methane content reduces the economic efficiency of the methanol synthesis process, and the presence of tar will seriously affect the stability of equipment operation. Obviously, in order to obtain a reliable technology for preparing methanol from biomass gasification, it is necessary to develop a crude syngas thermal conversion method that is simple and efficient, has a directional adjustable hydrogen-carbon ratio, and selectively converts methane.

[0004] At present, non-catalytic partial oxidation technology is widely used in the field of natural gas and coke oven gas to convert methane components into synthesis gas (CO and H2). Among them, the components and composition of coke oven gas and crude synthesis gas from biomass gasification are similar. Therefore, the high-temperature thermal reforming process used in non-catalytic partial oxidation technology can be used to achieve the purpose of converting methane and trace tar in crude synthesis gas. However, the methane content in coke oven gas is generally 23% to 27%, which is significantly higher than the methane content in crude synthesis gas from biomass gasification. There is also a significant difference in the ratio of CO and CO2. Therefore, the conversion temperature and operating conditions of the high-temperature thermal reforming method of crude synthesis gas from biomass gasification will also be significantly different. In addition, how to couple biomass gasification with the high-temperature thermal reforming process of crude synthesis gas to reduce the heat loss of the entire process is also the key to affecting the thermal efficiency of biomass gasification.

[0005] To this end, it is necessary to optimize the high-temperature thermal reforming process according to the biomass gasification process and the composition characteristics of the crude syngas, and develop a method with controllable hydrogen-to-carbon ratio, simple operation and high thermal efficiency to achieve the goal of preparing high hydrogen-to-carbon ratio syngas from biomass. Summary of the invention

[0006] Several major technical problems in the existing biomass gasification technology for preparing green methanol are addressed: First, the methane component in the biomass gasification crude synthesis gas is difficult to use directly, and the hydrogen-carbon ratio is relatively low; second, the presence of dust and tar will clog the equipment and pipelines and affect the stability of the system operation; third, the existing coke oven gas high-temperature thermal reforming process has low thermal efficiency and poor economy when directly using the heat. This method provides a high-temperature thermal reforming system and method for biomass gasification crude synthesis gas, and optimizes the high-temperature thermal reforming method and process for biomass gasification crude synthesis gas, including purifying the crude synthesis gas produced by biomass gasification, flexibly adjusting the amount of water vapor required for the high-temperature thermal reforming reaction, and improving the heat exchange route of the high-temperature thermal reforming system, thereby reducing the heat loss of the high-temperature thermal reforming process of biomass gasification crude synthesis gas, improving the thermal efficiency, and improving the reliability and stability of the thermal reforming system and the subsequent system operation.

[0007] In order to achieve the above object, the present invention adopts the following technical solutions:

[0008] A high temperature thermal reforming system and method for biomass gasification raw synthesis gas, comprising:

[0009] Crude syngas water scrubber, heat exchanger, syngas high temperature thermal reforming reactor, radiant boiler and reformed gas water scrubber;

[0010] A crude synthesis gas inlet for the water scrubber is provided at the lower part of the crude synthesis gas water scrubber, and a crude synthesis gas outlet for the water scrubber is provided at the upper part of the crude synthesis gas water scrubber; the heat exchanger is provided with a heat exchanger inlet and a heat exchanger outlet, as well as a reforming gas inlet and a reforming gas outlet; a high-temperature resistant gas nozzle is provided at the top of the synthesis gas high-temperature thermal reforming reactor, and a high-temperature reforming gas outlet is provided at the bottom; a radiation boiler inlet is provided at the top of the radiation boiler, and a radiation boiler outlet is provided at the bottom; a high-pressure water inlet and a high-pressure steam outlet are provided on the side wall; a reforming gas water scrubber is provided with a reforming gas water scrubber inlet at the bottom, and a reforming gas water scrubber outlet is provided at the upper part;

[0011] The crude synthesis gas outlet of the water scrubber is connected to the air inlet of the heat exchanger; the air outlet of the heat exchanger is connected to the high-temperature resistant gas nozzle; the high-temperature reformed gas outlet is connected to the air inlet of the radiation boiler: the air outlet of the radiation boiler is connected to the reformed gas inlet; the reformed gas outlet is connected to the air inlet of the reformed gas water scrubber.

[0012] Furthermore, the high temperature resistant gas nozzle is a dual-channel nozzle, including a nozzle inner channel and a nozzle annular gap channel.

[0013] Furthermore, the synthesis gas high temperature thermal reforming reactor consists of a combustion zone and a reduction zone, which are respectively distributed from top to bottom in the reactor.

