CN111073711A - Low-tar biomass gasification method and system - Google Patents

Low-tar biomass gasification method and system Download PDF

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Publication number
CN111073711A
CN111073711A CN201911214561.0A CN201911214561A CN111073711A CN 111073711 A CN111073711 A CN 111073711A CN 201911214561 A CN201911214561 A CN 201911214561A CN 111073711 A CN111073711 A CN 111073711A
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Prior art keywords
fuel gas
temperature
gasification
heat exchanger
tar
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CN201911214561.0A
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Chinese (zh)
Inventor
刘华财
黄艳琴
袁洪友
颜毅
李劲松
田成来
余梦
胡文博
阴秀丽
吴创之
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State Grid Hubei Comprehensive Energy Service Co ltd
Wuhan Energy Efficiency Evaluation Co Ltd Of State Grid Electric Power Research Institute
Guangzhou Institute of Energy Conversion of CAS
State Grid Hubei Electric Power Co Ltd
Original Assignee
State Grid Hubei Comprehensive Energy Service Co ltd
Wuhan Energy Efficiency Evaluation Co Ltd Of State Grid Electric Power Research Institute
Guangzhou Institute of Energy Conversion of CAS
State Grid Hubei Electric Power Co Ltd
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Priority to CN201911214561.0A priority Critical patent/CN111073711A/en
Publication of CN111073711A publication Critical patent/CN111073711A/en
Pending legal-status Critical Current

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    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10J—PRODUCTION OF PRODUCER GAS, WATER-GAS, SYNTHESIS GAS FROM SOLID CARBONACEOUS MATERIAL, OR MIXTURES CONTAINING THESE GASES; CARBURETTING AIR OR OTHER GASES
    • C10J3/00—Production of combustible gases containing carbon monoxide from solid carbonaceous fuels
    • C10J3/72—Other features
    • C10J3/82—Gas withdrawal means
    • C10J3/84—Gas withdrawal means with means for removing dust or tar from the gas
    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10J—PRODUCTION OF PRODUCER GAS, WATER-GAS, SYNTHESIS GAS FROM SOLID CARBONACEOUS MATERIAL, OR MIXTURES CONTAINING THESE GASES; CARBURETTING AIR OR OTHER GASES
    • C10J3/00—Production of combustible gases containing carbon monoxide from solid carbonaceous fuels
    • C10J3/72—Other features
    • C10J3/82—Gas withdrawal means
    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10J—PRODUCTION OF PRODUCER GAS, WATER-GAS, SYNTHESIS GAS FROM SOLID CARBONACEOUS MATERIAL, OR MIXTURES CONTAINING THESE GASES; CARBURETTING AIR OR OTHER GASES
    • C10J2300/00—Details of gasification processes
    • C10J2300/09—Details of the feed, e.g. feeding of spent catalyst, inert gas or halogens
    • C10J2300/0903—Feed preparation
    • C10J2300/0909—Drying
    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10J—PRODUCTION OF PRODUCER GAS, WATER-GAS, SYNTHESIS GAS FROM SOLID CARBONACEOUS MATERIAL, OR MIXTURES CONTAINING THESE GASES; CARBURETTING AIR OR OTHER GASES
    • C10J2300/00—Details of gasification processes
    • C10J2300/09—Details of the feed, e.g. feeding of spent catalyst, inert gas or halogens
    • C10J2300/0913—Carbonaceous raw material
    • C10J2300/0916—Biomass
    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10J—PRODUCTION OF PRODUCER GAS, WATER-GAS, SYNTHESIS GAS FROM SOLID CARBONACEOUS MATERIAL, OR MIXTURES CONTAINING THESE GASES; CARBURETTING AIR OR OTHER GASES
    • C10J2300/00—Details of gasification processes
    • C10J2300/16—Integration of gasification processes with another plant or parts within the plant
    • C10J2300/1603—Integration of gasification processes with another plant or parts within the plant with gas treatment
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P20/00—Technologies relating to chemical industry
    • Y02P20/10—Process efficiency

