Biomass pyrolysis gasification system and method

Abstract

The invention provides a biomass pyrolysis gasification system and method.The system comprises a biomass pyrolysis hydrogen production unit, the biomass pyrolysis hydrogen production unit comprises a biomass pyrolysis assembly, a slurry making assembly and a biogas separation assembly, and the biomass pyrolysis assembly is in heat exchange connection with a bio-slurry oil gasification unit so that biomass raw materials can be pyrolyzed into biochar and oil dust gas; the oil-dust gas is treated by the biogas separation assembly to separate oil dust, water and hydrogen-rich biogas; the biochar and the oil dust enter a pulping assembly to obtain bio-oil slurry; the bio-oil slurry gasification unit comprises an entrained-flow bed gasification furnace, bio-oil slurry, separated water and a gasification agent enter the entrained-flow bed gasification furnace for gasification treatment, generated gasified slag is discharged after being cooled, and meanwhile generated crude biogas exchanges heat with biomass raw materials after waste heat is recycled. Biomass is pyrolyzed, a pyrolyzed bio-oil-dust mixture and biochar are prepared into bio-oil slurry for gasification, meanwhile, pyrolysis wastewater is co-treated, and the final product is hydrogen-rich biogas.

Description

Technical Field

[0001] The present application relates to the technical field of biomass hydrogen production, and in particular to a system and method for biomass pyrolysis and gasification. Background Art

[0002] Construct a clean, low-carbon, low-cost diversified hydrogen production system, and develop renewable energy hydrogen production. Biomass, as a renewable resource with abundant output, low price and high hydrogen content, has irreplaceable advantages in hydrogen production. The thermochemical utilization of biomass mainly adopts combustion, pyrolysis, gasification and other technologies. At present, most of them use combustion to obtain heat, which causes great waste of renewable resources.

[0003] Among them, biomass pyrolysis is generally divided into pyrolysis carbonization, pyrolysis gasification, and pyrolysis liquefaction. Biomass carbonization generally uses a biomass pyrolysis furnace to heat biomass through a heat source to produce biochar. There are many types of pyrolysis furnaces, which are generally divided into internal heating and external heating types. The heat carrier is divided into gas heat carrier and solid heat carrier. Most of the direct gasification of biomass uses a fixed bed, and a few use a fluidized bed. Among them, the technology of using fluidized bed gasification to produce hydrogen-rich coal gas helps to improve the biomass carbon conversion rate and is more conducive to the large-scale biomass gasification technology; however, fluidized bed gasification requires the raw material particle size to be less than 0.1mm, and the flexibility of biomass raw materials makes powder making and pneumatic conveying very difficult. Summary of the invention

[0004] The present application aims to solve at least one of the technical problems in the related art to a certain extent. The present application proposes a system and method for pyrolysis and gasification of biomass, which pyrolyzes biomass, and makes a bio-oil slurry with biochar after pyrolysis for gasification, and simultaneously treats pyrolysis wastewater in a coordinated manner. The final product is hydrogen-rich biogas, because the present application solves the problems of powdering and transportation caused by the flexibility of biomass raw materials and the problem of oil-dust separation during biomass pyrolysis, and realizes the efficient production of hydrogen-rich biogas from renewable resources such as biomass.

[0005] To achieve the above objectives, the first aspect of the present application proposes a biomass pyrolysis and gasification system, comprising:

[0006] A biomass pyrolysis hydrogen production unit, comprising a biomass pyrolysis component, a pulping component and a biogas separation component, wherein the biomass pyrolysis component is heat exchange connected with a bio-oil slurry gasification unit to pyrolyze the biomass raw material to form biochar and oil dust gas; the oil dust gas is processed by the biogas separation component to separate oil dust, water and hydrogen-rich biogas; the biochar and the oil dust enter the pulping component to obtain bio-oil slurry;

[0007] The bio-oil slurry gasification unit comprises an entrained flow gasifier, wherein the bio-oil slurry, the separated water and the gasifying agent enter the entrained flow gasifier for gasification treatment, the generated gasified slag is discharged after being cooled, and the waste heat of the generated raw biogas is recovered and exchanged with the biomass raw material.

