阅读说明：本技术 一种生物质熔融气化的方法和系统 (Method and system for biomass melt gasification ) 是由 陈钢 唐凤金 程正中 陈延林 邢学想 杨巍巍 黄凯 杨钦 李清 魏喆 黄俊超 于 2020-11-20 设计创作，主要内容包括：本发明公开了一种生物质熔融气化的方法和系统。将生物质输入并压缩成块,升温、干燥、热解后得到预处理后的生物质和热解气；预处理后的生物质和热解气在高温下熔融气化,生成高温熔融物和气化气。本技术开发用于处理各种城市垃圾、工业垃圾、危险废物、污泥等废物,变废为宝,具有广阔的市场前景。(The invention discloses a method and a system for biomass melt gasification. Inputting and compressing biomass into blocks, heating, drying and pyrolyzing the blocks to obtain pretreated biomass and pyrolysis gas; and melting and gasifying the pretreated biomass and the pyrolysis gas at high temperature to generate high-temperature melt and gasified gas. The technology is developed and used for treating various municipal waste, industrial waste, dangerous waste, sludge and other wastes, changes waste into valuable, and has wide market prospect.)

1. A method of biomass melt gasification, characterized by the steps of:

step 1: inputting and compressing biomass into blocks;

step 2: heating, drying and pyrolyzing the compressed biomass blocks to obtain pretreated biomass and pyrolysis gas;

and step 3: melting and gasifying the pretreated biomass and pyrolysis gas at high temperature under the condition of pure oxygen or oxygen enrichment to generate high-temperature melt and gasification gas; carrying out homogeneous flow on the high-temperature melt to obtain a molten glass body with uniform properties and a stable structure;

and 4, step 4: will gasification gas chills, washing back, washes and removes soluble harmful substance, flying dust impurity and obtains the purified gas, the volume content that the purified gas is constituteed is: CO content of 10-45%, H₂Content 10% -50%, CH₄0-30% of CO₂0 to 15 percent of N₂The content is 5-30%.

2. The method of biomass melt gasification according to claim 1, characterized in that: the compression and blocking in the step 1 adopt a multi-stage, high-pressure, continuous compression and molding and continuous discharging biomass compression molding method, the length-width ratio of the section of a compression cavity is 1.5: 1-4: 1, the ratio of the compressed thickness of a compression block to the width of the section of the compression cavity is 0.2-1.2, the compression molding pressure of the biomass is 2-16 MPa, the pre-compression pressure-maintaining time is not less than 2 seconds, and the compression molding pressure-maintaining time is not less than 2 seconds; the biomass pre-compression pressure is 10% -50% of the compression molding pressure.

3. The method of biomass melt gasification according to claim 1, characterized in that: the temperature of the melting gasification in the step 3 is 1200-2000 ℃.

4. A system for the melt gasification of biomass according to any one of claims 1 to 3, characterized by comprising: the system comprises a feeding unit, a preheating unit, a gasification unit and a post-treatment unit;

wherein the feed unit is used to transport the biomass to the system and compress it into briquettes;

the preheating unit is used for preheating the compressed biomass;

the gasification unit is used for carrying out high-temperature melting gasification on the preheated biomass and the pyrolysis gas to generate a high-temperature melt and a gasification gas;

the post-treatment unit is used for chilling and washing the gasified gas to obtain purified gas, and discharging the high-temperature melt after the high-temperature melt flows uniformly.

5. The system for the melt gasification of biomass of claim 4, wherein: the feeding unit comprises a biomass feeding machine and a biomass compressor;

the biomass feeder is used for conveying biomass to a biomass compressor;

the biomass compressor is used for compressing biomass into blocks, and the length-width ratio of the section of the compression cavity is 1.5: 1-4: 1.

6. The system for the melt gasification of biomass of claim 4, wherein: the preheating unit comprises a raw material preheating device and preheating equipment; the raw material preheater is provided with a partition wall, hot flue gas generated by the preheating device passes through the partition wall to heat biomass passing through the raw material preheater, and the biomass compressed into blocks is heated, dried and pyrolyzed in the raw material preheater.

7. The system for the melt gasification of biomass of claim 6, wherein: the preheating equipment comprises a combustion hot blast stove and an air preheater, air enters the combustion hot blast stove after being heated by the air preheater to support combustion of fuel gas, and generated hot flue gas passes through the partition wall of the raw material preheating decomposer to heat the biomass raw material and the air.