[0014] Furthermore, a cooling water inlet and a cooling water outlet are provided at the upper part of the crude synthesis gas water scrubber, and the cooling water flows from top to bottom; it is used for heat exchange in the crude synthesis gas water scrubber, and at the same time, removes impurities in the crude synthesis gas and adjusts the humidity;

[0015] Furthermore, the reformed gas water washing tower is provided with a high-pressure cooling water inlet at the top and a high-pressure cooling water outlet at the bottom, and the high-pressure cooling water flows from top to bottom; and is used for heat exchange in the reformed gas water washing tower.

[0016] Furthermore, a high-pressure water inlet and a high-pressure steam outlet are provided on the side wall of the radiation boiler for heat exchange in the radiation boiler.

[0017] A high temperature thermal reforming method of biomass gasification crude synthesis gas based on the above system comprises the following steps:

[0018] Step 1, the crude synthesis gas generated by biomass gasification is recovered by a waste heat boiler and then enters a crude synthesis gas water scrubber from the crude synthesis gas inlet at the bottom of the water scrubber, and is fully contacted with cooling water from the cooling water inlet in the crude synthesis gas water scrubber. The cooling water is discharged from the cooling water outlet at the bottom of the tower, and the ash, alkali metals and trace tar in the crude synthesis gas are effectively removed; after washing, the gas temperature at the crude synthesis gas outlet of the water scrubber is reduced to 40°C to 150°C; the specific gas temperature at the crude synthesis gas outlet of the water scrubber is determined according to the amount of water vapor (humidity adjustment) required for the high-temperature thermal reforming reaction occurring inside the synthesis gas high-temperature thermal reforming reactor;

[0019] Step 2, the gas at the outlet of the crude syngas of the water scrubber enters the heat exchanger from the air inlet of the heat exchanger for preheating; the heat exchanger recovers the waste heat in the reformed gas at the outlet of the radiation boiler, and enters the heat exchanger from the air inlet of the reformed gas; after heat exchange, the temperature of the outlet gas of the crude syngas water scrubber is raised to 500°C to 650°C, and then enters the syngas high-temperature thermal reforming reactor through the high-temperature resistant gas nozzle;

[0020] Step 3: The crude synthesis gas preheated by the heat exchanger enters the synthesis gas high-temperature thermal reforming reactor through the nozzle annular gap channel of the high-temperature resistant gas nozzle, and is fully mixed with the gasifying agent flowing into the inner channel of the nozzle at the outlet of the high-temperature resistant gas nozzle; then, partial combustion and high-temperature reforming reactions occur inside the synthesis gas high-temperature thermal reforming reactor to convert methane into CO and H2, and the reformed gas generated by the reaction is discharged from the high-temperature reformed gas outlet at the bottom of the reactor;

[0021] Step 4: The high-temperature reformed gas at the outlet of the syngas high-temperature thermal reforming reactor enters the radiant boiler from the radiant boiler air inlet for waste heat recovery and is output from the radiant boiler air outlet; the reformed gas temperature drops from 1100°C to 1350°C at the radiant boiler inlet to 750°C to 850°C at the outlet; high-pressure water enters the radiant boiler from the high-pressure water inlet and the by-product high-pressure saturated steam is discharged from the high-pressure steam outlet;

[0022] Step 5: The reformed gas from the radiation boiler enters the heat exchanger from the reformed gas inlet for further heat recovery, exchanges heat with the gas at the outlet of the crude synthesis gas scrubber, and then is discharged from the reformed gas outlet; after the waste heat is recovered, the temperature of the reformed gas at the outlet of the radiation boiler drops from 750°C to 850°C at the inlet of the heat exchanger to 150°C to 250°C at the outlet;

[0023] Step 6: The reformed gas cooled by the heat exchanger enters the reformed gas water washing tower from the air inlet of the reformed gas water washing tower for washing and is cooled by high-pressure cooling water; its temperature is further reduced to 30°C to 60°C to obtain synthesis gas for methanol synthesis, and then discharged from the outlet of the reformed gas water washing tower.

[0024] Furthermore, the crude synthesis gas entering the crude synthesis gas water scrubber has a water content of 10% to 60%, a methane content of 5% to 15%, a CO2 content of 20% to 45%, and a tar content of less than 10 g / Nm 3 ; The temperature is 150℃~250℃.

[0025] Furthermore, the reaction temperature of the synthesis gas high temperature thermal reforming reactor is 1100° C. to 1350° C., and the pressure is 0.1 to 4 MPa.

[0026] Furthermore, the gasifying agent is a mixed gas of O2 / water vapor or O2 / CO2.

[0027] Furthermore, the molar ratio of O2 contained in the gasifying agent to the raw synthesis gas is 0.10 to 0.35.