[0008] In some embodiments, the biomass pyrolysis component includes a crushing part and a pyrolysis part arranged in sequence upstream and downstream, wherein the biomass raw material enters the crushing part and is crushed to a set fineness, and then enters the pyrolysis part for pyrolysis.

[0009] In some embodiments, the biogas separation component includes a first washing separation element and a second washing separation element, wherein the oily gas enters the first washing separation element and the second washing separation element in sequence and is washed and cooled using bio-oil and water respectively to separate the oily gas, the separation water and the hydrogen-rich biogas.

[0010] In some embodiments, the pulping component includes a grinding part and a pulping part; the biochar enters the grinding part and is ground to a set fineness, and then is transported to the pulping part; the first washing and separation part is connected to the pulping part to pulp the oil dust.

[0011] In some embodiments, the bio-oil slurry gasification unit further comprises a burner, which is connected to the fluidized flow gasifier; the burner is connected to the second washing separation element, and the bio-oil slurry and the separation water enter the fluidized flow gasifier through the burner.

[0012] In some embodiments, the bio-oil slurry gasification unit also includes a waste heat recovery component, which is connected to the fluidized flow gasifier and is also heat exchange connected to the biomass pyrolysis component to recover the waste heat of the raw biogas and exchange it with the biomass raw material.

[0013] According to the second aspect, the present application proposes a method for pyrolysis and gasification of biomass, which uses the system described in any of the above embodiments to perform pyrolysis and gasification of biomass, including the following steps:

[0014] Pyrolyzing the biomass raw material to form biochar and oil dust gas, wherein the oil dust gas is subjected to washing treatment to separate oil dust, water and hydrogen-rich biogas; pulping the biochar and the oil dust to obtain bio-oil pulp;

[0015] The bio-oil slurry, the separated water and the gasifying agent enter the fluidized-bed gasifier for gasification treatment, and the generated gasified slag is discharged after cooling. Meanwhile, the generated crude biogas waste heat is recovered and then exchanged with the biomass raw material to achieve pyrolysis of the biomass raw material.

[0016] In some embodiments, the biomass raw material is at least one of crop straw, firewood, forest waste, and energy plants, and its fineness is less than 100 mm;

[0017] and / or, the biomass raw material is pyrolyzed at 350-550° C.;

[0018] and / or, the biochar is cooled to a temperature not exceeding 100° C. before pulping;

[0019] and / or, the pulping method is wet pulping, the viscosity of the bio-oil pulp is less than 1500 mPa.s, and the concentration of the biochar is ≤60% by mass percentage;

[0020] And / or, 90% of the biochar in the bio-oil slurry has a particle size of ≤20 mesh.

[0021] In some embodiments, the temperature of the oil dust gas is 200-400° C., and the oil dust is first washed with bio-oil to cool to 110-150° C., and then washed with water to separate the separated water and the hydrogen-rich bio-gas.

[0022] And / or, the volume percentage of hydrogen in the hydrogen-rich biogas is 20-60%.

[0023] In some embodiments, the gasifying agent is pure oxygen or oxygen-enriched gas;

[0024] and / or, the temperature of the gasification treatment in the entrained flow gasifier is 1000-1500° C., and the gasification pressure is 0-6.5 MPa;

[0025] And / or, after the waste heat of the raw biogas is recovered to generate saturated steam or superheated steam, the temperature is reduced to 700-1000° C. and then heat exchanged with the biomass raw material.

[0026] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0028] Figure 1 is a schematic structural diagram of a biomass pyrolysis and gasification system in one embodiment of the present application;

[0029] Figure 2 is a flow chart of a method for pyrolysis and gasification of biomass in one embodiment of the present application;

[0030] In the figure, 1, crushing part; 2, pyrolysis part; 3, grinding part; 4, pulping part; 5, first washing and separation part; 6, second washing and separation part; 7, burner; 8, fluidized bed gasification furnace; 9, waste heat recovery component. DETAILED DESCRIPTION

[0031] Embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements with the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application, and cannot be construed as limiting the present application. On the contrary, the embodiments of the present application include all changes, modifications and equivalents that fall within the spirit and connotation of the appended claims.