8. The system for the melt gasification of biomass of claim 4, wherein: the gasification unit comprises a gasification furnace, and the preheated biomass is melted and gasified at high temperature in the gasification furnace to generate high-temperature melt and gasified gas; the gasification furnace is at least divided into three temperature zones: the temperature of the upper gas phase space is 900-1400 ℃, the temperature of the middle and lower biomass gasification areas is 1200-2000 ℃, and the temperature of the tail melt flowing area is 1400-2000 ℃; the operation pressure of the gasification furnace is-0.1 MPaG to 2.0 MPaG.

9. The system for the melt gasification of biomass of claim 4, wherein: the post-treatment unit comprises a mixed gas treatment unit and a high-temperature melt treatment unit which are respectively arranged at the top and the bottom of the gasification unit, the mixed gas treatment unit comprises a chilling tank and a washing tower which are sequentially connected with the gasification unit, and the high-temperature mixed gas leaves the gasification furnace from the top, enters the chilling tank for chilling and is sent to the washing tower for washing and purification; the high-temperature melt processing unit comprises a homogenizing channel, and the high-temperature melt flows in the homogenizing channel for a period of time and then is discharged out of the system to obtain a molten glass body with uniform properties and a stable structure.

10. The system for the melt gasification of biomass according to claim 9, characterized in that: the mixed gas treatment unit also comprises a water treatment system, the water treatment system is connected with the washing tower and the chilling tank, and washing water generated by the washing tower is treated by the water treatment system and then is circulated back to the chilling tank to be recycled as chilling liquid.

Technical Field

The invention belongs to the technical field of biomass gasification, and particularly relates to a method and a system for biomass melting gasification.

Background

The problem of accumulating waste biomass such as municipal solid waste, medical waste and municipal sludge is becoming more serious, and the methods for treating municipal solid waste, medical waste and municipal sludge at home and abroad nowadays generally include: sanitary landfill, direct burning, plasma gasification, etc.

The sanitary landfill not only occupies a large amount of land, but also contains a large amount of heavy metals and bacteria in the biomass such as the garbage, the sludge and the like, and can generate stink to cause serious pollution to water, soil and atmosphere. With the increasing of the production of biomass such as garbage and sludge year by year, the embarrassing situation that garbage and sludge can be buried and piled up without land has occurred in many places, and the environmental and ecological safety problems caused by garbage landfill pollution are very serious.

The direct incineration of biomass such as garbage, sludge and the like can realize biomass reduction, power generation can be carried out while the occupied land is reduced, and certain economic benefit is created. However, direct incineration also brings a series of problems: firstly, carcinogenic substances such as dioxin, furan and the like are easily generated due to low incineration temperature; secondly, the fly ash and the residue generated by incineration are rich in toxic and harmful heavy metal substances, which easily causes pollution to underground water sources; and thirdly, a large amount of smoke is generated by incineration, and the carbon emission is large.

The principle of the plasma gasification technology is that by utilizing the physical characteristics of plasma, the high-temperature plasma has high energy density, the neutral particle temperature is close to the electron temperature, and the reaction activity of various particles is high, the center temperature of a plasma torch for treating oily sludge waste generally can reach 30000 ℃, the edge temperature can also reach about 3000 ℃, when the high-temperature plasma impacts a treated object, the treated object is quickly gasified and decomposed, new substances are generated by recombination, and therefore the treated harmful substances are changed into harmless substances. However, the method has high energy consumption, short plasma moment service life, frequent equipment replacement and high treatment cost.

Therefore, the search and research for developing a new green and environment-friendly technology for treating biomass such as garbage, sludge and the like, and reducing and eliminating the problem of environmental pollution caused in the process of treating oily sludge as much as possible become a new subject in the field of treating biomass such as garbage, sludge and the like at present. Particularly, with the rapid development of economy and the increasing shortage of energy resources in recent years, the harmlessness, reduction and recycling of the treatment of biomass such as garbage, sludge and the like become a new development direction of the industry at present.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provide a method and a system for biomass melt gasification.

In order to achieve the purpose, the invention adopts the following technical scheme: a method of biomass melt gasification, characterized by the steps of:

step 1: inputting and compressing biomass into blocks;

step 2: heating, drying and pyrolyzing the compressed biomass blocks to obtain pretreated biomass and pyrolysis gas;

and step 3: melting and gasifying the pretreated biomass and pyrolysis gas at high temperature under the condition of pure oxygen or oxygen enrichment to generate high-temperature melt and gasification gas; carrying out homogeneous flow on the high-temperature melt to obtain a molten glass body with uniform properties and a stable structure;

and 4, step 4: will gasification gas chills, washing back, washes and removes soluble harmful substance, flying dust impurity and obtains the purified gas, the volume content that the purified gas is constituteed is: CO content of 10-45%, H₂Content 10% -50%, CH₄0-30% of CO₂0 to 15 percent of N₂The content is 5-30%.