[0028] Compared with the prior art, the present invention has the following advantages:

[0029] 1. The present invention can directly process gaseous hydrocarbon mixed gas with low methane content, and the methane content is 5-15%.

[0030] 2. The biomass gasification crude synthesis gas of the present invention contains a relatively high moisture content, which can be used to provide the steam required for high-temperature thermal reforming reaction, thereby achieving self-sufficiency of reforming water vapor, and the amount of water vapor used can be adjusted by a water scrubber.

[0031] 3. The process flow of the present invention is simple, and the heat of the high-temperature reformed synthetic gas is fully recovered through the radiation boiler, the crude synthesis gas and the reformed gas heat exchanger, while high-pressure saturated steam is produced as a by-product, thereby achieving reasonable utilization of heat and high thermal efficiency.

[0032] 4. The raw gas used in the present invention is clean gas washed by a water scrubber, which contains almost no dust, alkali metals and tar, thereby reducing the harm to the high-temperature thermal reforming reactor and the subsequent system and reducing the equipment failure rate.

[0033] 5. The synthesis gas inlet temperature of the high-temperature thermal reforming reactor developed by the present invention is relatively low and contains fewer impurities, which reduces the damage to the gas nozzle. Therefore, there is no special restriction on the material of the gas nozzle, and the service life of the nozzle is extended. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 A high temperature thermal reforming process flow chart of biomass gasification crude synthesis gas in the present invention;

[0035] Figure 2 Schematic diagram of the structure of heat exchanger 2;

[0036] Figure 3 Schematic diagram of the structure of the reforming reactor 3;

[0037] Figure 4 Schematic diagram of the structure of the radiation boiler 4;

[0038] Figure 5 Schematic diagram of the structure of nozzle 10.

[0039] Figure numerals: 1. crude synthesis gas water scrubber; 2. heat exchanger; 3. synthesis gas high-temperature thermal reforming reactor; 4. radiation boiler; 5. reforming gas water scrubber; 6. crude synthesis gas inlet of water scrubber; 7. crude synthesis gas outlet of water scrubber; 8. heat exchanger inlet; 9. heat exchanger outlet; 10. high temperature resistant gas nozzle; 11. high temperature reforming gas outlet; 12. radiation boiler inlet; 13. radiation boiler outlet; 14. reforming gas inlet; 15. reforming gas outlet; 16. reforming gas water scrubber inlet; 17. reforming gas water scrubber outlet; 18. cooling water inlet; 19. cooling water outlet; 20. high-pressure cooling water inlet; 21. high-pressure cooling water outlet; 22. high-pressure water inlet; 23. high-pressure steam outlet; 24. nozzle inner side channel; 25. nozzle annular gap channel; 26. combustion zone; 27. reduction zone. DETAILED DESCRIPTION

[0040] In order to gain a deeper understanding of the present invention, we will provide a comprehensive and detailed description of the present invention. However, the present invention has multiple implementations and is not limited to the specific examples listed herein. The presentation of these examples is intended to deepen the comprehensive understanding of the disclosure of the present invention.

[0041] like Figure 1 As shown, a high temperature thermal reforming system for raw synthesis gas from biomass gasification.

[0042] It includes: a crude synthesis gas water washing tower 1, a heat exchanger 2, a synthesis gas high temperature thermal reforming reactor 3, a radiation boiler 4 and a reformed gas water washing tower 5;

[0043] A water-washing tower crude synthesis gas inlet 6 is provided at the lower part of the crude synthesis gas water-washing tower 1, and a water-washing tower crude synthesis gas outlet 7 is provided at the upper part of the crude synthesis gas water-washing tower 1; the heat exchanger is provided with a heat exchanger inlet 8 and a heat exchanger outlet 9, as well as a reforming gas inlet 14 and a reforming gas outlet 15; the top of the synthesis gas high-temperature thermal reforming reactor 3 is provided with a high-temperature resistant gas nozzle 10, and the bottom is provided with a high-temperature reforming gas outlet 11; the top of the radiation boiler 4 is provided with a radiation boiler inlet 12, and the bottom is provided with a radiation boiler outlet 13; the side wall is provided with a high-pressure water inlet 22 and a high-pressure steam outlet 23; the reforming gas water-washing tower 5 is provided with a reforming gas water-washing tower inlet 16 at the bottom, and a reforming gas water-washing tower outlet 17 at the upper part;

[0044] The raw synthesis gas outlet 7 of the water scrubber is connected to the heat exchanger inlet 8; the heat exchanger outlet 9 is connected to the high temperature resistant gas nozzle 10; the high temperature reformed gas outlet 11 is connected to the radiation boiler inlet 12; the radiation boiler outlet 13 is connected to the reformed gas inlet 14; the reformed gas outlet 15 is connected to the reformed gas water scrubber inlet 16.