Abstract

The invention discloses a low-tar biomass gasification method, which is characterized by comprising the following steps: (1) cooling tar-containing high-temperature fuel gas discharged from a high-temperature fuel gas outlet of the gasification furnace in a heat exchanger to obtain medium-temperature fuel gas; (2) the medium-temperature fuel gas from the outlet of the heat exchanger enters the lower part of the material bed, the temperature is reduced after the medium-temperature fuel gas upwards passes through the biomass raw material layer, and the low-temperature fuel gas is discharged from the upper part of the material bed; (3) drying the biomass raw material in the material bed by using fuel gas and then feeding the dried biomass raw material into a gasification furnace; one part of gasifying agent enters the heat exchanger, is preheated and then enters the gasification furnace together with the other part of gasifying agent, and reacts with the biomass to generate high-temperature fuel gas. The invention utilizes the low-temperature condensation characteristic of tar, and the gas passes through the heat exchanger and the material bed, so that the gasifying agent and the biomass raw material are preheated, and the tar is condensed and adsorbed on the biomass raw material, thereby reducing the tar content of the gas to the maximum extent and recovering the sensible heat and tar energy of the gas.

Description

Low-tar biomass gasification method and system
Technical Field
The invention relates to the technical field of biomass thermochemical conversion, in particular to a low-tar biomass gasification method and system.
Background
Biomass gasification is the conversion of solid biomass fuel into a fuel gas with the main combustible components hydrogen, carbon monoxide and methane. The fuel gas obtained by gasifying the biomass can be used for generating electricity, supplying heat or synthesizing liquid fuel, can replace fossil fuel such as coal, fuel oil and natural gas, and has wide application prospect.
The goal of biomass gasification is to obtain as much combustible gas product as possible, but tar is an inevitable by-product in the gasification process. Tar is condensed into viscous liquid which is attached to pipelines and downstream equipment, thus threatening the safe operation of the equipment; the tar is combined with dust in the condensation process and accumulated in the pipeline, and the pipeline is blocked when the tar is serious. The tar problem is the bottleneck limiting the popularization and application of the gasification technology. The low tar gasification technology can greatly reduce the difficulty and cost of gas purification and improve the applicability and the economical efficiency of biomass gasification. In the updraft type gasification furnace, the product in the pyrolysis zone upwards passes through the drying zone and then is discharged, heavy components in tar can be intercepted in a biomass raw material layer, but the gas tar content of the updraft type gasification furnace is very high, most of the gas tar is primary tar and secondary tar, the condensation temperature is relatively low, and the condensation interception effect in the tar furnace is not good; in the downdraft gasifier, the pyrolysis zone product passes through a high-temperature oxidation zone and a reduction zone, most of tar is cracked, and the fuel gas has low tar content but contains more polycyclic aromatic hydrocarbons and other heavy components which are difficult to crack.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provide a low-tar biomass gasification method and system capable of simply and effectively reducing tar in fuel gas.
The invention is realized by the following technical scheme: a low tar biomass gasification method comprises the following steps:
(1) cooling tar-containing high-temperature fuel gas discharged from a high-temperature fuel gas outlet of the gasification furnace in a heat exchanger to obtain medium-temperature fuel gas;
(2) the medium-temperature fuel gas from the outlet of the heat exchanger enters the lower part of the material bed, the temperature is reduced after the medium-temperature fuel gas upwards passes through the biomass raw material layer, and the low-temperature fuel gas is discharged from the upper part of the material bed;
(3) drying the biomass raw material in the material bed by using fuel gas and then feeding the dried biomass raw material into a gasification furnace; one part of gasifying agent enters the heat exchanger, is preheated and then enters the gasification furnace together with the other part of gasifying agent, and reacts with the biomass to generate high-temperature fuel gas.
The low-tar biomass gasification method provided by the invention has the advantages that the sensible heat of the fuel gas is fully utilized, the gasification agent is preheated, and the biomass raw material is dried, so that the tar content is reduced, the tar energy is recovered, and the method is simple, effective, energy-saving and environment-friendly; after the fuel gas is cooled, adsorbed and filtered by the biomass raw material layer, most of tar is removed.