Further, the compression block in the step 1 is formed by a multi-stage, high-pressure, continuous compression molding and continuous discharging biomass compression molding method, the length-width ratio of the section of a compression cavity is 1.5: 1-4: 1, the ratio of the thickness of the compressed block to the width of the section of the compression cavity is 0.2-1.2, the compression molding pressure of the biomass is 2-16 MPa, the pre-compression pressure-maintaining time is not less than 2 seconds, and the compression molding pressure-maintaining time is not less than 2 seconds; the biomass pre-compression pressure is 10% -50% of the compression molding pressure.

Further, the temperature of the melting gasification in the step 3 is 1200-2000 ℃.

A system for the melt gasification of biomass, comprising: the system comprises a feeding unit, a preheating unit, a gasification unit and a post-treatment unit;

wherein the feed unit is used to transport the biomass to the system and compress it into briquettes;

the preheating unit is used for preheating the compressed biomass;

the gasification unit is used for carrying out high-temperature melting gasification on the preheated biomass and the pyrolysis gas to generate a high-temperature melt and a gasification gas;

the post-treatment unit is used for chilling and washing the gasified gas to obtain purified gas, and discharging the high-temperature melt after the high-temperature melt flows uniformly.

Further, the feeding unit comprises a biomass feeding machine and a biomass compressor;

the biomass feeder is used for conveying biomass to a biomass compressor;

the biomass compressor is used for compressing biomass into blocks, and the length-width ratio of the section of the compression cavity is 1.5: 1-4: 1.

Further, the preheating unit comprises a raw material preheating decomposer and preheating equipment; the raw material preheater is provided with a partition wall, hot flue gas generated by the preheating device passes through the partition wall to heat biomass passing through the raw material preheater, and the biomass compressed into blocks is heated, dried and pyrolyzed in the raw material preheater.

Further, the preheating device comprises a combustion hot blast stove and an air preheater, air enters the combustion hot blast stove after being heated by the air preheater to support combustion of fuel gas, and generated hot flue gas passes through the partition wall of the raw material preheating decomposer to heat the biomass raw material and the air.

Further, the gasification unit comprises a gasification furnace, and the preheated biomass is melted and gasified at high temperature in the gasification furnace to generate high-temperature melt and gasified gas; the gasification furnace is at least divided into three temperature zones: the temperature of the upper gas phase space is 900-1400 ℃, the temperature of the middle and lower biomass gasification areas is 1200-2000 ℃, and the temperature of the tail melt flowing area is 1400-2000 ℃; the operation pressure of the gasification furnace is-0.1 MPaG to 2.0 MPaG.

Furthermore, the post-treatment unit comprises a mixed gas treatment unit and a high-temperature melt treatment unit which are respectively arranged at the top and the bottom of the gasification unit, the mixed gas treatment unit comprises a quenching tank and a washing tower which are sequentially connected with the gasification unit, and the high-temperature mixed gas leaves the gasification furnace from the top, enters the quenching tank for quenching, and is sent to the washing tower for washing and purification; the high-temperature melt processing unit comprises a homogenizing channel, and the high-temperature melt flows in the homogenizing channel for a period of time and then is discharged out of the system to obtain a molten glass body with uniform properties and a stable structure.

Furthermore, the mixed gas treatment unit also comprises a water treatment system, the water treatment system is connected with the washing tower and the chilling tank, and washing water generated by the washing tower is treated by the water treatment system and then is circulated back to the chilling tank to be recycled as chilling liquid.

Biomass for the present application includes, but is not limited to, garbage, medical waste, general solid waste, corn stover, sludge, fly ash, and the like.

Has the advantages that:

(1) the method provided by the invention utilizes high temperature, carries out conversion treatment on biomass such as garbage or sludge and the like under the condition of pure oxygen or oxygen enrichment, outputs the biomass in the form of high-temperature gas and non-leachable slag, is green and environment-friendly in the treatment process, does not discharge wastewater and waste slag, and has dioxin discharge far lower than the strictest environment-friendly discharge standard of European Union and the like.

(2) From an ecological perspective, biomass such as garbage or sludge is a source of pollution, but from a resource perspective, garbage is an increasing resource on earth. For example, the method provided by the invention can be used for treating garbage and then generating power, if China can classify the garbage and sufficiently and effectively use the garbage for power generation, 4000-6000 million coal resources can be saved every year.