[0045] Furthermore, the high temperature resistant gas nozzle 10 is a dual-channel nozzle, including a nozzle inner channel 24 and a nozzle annular gap channel 25 .

[0046] Furthermore, the synthesis gas high temperature thermal reforming reactor 3 is composed of a combustion zone 26 and a reduction zone 27, which are respectively distributed from top to bottom in the reactor.

[0047] Furthermore, the gasifying agent is a mixed gas of O2 / water vapor or O2 / CO2.

[0048] Furthermore, a cooling water inlet 18 and a cooling water outlet 19 are provided at the upper part of the crude synthesis gas water scrubber 1, and the cooling water flows from top to bottom; it is used for heat exchange in the crude synthesis gas water scrubber 1, and at the same time, removes impurities in the crude synthesis gas and adjusts the humidity;

[0049] Furthermore, the reformed gas water washing tower 5 is provided with a high-pressure cooling water inlet 20 at the top and a high-pressure cooling water outlet 21 at the bottom, and the high-pressure cooling water flows from top to bottom for heat exchange in the reformed gas water washing tower 5 .

[0050] Furthermore, a high-pressure water inlet 22 and a high-pressure steam outlet 23 are provided on the side wall of the radiation boiler 4 for heat exchange in the radiation boiler 4 .

[0051] A high-temperature thermal reforming method for biomass gasification crude synthesis gas.

[0052] The method is implemented in a high-temperature thermal reforming system of biomass gasification crude synthesis gas, and the specific steps are as follows:

[0053] Step 1, the crude synthesis gas generated by biomass gasification is recovered by the waste heat boiler and then enters the crude synthesis gas water scrubber 1 from the crude synthesis gas inlet 6 of the water scrubber at the bottom, and is fully contacted with the cooling water from the cooling water inlet 18 in the crude synthesis gas water scrubber 1. The cooling water is discharged from the cooling water outlet 19 at the bottom of the tower, and the ash, alkali metals and trace tar in the crude synthesis gas are effectively removed; after washing, the gas temperature of the crude synthesis gas outlet 7 of the water scrubber is reduced to 40°C to 150°C; the specific gas temperature of the crude synthesis gas outlet 7 of the water scrubber is determined according to the amount of water vapor (humidity adjustment) required for the high-temperature thermal reforming reaction occurring inside the synthesis gas high-temperature thermal reforming reactor 3;

[0054] Step 2, the gas from the crude synthesis gas outlet 7 of the water scrubber enters the heat exchanger 2 from the heat exchanger inlet 8 for preheating; the heat exchanger 2 recovers the waste heat in the reformed gas at the outlet of the radiation boiler 4, and enters the heat exchanger 2 from the reformed gas inlet 14; after heat exchange, the temperature of the crude synthesis gas outlet of the water scrubber 1 is raised to 500°C to 650°C, and then enters the synthesis gas high-temperature thermal reforming reactor 3 through the high-temperature resistant gas nozzle 10;

[0055] Step 3: The raw synthesis gas preheated by the heat exchanger 2 enters the synthesis gas high-temperature thermal reforming reactor 3 through the nozzle annular gap channel 25 of the high-temperature resistant gas nozzle 10, and is fully mixed with the gasifying agent flowing into the nozzle inner channel 24 at the outlet of the high-temperature resistant gas nozzle 10; then, partial combustion and high-temperature reforming reactions occur inside the synthesis gas high-temperature thermal reforming reactor 3, converting methane into CO and H2 and a small amount of CO2, and the reformed gas generated by the reaction is discharged from the high-temperature reformed gas outlet 11 at the bottom of the reactor;

[0056] Step 4: The high-temperature reformed gas at the outlet of the synthesis gas high-temperature thermal reforming reactor 3 enters the radiation boiler 4 from the radiation boiler air inlet 12 for waste heat recovery and is output from the radiation boiler air outlet 13; the temperature of the reformed gas drops from 1100°C to 1350°C at the inlet of the radiation boiler 4 to 750°C to 850°C at the outlet; high-pressure water enters the radiation boiler 4 from the high-pressure water inlet 22, and the by-product high-pressure saturated steam is discharged from the high-pressure steam outlet 23;

[0057] Step 5: The reformed gas from the radiation boiler 4 enters the heat exchanger 2 through the reformed gas inlet 14 for further heat recovery, exchanges heat with the outlet gas of the crude synthesis gas scrubber 1, and then is discharged through the reformed gas outlet 15; after the waste heat is recovered, the temperature of the reformed gas at the outlet of the radiation boiler 4 is reduced from 750°C to 850°C at the inlet of the heat exchanger 2 to 150°C to 250°C at the outlet;

[0058] Step 6: The reformed gas cooled by the heat exchanger 2 enters the reformed gas water washing tower 5 from the reformed gas water washing tower air inlet 16 for washing and is cooled by high-pressure cooling water; its temperature is further reduced to 30°C to 60°C to obtain synthesis gas for methanol synthesis, and then discharged from the reformed gas water washing tower outlet 17.