Preferably, the gasification furnace in the step (1) is a downdraft fixed bed gasification furnace with a throat. The temperature of high-temperature fuel gas at the outlet of the downdraft fixed bed gasification furnace can reach 800-1000 ℃, and a gasifying agent entering the heat exchanger can be preheated to a higher temperature and then is introduced into the throat part, so that the throat temperature can be increased, the tar cracking in the furnace can be enhanced, and the tar content of the high-temperature fuel gas at the outlet of the gasification furnace can be further reduced.
Preferably, the temperature of the medium-temperature fuel gas in the step (1) is higher than 300 ℃ so as to ensure that tar cannot be condensed in the heat exchanger.
Preferably, in the step (2), the temperature range of the low-temperature fuel gas at the outlet of the material bed is 70-130 ℃, so that tar is condensed and adsorbed in the biomass raw material layer, and water vapor is taken away.
Preferably, the gasifying agent in the step (3) is at least one of air, water vapor and oxygen.
Preferably, the feeding and discharging of the material bed in the step (3) adopt an airtight device to ensure that fuel gas cannot leak; in the step (2), the material bed is a fixed bed or a roller dryer, and the temperature of fuel gas is reduced to 70-130 ℃.
And (4) regulating the flow of the gasifying agent entering the heat exchanger according to the temperature reduction condition of the fuel gas in the step (3) so as to ensure that tar is not condensed in the heat exchanger. The invention reduces the temperature of the fuel gas and recovers heat through the heat exchanger, and then utilizes the biomass raw material layer to cool and adsorb tar in the fuel gas, so as to finally reduce the temperature of the fuel gas to about 100 ℃, thereby reducing the tar content of the fuel gas, especially the content of heavy tar components.
The invention also protects a low tar biomass gasification system for realizing the low tar biomass gasification method, which comprises a gasification furnace, a heat exchanger and a material bed; the gasifier is provided with a high-temperature gas outlet, the high-temperature gas outlet is connected with the heat exchanger through a high-temperature gas pipeline, and the heat exchanger is connected with the material bed through a medium-temperature gas pipeline; a gasification agent pipeline is arranged between the heat exchanger and the gasification furnace, and the outlet of the material bed is connected with the gasification furnace through an airtight feeding device. The medium-temperature fuel gas after being cooled in the heat exchanger enters the material bed through a medium-temperature fuel gas pipeline, and the preheated gasifying agent in the heat exchanger enters the gasification furnace; the biomass raw material at the outlet of the material bed enters the gasification furnace through the airtight feeding device.
In the invention, the gasification furnace is used for reacting the biomass with the gasification agent after heat exchange with the high-temperature fuel gas to obtain the high-temperature fuel gas; the heat exchanger is used for recovering the heat energy of the high-temperature fuel gas and preheating the gasifying agent, and the gasifying agent can improve the gasification reaction temperature in the gasifier and reduce the tar content in the high-temperature fuel gas at the outlet of the gasifier after being preheated; the material bed is used for condensing, adsorbing and intercepting tar in the fuel gas by utilizing the biomass material layer, and recovering fuel gas heat energy and tar energy while drying the raw materials.
Preferably, the gasification furnace is a downdraft fixed bed gasification furnace with a throat, and the high-temperature fuel gas has low tar content and is mostly heavy components such as polycyclic aromatic hydrocarbon with high condensation temperature, and is easier to be intercepted by the material bed; the temperature of high-temperature fuel gas at the outlet of the downdraft fixed bed gasification furnace can reach 800-1000 ℃, and a gasifying agent entering the heat exchanger can be preheated to a higher temperature and then is introduced into the throat part, so that the throat temperature can be increased, the tar cracking in the furnace can be enhanced, and the tar content of the high-temperature fuel gas at the outlet of the gasification furnace can be further reduced.