[0032] To achieve the above objectives, the present application first proposes a biomass pyrolysis and gasification system. Figure 1 As shown, it includes: a biomass pyrolysis hydrogen production unit and a bio-oil slurry gasification unit; the biomass pyrolysis hydrogen production unit includes a biomass pyrolysis component, a pulping component and a biogas separation component, the biomass pyrolysis component is heat-exchange connected with the bio-oil slurry gasification unit to pyrolyze the biomass raw material to form biochar and oil dust gas; the oil dust gas is processed by the biogas separation component to separate oil dust, separate water and hydrogen-rich biogas; the biochar and oil dust enter the pulping component to obtain bio-oil slurry.

[0033] Among them, the biomass pyrolysis hydrogen production unit includes a biomass pyrolysis component, a pulping component and a biogas separation component, wherein the biomass pyrolysis component is connected to the bio-oil slurry gasification unit for heat exchange, and the biomass pyrolysis component utilizes the cooled raw biogas output by the bio-oil slurry gasification unit to pyrolyze the biomass raw material into biochar and oil dust gas; the oil dust gas is processed by the biogas separation component to separate oil dust, separate water and hydrogen-rich biogas; the biochar and oil dust enter the pulping component to obtain bio-oil slurry.

[0034] The biomass raw material is at least one of crop straw, firewood, forest waste, and energy plants. The biomass pyrolysis component includes a crushing part 1 and a pyrolysis part 2 arranged in sequence upstream and downstream. The biomass raw material enters the crushing part 1 and is crushed to a set fineness, and then enters the pyrolysis part 2 for pyrolysis. It can be seen that at least one of crop straw, firewood, forest waste, and energy plants is input into the crushing part 1 for crushing to make its fineness less than 100mm; the biomass raw material with a fineness less than 100mm is sent to the pyrolysis part 2, and the pyrolysis part 2 is connected to the bio-oil slurry gasification unit for heat exchange. The raw biogas after cooling output by the biomass pyrolysis component enters the pyrolysis part 2 for heat exchange with the biomass raw material, and the biomass raw material is pyrolyzed to form biochar and oil dust gas. This embodiment uses pyrolysis to break the flexibility of the biomass raw material.

[0035] In this embodiment, the biogas separation component includes a first washing and separation component 5 and a second washing and separation component 6, wherein the oily gas enters the first washing and separation component 5 and the second washing and separation component 6 in sequence and is washed and cooled by bio-oil and water respectively to separate the oily gas, separated water and hydrogen-rich biogas. In other words, the biogas separation component includes a first washing and separation component 5 and a second washing and separation component 6, wherein the oily gas first enters the first washing and separation component 5 to be washed and cooled by bio-oil to separate the oily gas, and the washing temperature is controlled to be above the dew point of water vapor in the oily gas to prevent the water in the oily gas from entering the bio-oil, wherein the bio-oil refers to a liquid formed by the high molecular polymers constituting the biomass being cracked into low molecular organic vapor by rapid heating under the condition of oxygen isolation, and condensed by a quenching method. In this embodiment, the washing method is to use the cooled circulating bio-oil to wash in the bio-oil washing tower, directly contact the bio-oil with the oily gas for heat exchange, reduce the temperature of the oily gas to 110-150°C, wash off the condensed bio-oil in the oily gas, and wash off the dust in the oily gas at the same time.

[0036] The wet biogas outputted from the first washing and separation element 5 is passed into the second washing and separation element 6, and the separated water and the hydrogen-rich biogas in the wet biogas are separated by water washing in the second washing and separation element 6, wherein the washing method is to use cooled circulating water to wash in a washing tower, and the separated water is directly contacted with the wet biogas outputted from the first washing and separation element 5 for heat exchange, so as to reduce the temperature of the wet biogas, wash off the condensed water in the wet biogas, and cool down to obtain the hydrogen-rich biogas, wherein the volume percentage of hydrogen in the hydrogen-rich biogas is 20-60%.