[0059] The reaction temperature of the synthesis gas high temperature thermal reforming reactor 3 is 1100° C. to 1350° C., and the pressure is 0.1 to 4 MPa. The molar ratio of O2 delivered by the high temperature resistant gas nozzle 10 to the crude synthesis gas is 0.10 to 0.35.

[0060] The gasifying agent is a mixed gas of O2 / water vapor or O2 / CO2.

[0061] The following takes the crude synthesis gas prepared by forming corn straw pellets as raw materials as an example. The composition of the biomass gasification crude synthesis gas entering the crude synthesis gas water washing tower 1 is shown in Table 1, and the crude synthesis gas temperature is 200°C.

[0062] Table 1 Molar composition of biomass crude syngas

[0063] Components <![CDATA[H2%]]> CO% <![CDATA[CO2%]]> <![CDATA[CH4%]]> <![CDATA[H2O(g)%]]> <![CDATA[targ / Nm 3 ]]> content 15.84 8.92 20.46 4.78 50.00 10.00

[0064] Example 1

[0065] The biomass gasification crude synthesis gas entering the crude synthesis gas washing tower 1 shown in Table 1 is used as the raw gas, and the gasifying agent is O2 / water vapor. According to the above system and method, the specific implementation details are as follows:

[0066] The temperature of the outlet gas of the crude synthesis gas water scrubber 1 is 120°C, and after being preheated by the heat exchanger 2, the temperature is increased to 550°C.

[0067] The reaction temperature of the synthesis gas high temperature thermal reforming reactor 3 is 1200° C. and the reaction pressure is 1.0 MPa.

[0068] The molar ratio of O2 to the raw synthesis gas delivered in the high temperature resistant gas nozzle 10 is 0.15.

[0069] After the high-temperature reformed gas at the outlet of the synthesis gas high-temperature thermal reforming reactor 3 passes through the radiation boiler 4 for waste heat recovery, the temperature of the reformed gas is reduced from 1200° C. at the inlet of the radiation boiler 4 to 790° C. at the outlet.

[0070] The outlet gas of the radiation boiler 4 enters the heat exchanger 2 for further heat recovery. After the waste heat is recovered, the temperature of the reformed gas at the outlet of the radiation boiler 4 is reduced from 790°C to 180°C.

[0071] The reformed gas cooled by the heat exchanger 2 enters the reformed gas water washing tower 5 for washing and is cooled to 40°C.

[0072] The gas composition (dry basis) of the final outlet synthesis gas from the reformed gas water scrubber 5 is shown in Table 2.

[0073] Table 2 Example 1 outlet synthesis gas molar composition

[0074] Components <![CDATA[H2]]> CO <![CDATA[CO2]]> <![CDATA[CH4]]> total content,% 31.98 23.93 42.05 2.04 100.00

[0075] Example 2

[0076] Taking the biomass gasification crude synthesis gas entering the crude synthesis gas washing tower 1 shown in Table 1 as the raw gas, and the gasifying agent as O2 / water vapor, according to the above system and method, the specific implementation details of Example 2 are as follows:

[0077] The temperature of the outlet gas of the crude synthesis gas water scrubber 1 is 140°C, and after being preheated by the heat exchanger 2, the temperature is increased to 600°C.

[0078] The reaction temperature of the synthesis gas high temperature thermal reforming reactor 3 is 1200° C. and the reaction pressure is 1.0 MPa.

[0079] The molar ratio of O2 to the raw synthesis gas delivered in the high temperature resistant gas nozzle 10 is 0.14.

[0080] After the high-temperature reformed gas at the outlet of the synthesis gas high-temperature thermal reforming reactor 3 passes through the radiation boiler 4 for waste heat recovery, the temperature of the reformed gas is reduced from 1200° C. at the inlet of the radiation boiler 4 to 790° C. at the outlet.

[0081] The outlet gas of the radiation boiler 4 enters the heat exchanger 2 for further heat recovery. After the waste heat is recovered, the temperature of the reformed gas at the outlet of the radiation boiler 4 is reduced from 790°C to 200°C.

[0082] The reformed gas cooled by the heat exchanger 2 enters the reformed gas water washing tower 5 for washing and is cooled to 40°C.