The gasification agent pipeline is divided into a first gasification agent pipeline and a second gasification agent pipeline, and the first gasification agent pipeline is communicated with the bottom of the gasification furnace; one end of the heat exchanger is provided with a gasifying agent inlet, the other end of the heat exchanger is provided with a gasifying agent outlet, the second gasifying agent pipeline is communicated with the gasifying agent outlet of the heat exchanger and the gasification furnace, and the gasifying agent passing through the heat exchanger enters the gasification furnace through the second gasifying agent pipeline through the gasifying agent outlet. The gasifying agent is air, water vapor or a mixture of air and water vapor, taking the air as an example, the inlet air of the gasification furnace is divided into two paths, one path is directly fed into the gasification furnace, the other path enters the gasification furnace through the heat exchanger, and the air quantity entering the heat exchanger is adjusted according to the temperature of fuel gas so as to ensure that tar is not condensed in the heat exchanger.
Preferably, the airtight feeding device is arranged at the bottom of the material bed.
Preferably, under the condition that the humidity of the biomass raw material is high, the material bed is a roller dryer, so that the drying effect of the biomass raw material and the temperature of fuel gas are reduced to about 100 ℃.
Preferably, the heat exchanger is a shell-and-tube type, wherein the gas is on the tube side, and the air is on the shell side, so that dust and tar which are possibly adsorbed in the heat exchanger can be conveniently removed.
Preferably, the material bed adopts an airtight feeding and discharging device to ensure that fuel gas cannot leak.
Compared with the prior art, the invention has the advantages that: the invention fully utilizes the sensible heat of the fuel gas, preheats the gasifying agent, dries the biomass raw material, reduces the tar content, recovers the tar energy, is simple and effective, and is energy-saving and environment-friendly. Besides being used for biomass gasification, the gasification furnace can also be used for gasification and utilization of solid fuels or solid wastes such as coal, petroleum coke and the like.
Drawings
FIG. 1 is a schematic diagram of a system process according to an embodiment of the present invention.
The reference numerals in the drawings mean: 1. a gasification furnace; 2. high-temperature fuel gas; 3. a heat exchanger; 4. a gasifying agent; 5. medium temperature gas; 6. a material bed; 7. a biomass feedstock; 8. low-temperature fuel gas; 9. drying the biomass raw material; 10. a preheated gasifying agent; 11. a laryngeal opening.
Detailed Description
The present invention will be described in further detail with reference to the accompanying drawings and detailed description.
Examples
Referring to fig. 1, a low tar biomass gasification method includes the following steps:
(1) the tar-containing high-temperature fuel gas 2 from the high-temperature fuel gas 2 outlet of the gasification furnace 1 enters a heat exchanger 3 to be cooled, and medium-temperature fuel gas 5 is obtained;
(2) the medium-temperature fuel gas 5 from the outlet of the heat exchanger 3 enters the lower part of the material bed 6, the temperature is reduced after passing through the 7 layers of biomass raw materials upwards, the low-temperature fuel gas 8 is discharged from the upper part of the material bed 6, and the dried biomass raw materials 9 are discharged from the lower part of the material bed 6;
(3) the biomass raw material 7 in the material bed 6 is dried by fuel gas and then enters the gasification furnace 1; one part of the gasifying agent 4 enters the heat exchanger 3, the preheated gasifying agent 10 and the other part of the gasifying agent 4 which is not preheated enter a throat 11 of the gasification furnace 1 together, and react with the dried biomass raw material 9 to generate high-temperature fuel gas 2.
The height of the furnace body of the material bed 6 and the thickness of the 7 layers of the biomass raw materials in the furnace are 2-6 m, the retention time of the fuel gas in the 7 layers of the biomass raw materials is prolonged, tar in the fuel gas is cooled and adsorbed by utilizing the 7 layers of the biomass raw materials, the temperature of the low-temperature fuel gas 8 is controlled to be about 100 ℃, and the tar content, particularly the content of heavy tar components, in the low-temperature fuel gas 8 is reduced.
The low-tar biomass gasification method provided by the invention has the advantages that the sensible heat of the fuel gas is fully utilized, the gasification agent 4 is preheated, and the biomass raw material 7 is dried, so that the tar content is reduced, the tar energy is recovered, and the method is simple, effective, energy-saving and environment-friendly; after the medium-temperature fuel gas 5 is cooled, adsorbed and filtered by the biomass raw material 7 layers, the tar content in the high-temperature fuel gas 2 is lower and is mostly heavy components such as polycyclic aromatic hydrocarbon with higher condensation temperature, and the heavy components are easier to be intercepted by the biomass raw material 7 layers in the material bed 6, and most of the tar in the fuel gas is removed.