(3) Biomass such as garbage or sludge is melted and gasified to generate a certain amount of synthesis gas, vitreous body slag and heat energy, and the comprehensive utilization can effectively reduce the energy consumption of the biomass melting and gasifying device or form additional value.

The technology is developed and used for treating various municipal waste, industrial waste, dangerous waste, sludge and other wastes, changes waste into valuable, and has wide market prospect.

Drawings

Fig. 1 is a schematic configuration diagram of a biomass melt gasification system according to example 1.

Detailed Description

In order to make the technical solutions better understood by those skilled in the art, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only partial embodiments of the present application, but not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

It should be noted that the terms "comprises" and "comprising," and any variations thereof, in the description and claims of this application and the above-described drawings, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.

A system for biomass melt gasification as shown in fig. 1, comprising: the device comprises a feeding unit, a preheating unit, a gasification unit and a post-treatment unit.

Wherein the feed unit is used to transport the biomass to the system and compress it into briquettes. The feeding unit comprises a biomass feeder 1 and a biomass compressor 2. The biomass feeder is used for conveying biomass to the biomass compressor; the biomass compressor is used for compressing biomass into briquettes. The biomass is compressed into blocks in a biomass compressor by adopting a multi-stage, high-pressure, continuous compression molding and continuous discharging method, so that irregular biomass bulk materials can be compressed and molded under reasonable hydraulic conditions, and the internal gaps of the compressed blocks are reduced to the greatest extent; mainly used as a front-end compression feeding process for biomass advanced treatment such as anaerobic degassing carbonization and the like. The length-width ratio of the section of the compression cavity is 1.5: 1-4: 1, the ratio of the compressed thickness of the compressed package to the width of the section of the compression cavity is 0.2-1.2, the pressure of biomass compression molding is 2-16 MPa, too small pressure is not beneficial to bulk cargo compression molding, and the package is easy to loosen; too high pressure can cause excessive expansion of the discharged package blocks, and easily cause blockage of downstream channels. The pre-compression pressure maintaining time is not less than 2 seconds, and the compression molding pressure maintaining time is not less than 2 seconds; the biomass pre-compression pressure is 10% -50% of the compression molding pressure.

The preheating unit is used for preheating the compressed biomass. The preheating unit comprises a raw material preheating decomposer 3 and preheating equipment. The raw material preheater is provided with the next door, and preheating equipment includes burning hot-blast furnace 5 and air heater 6, and the air gets into burning hot-blast furnace after the air heater heating and supports the fuel gas burning, and the hot flue gas of production passes through raw materials preheating decomposer next door in order to heat biomass raw materials and air. The biomass compressed into blocks is heated, dried and pyrolyzed in a raw material pre-pyrolysis device.

The gasification unit comprises a gasification furnace 4, the preheated biomass and the pyrolysis gas are subjected to high-temperature melting gasification, and a high-temperature melt and gasification gas are generated under the condition of pure oxygen or oxygen enrichment. The gasification furnace is at least divided into three temperature zones: the temperature of the upper gas phase space is 900-1400 ℃, the temperature of the middle and lower biomass gasification areas is 1200-2000 ℃, and the temperature of the tail melt flowing area is 1400-2000 ℃; the operation pressure of the gasification furnace is-0.1 MPaG to 2.0 MPaG.

The post-treatment unit is used for chilling and washing the gasified gas to obtain purified gas, and discharging the high-temperature melt after the high-temperature melt flows uniformly. The post-treatment unit comprises a mixed gas treatment unit and a high-temperature melt treatment unit which are respectively arranged at the top and the bottom of the gasification unit.

The mixed gas treatment unit comprises a quenching tank 8 and a washing tower 9 which are sequentially connected with the gasification unit, and the high-temperature mixed gas leaves the gasification furnace from the top, enters the quenching tank for quenching, and is sent to the washing tower for washing and purification. Mixed purified gas group after washing tower purificationThe formation (V%) is: CO content of 10-45%, H₂Content 10% -50%, CH₄0-30% of CO₂0 to 15 percent of N₂The content is 5-30%. .

The mixed gas treatment unit also comprises a water treatment system 10, wherein the water treatment system is connected with the washing tower and the chilling tank, and washing water generated by the washing tower is treated by the water treatment system and then is circulated back to the chilling tank to be used as chilling liquid for recycling.

The high-temperature melt processing unit comprises a homogenizing channel 7, and the high-temperature melt flows in the homogenizing channel for a period of time and then is discharged out of the system to obtain molten glass with uniform properties and stable structure.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.