[0083] The gas composition (dry basis) of the final outlet synthesis gas of the reformed gas water scrubber 5 is shown in Table 3.

[0084] Table 3 Example 2 outlet synthesis gas molar composition

[0085] Components <![CDATA[H2]]> CO <![CDATA[CO2]]> <![CDATA[CH4]]> total content,% 31.37 24.30 42.42 1.92 100.00

[0086] Example 3

[0087] Taking the biomass gasification crude synthesis gas entering the crude synthesis gas washing tower 1 shown in Table 1 as the raw gas, and the gasifying agent as O2 / water vapor, according to the above system and method, the specific implementation details of Example 3 are as follows:

[0088] The temperature of the outlet gas of the crude synthesis gas water scrubber 1 is 140°C, and after being preheated by the heat exchanger 2, the temperature is increased to 620°C.

[0089] The reaction temperature of the synthesis gas high temperature thermal reforming reactor 3 is 1300° C. and the reaction pressure is 1.0 MPa.

[0090] The molar ratio of O2 to the raw synthesis gas delivered in the high temperature resistant gas nozzle 10 is 0.21.

[0091] After the high-temperature reformed gas at the outlet of the synthesis gas high-temperature thermal reforming reactor 3 passes through the radiation boiler 4 for waste heat recovery, the temperature of the reformed gas is reduced from 1300° C. at the inlet of the radiation boiler 4 to 810° C. at the outlet.

[0092] The outlet gas of the radiation boiler 4 enters the heat exchanger 2 for further heat recovery. After the waste heat is recovered, the temperature of the reformed gas at the outlet of the radiation boiler 4 is reduced from 810°C to 220°C.

[0093] The reformed gas cooled by the heat exchanger 2 enters the reformed gas water washing tower 5 for washing and is cooled to 40°C.

[0094] The gas composition (dry basis) of the final outlet synthesis gas of the reformed gas water scrubber 5 is shown in Table 4.

[0095] Table 4 Example 3 outlet synthesis gas molar composition

[0096] Components <![CDATA[H2]]> CO <![CDATA[CO2]]> <![CDATA[CH4]]> total content,% 32.41 23.94 43.23 0.43 100.00

[0097] Example 4

[0098] Taking the biomass gasification crude synthesis gas entering the crude synthesis gas washing tower 1 shown in Table 1 as the raw gas, and the gasifying agent as O2 / water vapor, according to the above system and method, the specific implementation details of Example 4 are as follows:

[0099] The temperature of the outlet gas of the crude synthesis gas water scrubber 1 is 150°C, and after being preheated by the heat exchanger 2, the temperature is increased to 650°C.

[0100] The reaction temperature of the synthesis gas high temperature thermal reforming reactor 3 is 1300° C. and the reaction pressure is 4.0 MPa.

[0101] The molar ratio of O2 to the raw synthesis gas delivered in the high temperature resistant gas nozzle 10 is 0.19.

[0102] After the high-temperature reformed gas at the outlet of the synthesis gas high-temperature thermal reforming reactor 3 passes through the radiation boiler 4 for waste heat recovery, the temperature of the reformed gas is reduced from 1300° C. at the inlet of the radiation boiler 4 to 820° C. at the outlet.

[0103] The outlet gas of the radiation boiler 4 enters the heat exchanger 2 for further heat recovery. After the waste heat is recovered, the temperature of the reformed gas at the outlet of the radiation boiler 4 is reduced from 820°C to 230°C.

[0104] The reformed gas cooled by the heat exchanger 2 enters the reformed gas water washing tower 5 for washing and is cooled to 40°C.

[0105] The gas composition (dry basis) of the final outlet synthesis gas of the reformed gas water scrubber 5 is shown in Table 5.

[0106] Table 5 Example 4 outlet synthesis gas molar composition

[0107] Components <![CDATA[H2]]> CO <![CDATA[CO2]]> <![CDATA[CH4]]> total content,% 32.16 24.24 42.93 0.68 100.00

[0108] Example 5

[0109] Taking the biomass gasification crude synthesis gas entering the crude synthesis gas washing tower 1 shown in Table 1 as the raw gas, and the gasifying agent as O2 / CO2, according to the above system and method, the specific implementation details of Example 5 are as follows:

[0110] The temperature of the outlet gas of the crude synthesis gas water scrubber 1 is 140°C, and after being preheated by the heat exchanger 2, the temperature is increased to 600°C.

[0111] The reaction temperature of the synthesis gas high temperature thermal reforming reactor 3 is 1200° C. and the reaction pressure is 1.0 MPa.

[0112] The molar ratio of O2 to the raw synthesis gas delivered in the high temperature resistant gas nozzle 10 is 0.14.