Preferably, the gasification furnace 1 is a downdraft fixed bed gasification furnace with a throat 11. The temperature of the high-temperature fuel gas 2 at the outlet of the downdraft fixed bed gasification furnace 1 can reach 800-1000 ℃, the gasifying agent 4 entering the heat exchanger 3 can be preheated to a higher temperature and then is introduced into the throat 11, the temperature of the throat 11 can be increased, the tar cracking in the furnace can be enhanced, and the tar content of the high-temperature fuel gas 2 at the outlet of the gasification furnace 1 can be further reduced.
Preferably, the temperature of the medium temperature combustion gas 5 is higher than 300 ℃ to ensure that tar does not condense in the heat exchanger 3.
Preferably, the temperature range of the low-temperature fuel gas 8 at the outlet of the material bed 6 is 70-130 ℃, so that tar is condensed and adsorbed in the layer 7 of the biomass raw material, and water vapor is taken away.
Preferably, the gasifying agent 4 is at least one of air, water vapor and oxygen. The gasifying agent 4 is one of the following gases: air, water vapor, air/water vapor mixtures, oxygen, air/oxygen mixtures, water vapor/oxygen mixtures, air/water vapor/oxygen mixtures. In this embodiment, the gasifying agent 4 is preferably air.
Preferably, the material bed 6 adopts an airtight device for feeding and discharging so as to ensure that fuel gas cannot leak; the material bed 6 is a fixed bed or a roller dryer, and the temperature of fuel gas is ensured to be reduced to 70-130 ℃.
The flow of the gasifying agent 4 entering the heat exchanger 3 is adjusted according to the temperature reduction condition of the fuel gas so as to ensure that the tar is not condensed in the heat exchanger 3. According to the invention, the temperature of the fuel gas is reduced and the heat is recovered through the heat exchanger 3, and then the 7 layers of biomass raw materials are utilized to cool and adsorb tar in the fuel gas, so that the temperature of the fuel gas is finally reduced to about 100 ℃, and the tar content of the fuel gas, especially the content of heavy tar components, is reduced.
Referring to fig. 1, the invention also protects a low tar biomass gasification system for implementing the low tar biomass gasification method, comprising a gasification furnace 1, a heat exchanger 3 and a material bed 6; the gasification furnace 1 is provided with a high-temperature fuel gas 2 outlet, the high-temperature fuel gas 2 outlet is connected with a heat exchanger 3 through a high-temperature fuel gas 2 pipeline, and the heat exchanger 3 is connected with a material bed 6 through a medium-temperature fuel gas 5 pipeline; a gasifying agent pipeline is arranged between the heat exchanger 3 and the gasification furnace 1, and the outlet of the material bed 6 is connected with the gasification furnace 1 through an airtight feeding device. The cooled medium-temperature fuel gas 5 in the heat exchanger 3 enters the material bed 6 through a medium-temperature fuel gas 5 pipeline, and the preheated gasifying agent 10 in the heat exchanger 3 enters the gasification furnace 1; the dried biomass raw material 9 at the outlet of the material bed 6 enters the gasification furnace 1 through an airtight feeding device.
In the invention, the gasification furnace 1 is used for reacting the biomass with the gasification agent 4 after heat exchange with the high-temperature fuel gas 2 to obtain the high-temperature fuel gas 2; the heat exchanger 3 is used for recovering heat energy of the high-temperature fuel gas 2 and preheating the gasifying agent 4, and the gasifying agent 4 can improve the gasification reaction temperature in the gasifier after being preheated and reduce the tar content in the high-temperature fuel gas 2 at the outlet of the gasifier 1; the material bed 6 is used for condensing, adsorbing and intercepting tar in the fuel gas by utilizing the biomass material layer, and recovering fuel gas heat energy and tar energy while drying the raw materials.
Preferably, the gasification furnace 1 is a downdraft fixed bed gasification furnace 1 with a throat 11, and the high-temperature fuel gas 2 is low in tar content and mostly contains heavy components such as polycyclic aromatic hydrocarbon with high condensation temperature, and is easier to be intercepted by the material bed 6; the temperature of the high-temperature fuel gas 2 at the outlet of the downdraft fixed bed gasification furnace 1 can reach 800-1000 ℃, the gasifying agent 4 entering the heat exchanger 3 can be preheated to a higher temperature and then is introduced into the throat 11, the temperature of the throat 11 can be increased, the tar cracking in the furnace can be enhanced, and the tar content of the high-temperature fuel gas 2 at the outlet of the gasification furnace 1 can be further reduced.