[0037] In this embodiment, a two-stage oil-water washing process using a first washing and separation element 5 and a second washing and separation element 6 is used. In the oil washing process, the bio-oil dust gas is washed by recycling the cooled bio-oil, and the washed oil dust is used to prepare the bio-oil slurry. There is no oil-dust separation process, which solves the problem of the difficulty of oil-dust separation. The water washing process avoids the formation of a large amount of bio-oil water, and there is no large amount of oil-water separation process, which solves the problem of the difficulty of the bio-oil-water separation process.

[0038] The pulping assembly includes a grinding part 3 and a pulping part 4. The biochar output by the pyrolysis part 2 enters the grinding part 3 and is ground to a set fineness before being transported to the pulping part 4. At the same time, the first washing and separation part 5 is connected to the pulping part 4. The oil dust output by the first washing and separation part 5 enters the pulping part 4 and is pulped together with the biochar. In this embodiment, the fly ash generated by the gasification and pyrolysis of the biomass raw material, i.e., biochar and oil dust are separated and then pulped, which increases the ash content of the biomass raw material, solves the problem of poor slag hanging in the furnace and damage to the furnace wall during gasification caused by the low ash content of the biomass raw material, and can improve the stability of the system operation and extend the life cycle of the system.

[0039] The bio-oil slurry gasification unit comprises an entrained flow gasifier 8, in which the bio-oil slurry, separated water and gasifying agent enter into the entrained flow gasifier 8 for gasification treatment, and the generated gasified slag is discharged after being cooled, while the generated raw biogas waste heat is recovered and exchanged with the biomass raw material.

[0040] Among them, the bio-oil slurry gasification unit includes an entrained flow gasifier 8. In some embodiments, the bio-oil slurry gasification unit also includes a burner 7, which is connected to the entrained flow gasifier 8; the burner 7 is respectively connected to the second washing and separation component 6 and the pulping component 4, and the bio-oil slurry and separated water enter the entrained flow gasifier 8 through the burner 7; at the same time, a gasifying agent is introduced into the burner 7 to realize the gasification of the bio-oil slurry and the treatment of water.

[0041] It is known that the separated water output by the second washing and separation element 6 contains a small amount of bio-oil, so it enters the fluidized bed gasifier 8 through the burner 7 for gasification and incineration, without wastewater discharge, thus solving the problem of a large amount of wastewater generated during the gasification process. At the same time, the bio-oil slurry enters the fluidized bed gasifier 8, and the gasification slag produced by gasification is discharged after cooling. The raw biogas produced by gasification can be recovered through waste heat and then heat exchanged with the biomass raw material to achieve pyrolysis of the biomass raw material. Therefore, the present application adopts the fluidized bed gasifier 8 to gasify the bio-oil slurry. Compared with the problems of low carbon conversion rate and low cold gas efficiency when using fixed bed and fluidized bed gasification to process biomass raw materials in the related art, the present application can increase the carbon conversion rate of biomass raw materials by about 10-20%, and the cold gas efficiency by about 10%, and is more conducive to the large-scale production of hydrogen from biomass. In addition, biochar and bio-oil are used to prepare bio-oil slurry for subsequent gasification. Bio-oil slurry is easy to prepare, has a low water content, and does not require a drying stage. This solves the problems of high water content in the raw materials for water-coal slurry gasification and low cold gas efficiency of the system. It also solves the problem of biomass flexibility, avoids the complex and accident-prone process of dry powder pneumatic conveying and dry powder gasification coal grinding, improves the thermal efficiency of the system, and can promote the efficient and comprehensive utilization of biomass and broaden the utilization direction of biomass.