[0113] After the high-temperature reformed gas at the outlet of the synthesis gas high-temperature thermal reforming reactor 3 passes through the radiation boiler 4 for waste heat recovery, the temperature of the reformed gas is reduced from 1200° C. at the inlet of the radiation boiler 4 to 790° C. at the outlet.

[0114] The outlet gas of the radiation boiler 4 enters the heat exchanger 2 for further heat recovery. After the waste heat is recovered, the temperature of the reformed gas at the outlet of the radiation boiler 4 is reduced from 790°C to 200°C.

[0115] The reformed gas cooled by the heat exchanger 2 enters the reformed gas water washing tower 5 for washing and is cooled to 40°C.

[0116] The gas composition (dry basis) of the final outlet synthesis gas of the reformed gas water scrubber 5 is shown in Table 6.

[0117] Table 6 Example 5 outlet synthesis gas molar composition

[0118] Components <![CDATA[H2]]> CO <![CDATA[CO2]]> <![CDATA[CH4]]> total content,% 27.20 24.75 46.37 1.68 100.00

[0119] The contents not described in detail in the specification of the present invention belong to the prior art known to the professional and technical personnel in the field. Although the illustrative specific embodiments of the present invention are described above to facilitate the understanding of the present invention by the technical personnel in the field, it should be clear that the present invention is not limited to the scope of the specific embodiments. For the ordinary technical personnel in the field, as long as various changes are within the spirit and scope of the present invention defined and determined by the attached claims, these changes are obvious, and all inventions and creations using the concept of the present invention are protected.

Claims

1. A high temperature thermal reforming system for raw synthesis gas from biomass gasification, characterized in that: include: A crude synthesis gas water scrubber (1), a heat exchanger (2), a synthesis gas high temperature thermal reforming reactor (3), a radiation boiler (4) and a reformed gas water scrubber (5); A water scrubber crude synthesis gas inlet (6) is provided at the lower part of the crude synthesis gas water scrubber (1), and a water scrubber crude synthesis gas outlet (7) is provided at the upper part of the crude synthesis gas water scrubber (1); the heat exchanger is provided with a heat exchanger inlet (8) and a heat exchanger outlet (9), as well as a reforming gas inlet (14) and a reforming gas outlet (15); a high temperature resistant gas nozzle (10) is provided at the top of the synthesis gas high temperature thermal reforming reactor (3), and a high temperature reforming gas outlet (11) is provided at the bottom; a radiation boiler inlet (12) is provided at the top of the radiation boiler (4), and a radiation boiler outlet (13) is provided at the bottom; a high pressure water inlet (22) and a high pressure steam outlet (23) are provided on the side wall; a reforming gas water scrubber is provided with a reforming gas water scrubber inlet (16) at the bottom, and a reforming gas water scrubber outlet (17) is provided at the upper part of the reforming gas water scrubber (5); The crude synthesis gas outlet (7) of the water scrubber is in communication with the heat exchanger inlet (8); the heat exchanger outlet (9) is in communication with the high temperature resistant gas nozzle (10); the high temperature reformed gas outlet (11) is in communication with the radiation boiler inlet (12); the radiation boiler outlet (13) is in communication with the reformed gas inlet (14); the reformed gas outlet (15) is in communication with the reformed gas water scrubber inlet (16).

2. The high temperature thermal reforming system of biomass gasification crude synthesis gas according to claim 1, characterized in that: The high temperature resistant gas nozzle (10) is a double-channel nozzle, comprising a nozzle inner channel (24) and a nozzle annular gap channel (25).

3. A high temperature thermal reforming system and method for raw synthesis gas from biomass gasification according to claim 1, characterized in that: The synthesis gas high temperature thermal reforming reactor (3) consists of a combustion zone (26) and a reduction zone (27), which are respectively distributed from top to bottom in the reactor.

4. The high temperature thermal reforming system of biomass gasification crude synthesis gas according to claim 1, characterized in that: The crude synthesis gas water scrubber (1) is provided with a cooling water inlet (18) and a cooling water outlet (19) at the top, and the cooling water flows from top to bottom; the cooling water is used for heat exchange in the crude synthesis gas water scrubber (1), while removing impurities in the crude synthesis gas and adjusting the humidity; The reformed gas water washing tower (5) is provided with a high-pressure cooling water inlet (20) at the top and a high-pressure cooling water outlet (21) at the bottom, and the high-pressure cooling water flows from top to bottom; it is used for heat exchange in the reformed gas water washing tower (5).

5. The high temperature thermal reforming system of biomass gasification crude synthesis gas according to claim 1, characterized in that: A high-pressure water inlet (22) and a high-pressure steam outlet (23) are provided on the side wall of the radiation boiler (4) for heat exchange in the radiation boiler (4).