The gasification agent pipeline is divided into a first gasification agent pipeline and a second gasification agent pipeline, and the first gasification agent pipeline is communicated with the bottom of the gasification furnace 1; one end of the heat exchanger 3 is provided with a gasifying agent inlet, the other end of the heat exchanger is provided with a gasifying agent outlet, a second gasifying agent pipeline is communicated with the gasifying agent outlet of the heat exchanger 3 and the gasification furnace 1, and the gasifying agent 4 passing through the heat exchanger 3 enters the gasification furnace 1 through the second gasifying agent pipeline through the gasifying agent outlet. The gasifying agent 4 is air, water vapor or a mixture of air and water vapor, taking the air as an example, the inlet air of the gasification furnace 1 is divided into two paths, one path is directly fed into the gasification furnace 1, the other path is fed into the gasification furnace 1 through the heat exchanger 3, and the air quantity fed into the heat exchanger 3 is adjusted according to the temperature of fuel gas so as to ensure that tar is not condensed in the heat exchanger 3.
Preferably, the gas-tight feeding device is arranged at the bottom of the material bed 6.
Preferably, under the condition that the humidity of the biomass raw material 7 is high, the material bed 6 is a roller dryer, so that the drying effect of the biomass raw material 7 and the temperature of fuel gas are reduced to about 100 ℃.
Preferably, the heat exchanger 3 is shell and tube, with gas on the tube side and air on the shell side, to facilitate the removal of dust and tars that may be adsorbed in the heat exchanger 3.
Preferably, the material bed 6 employs airtight feeding and discharging devices to ensure that the fuel gas does not leak.
Referring to fig. 1, a low tar biomass gasification system includes a gasification furnace 1, a heat exchanger 3 and a material bed 6. The gasification furnace 1 is a downdraft type fixing with a throat 11The dried biomass raw material 9 enters the bed gasification furnace 1 from the top, the gasification agent 4 and the preheated gasification agent 10 enter from the throat 11, the temperature of the high-temperature fuel gas 2 is 800-1000 ℃, and the tar content can be as low as 100mg/m3Left and right; the heat exchanger 3 is a shell-and-tube type, the high-temperature fuel gas 2 enters the heat exchanger 3 from the tube side, and the medium-temperature fuel gas 5 is obtained after cooling; a part of the gasifying agent 4 enters the heat exchanger 3 from the shell side to obtain a preheated gasifying agent 10, and the temperature of the medium-temperature fuel gas 5 is kept above 300 ℃ to prevent tar from condensing; biomass raw materials 7 enter from the upper part of a material bed 6, and medium-temperature fuel gas 5 enters from the lower part of the material bed 6 and passes through a biomass raw material 7 layer upwards to obtain low-temperature fuel gas 8 and dried biomass raw materials 9; the low-temperature fuel gas 8 is led out from the upper part of the material bed 6 at the temperature of about 100 ℃, and tar is condensed and adsorbed in the layer 7 of the biomass raw material.
The process flow of the tar purification treatment in this example is: the gasification agent 4 and the preheated gasification agent 10 enter the gasification furnace 1 from a throat 11 of the gasification furnace 1, and react with the dried biomass raw material 9 to generate high-temperature fuel gas 2, wherein the outlet temperature of the high-temperature fuel gas 2 is 800-1000 ℃; the high-temperature fuel gas 2 enters a heat exchanger 3 and a gasifying agent 4 for heat exchange to obtain medium-temperature fuel gas 5 and a preheated gasifying agent 10; the biomass raw material 7 enters from the upper part of the material bed 6, the medium-temperature fuel gas 5 enters from the lower part of the material bed 6 and passes through the biomass raw material 7 layer upwards, and the low-temperature fuel gas 8 and the dried biomass raw material 9 are obtained.
Comparative example 1
Comparative example 1 differs from the examples in that: the pyrolysis zone product of the gasification furnace 1 passes through a high-temperature oxidation zone and a reduction zone, most of tar is cracked, and the tar content of high-temperature fuel gas 2 is generally lower than 1g/Nm3But contains heavy components such as polycyclic aromatic hydrocarbon which are difficult to crack; the gasifying agent 4 (air) directly enters the gasification furnace 1, the tar waste liquid is treated by conventional means such as downstream oxidation digestion, biochemical treatment and the like, the initial investment is large, the operation cost is high, and the sensible heat of the fuel gas and the total tar energy are lost.
Compared with the comparative example 1, the embodiment further reduces the tar content of the fuel gas, recovers the sensible heat of the fuel gas and most tar energy, improves the gasification efficiency by about 5 percent, has simple process and system, reduces the purification difficulty of the downstream tar and greatly reduces the cost.
The above detailed description is specific to possible embodiments of the present invention, and the embodiments are not intended to limit the scope of the present invention, and all equivalent implementations or modifications that do not depart from the scope of the present invention are intended to be included within the scope of the present invention.