[0042] In some embodiments, the bio-oil slurry gasification unit further includes a waste heat recovery component 9, which is connected to the fluidized flow gasifier 8 and is also connected to the biomass pyrolysis component for heat exchange, so as to recover the waste heat of the raw biogas and exchange heat with the biomass raw material. For example, the waste heat recovery component 9 is a waste boiler, which recovers the waste heat of the raw biogas after gasification by the fluidized flow gasifier 8, and uses the raw biogas containing low-temperature waste heat as a heat carrier to pyrolyze the biomass raw material, thereby solving the problem of waste of sensible heat of biogas in the quenching process.

[0043] The present application adopts bio-oil slurry gasification, which is easy to prepare, has a low water content, and does not require a drying stage, thereby solving the problems of high water content of raw materials in water-coal slurry gasification and low cold gas efficiency of the system; and solving the problem of complex dry powder gasification coal grinding process and proneness to accidents.

[0044] According to the second aspect, the present application proposes a method for pyrolysis and gasification of biomass, using the system in any of the above embodiments to perform pyrolysis and gasification of biomass. Figure 2 As shown, the following steps are included:

[0045] S1: Pyrolyzing biomass raw materials to form biochar and oil dust gas, and washing the oil dust gas to separate oil dust, water and hydrogen-rich biogas; pulping the biochar and oil dust to obtain bio-oil pulp;

[0046] S2: The bio-oil slurry, separated water and gasifying agent enter the fluidized-flow gasifier 8 for gasification treatment. The generated gasified slag is discharged after cooling. Meanwhile, the generated crude biogas is recovered for waste heat and then exchanged with the biomass raw material to achieve pyrolysis of the biomass raw material.

[0047] Among them, the biomass raw material in S1 is at least one of crop straw, firewood, forest waste, and energy plants, which is input into the crushing part 1 for crushing to make its fineness less than 100mm; the biomass raw material with a fineness less than 100mm is sent to the pyrolysis part 2, and the pyrolysis part 2 is connected with the bio-oil slurry gasification unit for heat exchange. The raw biogas after cooling output by the biomass pyrolysis component enters the pyrolysis part 2 for heat exchange with the biomass raw material, and the biomass raw material is pyrolyzed at 350-550℃ to form biochar and oil dust gas. For example, the biomass raw material is pyrolyzed at 350℃, 400℃, 500℃, and 550℃ to form biochar and oil dust gas.

[0048] After the biochar produced by the pyrolysis element 2 is cooled to no more than 100°C, it enters the grinding element 3 and is ground to less than 0.1mm, and is input into the pulping element 4 for pulping; at the same time, the oil dust gas produced by the pyrolysis element 2 is 200-400°C, which first enters the first washing and separation element 5 and is washed in the bio-oil washing tower with the cooled circulating bio-oil, so that the bio-oil and the oil dust gas are directly contacted for heat exchange, and the temperature of the oil dust gas is reduced to 110-150°C, and the condensed bio-oil in the oil dust gas is washed down, and the dust in the oil dust gas is washed down at the same time; and the washing temperature is controlled to be above the dew point of water vapor in the oil dust gas to prevent water from the oil dust gas from entering the bio-oil. The wet biogas outputted from the first washing and separation element 5 is passed into the second washing and separation element 6, and the separated water and the hydrogen-rich biogas in the wet biogas are separated by water washing in the second washing and separation element 6, wherein the washing method is to use cooled circulating water to wash in a washing tower, and the separated water is directly contacted with the wet biogas outputted from the first washing and separation element 5 for heat exchange, so as to reduce the temperature of the wet biogas, wash off the condensed water in the wet biogas, and cool down to obtain the hydrogen-rich biogas, wherein the volume percentage of hydrogen in the hydrogen-rich biogas is 20-60%.

[0049] The biochar ground in this step and the oil dust output from the first washing and separation element 5 enter the pulping element 4, which can be a mill, that is, the ground biochar and oil dust enter the mill for wet pulping, and the viscosity of the obtained bio-oil slurry is less than 1500mPa.s, and the concentration of biochar is ≤60% in terms of mass percentage; 90% of the biochar in the bio-oil slurry has a particle size of ≤20 mesh.