6. A high temperature thermal reforming method of biomass gasification crude synthesis gas based on the system according to any one of claims 1 to 5, characterized in that: The following steps are involved: Step 1, the crude synthesis gas generated by biomass gasification is recovered by a waste heat boiler and then enters a crude synthesis gas water scrubber (1) from a crude synthesis gas inlet (6) at the bottom of the water scrubber, and is fully in contact with cooling water from a cooling water inlet (18) in the crude synthesis gas water scrubber (1). The cooling water is discharged from a cooling water outlet (19) at the bottom of the tower, and ash, alkali metals and trace tar in the crude synthesis gas are effectively removed; after washing, the gas temperature at the crude synthesis gas outlet (7) of the water scrubber is reduced to 40°C to 150°C; the specific gas temperature at the crude synthesis gas outlet (7) of the water scrubber is determined according to the amount of water vapor required for the high-temperature thermal reforming reaction occurring inside the synthesis gas high-temperature thermal reforming reactor (3); Step 2, the gas at the outlet (7) of the water scrubber enters the heat exchanger (2) from the heat exchanger inlet (8) for preheating; the heat exchanger (2) recovers the waste heat in the reformed gas at the outlet of the radiation boiler (4), and enters the heat exchanger (2) from the reformed gas inlet (14); after heat exchange, the outlet gas of the water scrubber (1) of the crude synthesis gas is heated to 500° C. to 650° C., and then enters the synthesis gas high-temperature thermal reforming reactor (3) through the high-temperature resistant gas nozzle (10); Step 3: The raw synthesis gas preheated by the heat exchanger (2) enters the synthesis gas high-temperature thermal reforming reactor (3) through the nozzle annular gap channel (25) of the high-temperature resistant gas nozzle (10), and is fully mixed with the gasifying agent flowing in from the nozzle inner channel (24) at the outlet of the high-temperature resistant gas nozzle (10); then, partial combustion and high-temperature reforming reactions occur inside the synthesis gas high-temperature thermal reforming reactor (3), converting methane into CO and H2, and the reformed gas generated by the reaction is discharged from the high-temperature reformed gas outlet (11) at the bottom of the reactor; Step 4: The high-temperature reformed gas at the outlet of the synthesis gas high-temperature thermal reforming reactor (3) enters the radiation boiler (4) from the radiation boiler air inlet (12) to recover waste heat and is output from the radiation boiler air outlet (13); the temperature of the reformed gas is reduced from 1100° C. to 1350° C. at the inlet of the radiation boiler (4) to 750° C. to 850° C. at the outlet; high-pressure water enters the radiation boiler (4) from the high-pressure water inlet (22), and the by-product high-pressure saturated steam is discharged from the high-pressure steam outlet (23); Step 5: The reformed gas from the radiation boiler (4) enters the heat exchanger (2) through the reformed gas inlet (14) for further heat recovery, exchanges heat with the gas at the outlet of the crude synthesis gas scrubber (1), and is then discharged through the reformed gas outlet (15); after the waste heat is recovered, the temperature of the reformed gas at the outlet of the radiation boiler (4) is reduced from 750° C. to 850° C. at the inlet of the heat exchanger (2) to 150° C. to 250° C. at the outlet; Step 6: The reformed gas cooled by the heat exchanger (2) enters the reformed gas water washing tower (5) from the reformed gas water washing tower air inlet (16) for washing and is cooled by high-pressure cooling water; its temperature is further reduced to 30°C to 60°C to obtain synthesis gas for methanol synthesis, and then discharged from the reformed gas water washing tower air outlet (17).

7. The high temperature thermal reforming method of biomass gasification crude synthesis gas according to claim 6, characterized in that: The crude synthesis gas entering the crude synthesis gas water washing tower (1) has a water content of 10% to 60%, a methane content of 5% to 15%, a CO2 content of 20% to 45%, and a tar content of less than 10 g / Nm 3 ; The temperature is 150℃~250℃.

8. A high temperature thermal reforming system and method for raw synthesis gas from biomass gasification according to claim 6, characterized in that: The reaction temperature of the synthesis gas high temperature thermal reforming reactor (3) is 1100°C to 1350°C, and the pressure is 0.1 to 4 MPa.

9. The high temperature thermal reforming method of biomass gasification crude synthesis gas according to claim 6, characterized in that: The gasifying agent is a mixed gas of O2 / water vapor or O2 / CO2.

10. The high temperature thermal reforming method of biomass gasification crude synthesis gas according to claim 6, characterized in that: The molar ratio of O2 contained in the gasifying agent to the crude synthesis gas is 0.10 to 0.35.

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