Claims (9)

1. A low tar biomass gasification method is characterized by comprising the following steps:
(1) cooling tar-containing high-temperature fuel gas discharged from a high-temperature fuel gas outlet of the gasification furnace in a heat exchanger to obtain medium-temperature fuel gas;
(2) the medium-temperature fuel gas from the outlet of the heat exchanger enters the lower part of the material bed, the temperature is reduced after the medium-temperature fuel gas upwards passes through the biomass raw material layer, and the low-temperature fuel gas is discharged from the upper part of the material bed;
(3) drying the biomass raw material in the material bed by using fuel gas and then feeding the dried biomass raw material into a gasification furnace; one part of gasifying agent enters the heat exchanger, is preheated and then enters the gasification furnace together with the other part of gasifying agent, and reacts with the biomass to generate high-temperature fuel gas.
2. The low tar biomass gasification method according to claim 1, characterized in that: the gasification furnace is a downdraft fixed bed gasification furnace with a throat.
3. The low tar biomass gasification method according to claim 1, characterized in that: the temperature of the medium-temperature fuel gas is higher than 300 ℃.
4. The low tar biomass gasification method according to claim 1, characterized in that: the temperature range of the low-temperature fuel gas at the outlet of the material bed is 70-130 ℃.
5. The low tar biomass gasification method according to claim 1, characterized in that: the gasifying agent is at least one of air, water vapor and oxygen.
6. The low tar biomass gasification method according to claim 1, characterized in that: and the feeding and discharging of the material bed adopt an airtight device.
7. A low tar biomass gasification system for realizing the low tar biomass gasification method according to claim 1, characterized in that: comprises a gasification furnace, a heat exchanger and a material bed; the gasifier is provided with a high-temperature gas outlet, the high-temperature gas outlet is connected with the heat exchanger through a high-temperature gas pipeline, and the heat exchanger is connected with the material bed through a medium-temperature gas pipeline; a gasification agent pipeline is arranged between the heat exchanger and the gasification furnace, and the outlet of the material bed is connected with the gasification furnace through an airtight feeding device.
8. The low tar biomass gasification system of claim 7, wherein: the gasification agent pipeline is divided into a first gasification agent pipeline and a second gasification agent pipeline, and the first gasification agent pipeline is communicated with the bottom of the gasification furnace; one end of the heat exchanger is provided with a gasifying agent inlet, the other end of the heat exchanger is provided with a gasifying agent outlet, and the second gasifying agent pipeline is communicated with the gasifying agent outlet of the heat exchanger and the gasification furnace.
9. The low tar biomass gasification system of claim 7, wherein: the material bed is a fixed bed or a roller dryer.
CN201911214561.0A 2019-12-02 2019-12-02 Low-tar biomass gasification method and system Pending CN111073711A (en)

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Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN2677376Y (en) * 2004-01-16 2005-02-09 中国科学院广州能源研究所 Down-draft gasification furnace
CN101012384A (en) * 2007-01-31 2007-08-08 华东理工大学 Method and device for preparing combustion gas by gasifying biomass

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN2677376Y (en) * 2004-01-16 2005-02-09 中国科学院广州能源研究所 Down-draft gasification furnace
CN101012384A (en) * 2007-01-31 2007-08-08 华东理工大学 Method and device for preparing combustion gas by gasifying biomass

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
邱树林: "《换热器 原理·结构·设计》", 31 July 1990, 上海交通大学出版社 *

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Application publication date: 20200428