[0050] In S2, the bio-oil slurry, separated water and gasifying agent obtained in S1 are introduced into the fluidized flow gasifier 8 through the burner 7 for gasification treatment, wherein the gasifying agent is pure oxygen or oxygen-enriched gas; the temperature of the gasification treatment in the fluidized flow gasifier 8 is 1000-1500°C, and the gasification pressure is 0-6.5MPa; the gasified slag produced by the gasification treatment in the fluidized flow gasifier 8 is discharged after cooling, and the crude biogas produced at the same time is recovered from the waste heat of the crude biogas to generate saturated steam or superheated steam, and the temperature is reduced to 700-1000°C and then heat exchanged with the biomass raw material.

[0051] The following is an example of the method of biomass pyrolysis and gasification of the present application: 11.5t / h corn stalks with a moisture content of 13% are crushed into 50mm pieces and enter the pyrolysis unit 2 with a 13540Nm 3 / h, 850℃ raw biogas heat exchange and pyrolysis at 450℃, pyrolysis produces 3.2t / h 450℃ biochar and 8.3t / h 300℃ oil dust gas, 450℃ biochar is cooled to below 100℃, 300℃ oil dust gas and raw biogas are mixed and enter the first washing and separation element 5 to cool to 123℃, 5.6t / h 123℃ oil dust is recovered, the raw biogas at 123℃ output by the first washing and separation element 5 is washed with water to room temperature, and 12250Nm 3 / h of hydrogen-rich biogas, the effective gas component of hydrogen-rich biogas is 85.1%, and the hydrogen content is 30%. The oil dust cooled to room temperature is mixed with biochar and enters the pulping component to make 8.8t / h of bio-oil slurry with a biochar concentration of 36%. The bio-oil slurry is mixed with 3140Nm 3 / h of 99.6% pure oxygen enters the burner 7 and is gasified under the conditions of 1350℃ and 0.6MPa(G) in the gasifier to produce 13540Nm 3 / h of raw biogas, which is cooled to 850℃ in a waste boiler to recover the waste heat of the raw biogas and produce 4.2t / h of steam. The specific oxygen consumption of this process is 301338Nm 3 / kNm 3 (CO+H2), specific biomass consumption (dry basis) is 959kg / kNm 3 (CO+H2), the cold gas efficiency is 80.2% and the carbon conversion rate is 99%.

[0052] As a comparative example, 11.5 t / h corn stalks with a moisture content of 13% were crushed and fed into a forming machine, where they were squeezed into small pieces ≤ 10 mm in size and then fed into a circulating fluidized bed gasifier for gasification at 800°C and 20 kPa (G), where the gasifying agent was 3040 Nm 3 / h of 99.6% pure oxygen and 5750kg / h of steam, the biogas generated by the reaction is 14600Nm 3 / h, the effective gas component of biogas is 61.5%, and the specific oxygen consumption of the process is 338Nm 3 / kNm 3 (CO+H2), specific biological consumption (dry basis) is 1113kg / kNm 3 (CO+H2), the cold gas efficiency is 71.4%, and the carbon conversion rate is 90% (without considering the impact of the low melting point of biomass ash on the solid slag discharge of the circulating fluidized bed).

[0053] It should be noted that, in the description of this application, the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. In addition, in the description of this application, unless otherwise specified, the meaning of "plurality" is two or more.

[0054] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, segment or portion of code that includes one or more executable instructions for implementing the steps of a specific logical function or process, and the scope of the preferred embodiments of the present application includes alternative implementations in which functions may not be performed in the order shown or discussed, including performing functions in a substantially simultaneous manner or in the reverse order depending on the functions involved, which should be understood by technicians in the technical field to which the embodiments of the present application belong.

[0055] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0056] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A biomass pyrolysis and gasification system, characterized in that: include: A biomass pyrolysis hydrogen production unit, comprising a biomass pyrolysis component, a pulping component and a biogas separation component, wherein the biomass pyrolysis component is heat exchange connected with a bio-oil slurry gasification unit to pyrolyze the biomass raw material to form biochar and oil dust gas; the oil dust gas is processed by the biogas separation component to separate oil dust, water and hydrogen-rich biogas; the biochar and the oil dust enter the pulping component to obtain bio-oil slurry; The bio-oil slurry gasification unit comprises an entrained flow gasifier, wherein the bio-oil slurry, the separated water and the gasifying agent enter the entrained flow gasifier for gasification treatment, the generated gasified slag is discharged after being cooled, and the waste heat of the generated raw biogas is recovered and exchanged with the biomass raw material.

2. The system according to claim 1, characterized in that The biomass pyrolysis component comprises a crushing part and a pyrolysis part which are sequentially arranged upstream and downstream, wherein the biomass raw material enters the crushing part and is crushed to a set fineness, and then enters the pyrolysis part for pyrolysis.

3. The system according to claim 1, characterized in that The biogas separation component includes a first washing separation component and a second washing separation component, wherein the oily gas enters the first washing separation component and the second washing separation component in sequence and is washed and cooled by bio-oil and water respectively to separate the oily gas, the separation water and the hydrogen-rich biogas.

4. The system according to claim 3, characterized in that The pulping assembly includes a grinding part and a pulping part; the biochar enters the grinding part and is ground to a set fineness, and then is transported to the pulping part; The first washing and separating element is connected to the pulping element to pulp the oil dust.

5. The system according to claim 4, characterized in that The bio-oil slurry gasification unit further comprises a burner, which is communicated with the entrained flow gasifier; the burner is connected with the second washing and separation element, and the bio-oil slurry and the separation water enter the entrained flow gasifier through the burner.

6. The system according to any one of claims 1 to 5, characterized in that: The bio-oil slurry gasification unit also includes a waste heat recovery component, which is connected to the entrained flow gasifier and is also heat-exchange connected to the biomass pyrolysis component to recover the waste heat of the raw biogas and exchange heat with the biomass raw material.

7. A method for pyrolysis and gasification of biomass, characterized in that: Using the system described in any one of claims 1 to 6 to carry out biomass pyrolysis and gasification, comprising the following steps: Pyrolyzing the biomass raw material to form biochar and oil dust gas, wherein the oil dust gas is subjected to washing treatment to separate oil dust, water and hydrogen-rich biogas; pulping the biochar and the oil dust to obtain bio-oil pulp; The bio-oil slurry, the separated water and the gasifying agent enter the fluidized-bed gasifier for gasification treatment, and the generated gasified slag is discharged after cooling. Meanwhile, the generated crude biogas waste heat is recovered and then exchanged with the biomass raw material to achieve pyrolysis of the biomass raw material.

8. The method according to claim 7, characterized in that The biomass raw material is at least one of crop straw, firewood, forest waste, and energy plants, and its fineness is less than 100 mm; and / or, the biomass raw material is pyrolyzed at 350-550° C.; and / or, the biochar is cooled to a temperature not exceeding 100° C. before pulping; and / or, the pulping method is wet pulping, the viscosity of the bio-oil pulp is less than 1500 mPa.s, and the concentration of the biochar is ≤ 60% by mass percentage; And / or, 90% of the biochar in the bio-oil slurry has a particle size of ≤20 mesh.

9. The method according to claim 7, characterized in that: The temperature of the oil dust gas is 200-400°C, and the oil dust is firstly separated by washing with bio-oil to cool it down to 110-150°C; and then washed with water to separate the separated water and the hydrogen-rich bio-gas; And / or, the volume percentage of hydrogen in the hydrogen-rich biogas is 20-60%.

10. The method according to claim 7, characterized in that The gasifying agent is pure oxygen or oxygen-rich gas; and / or, the temperature of the gasification treatment in the entrained flow gasifier is 1000-1500° C., and the gasification pressure is 0-6.5 MPa; And / or, after the waste heat of the raw biogas is recovered to generate saturated steam or superheated steam, the temperature is reduced to 700-1000° C. and then heat exchanged with the biomass raw material.

Images