Method for preparing synthesis gas from biomass

Abstract

The invention discloses a method for preparing synthesis gas from biomass, which adopts a production line for preparing synthesis gas from biomass, and comprises the following steps: (1) preparing high-temperature steam by adopting a steam heater: continuously introducing high-temperature gas into a high-temperature gas heat exchange channel of the steam heater, and after introducing the high-temperature gas for 2-5 minutes, continuously introducing the high-temperature gas into a high-temperature gas heat exchange channel of the steam heater; steam is continuously introduced into a steam heat exchange channel of the steam heater through the steam boiler while the high-temperature gas is continuously introduced; (2) preparing synthesis gas by adopting a gasification reactor: continuously introducing a material into a gasification reaction chamber of the gasification reactor through a feeding auger, and introducing high-temperature steam into the gasification reaction chamber through a steam heater, a steam inlet pipe and each hood structure while continuously introducing the material after the material level of the material in the gasification reaction chamber reaches a set position, and the high-temperature steam and the materials move oppositely. According to the method, the biomass raw material or the biochar can be subjected to sufficient gasification reaction under high-temperature steam of 800 DEG C or above.

Description

Technical Field

[0001] The present invention relates to the technical field of steam gasification, and particularly to a preparation method for preparing synthesis gas from biomass. Background Art

[0002] Biomass refers to the general term for various organic substances formed directly or indirectly by photosynthesis. It has the advantages of renewable, rich reserves, low pollution, and storability. It is the fourth largest energy source after coal, oil, and natural gas, and is also an ideal renewable energy source.

[0003] Steam gasification technology is an important technology for utilizing biomass. It uses high-temperature steam as a gasifying agent to gasify biomass raw materials and finally converts them into hydrogen-rich synthesis gas.

[0004] The transformation of steam gasification technology achievements into a production line for preparing synthesis gas from biomass. The most critical links in this production line are the gasification reactor and the supply of high-temperature steam.

[0005] For the gasification reactor, in currently common gasification reactors, biomass raw materials are added from the top of the gasification reactor, and the gasifying agent (i.e., high-temperature steam with a temperature above 800 °C) is added from the bottom of the gasification reactor. The flow direction of the steam is opposite to that of the biomass raw materials. The downward-flowing biomass raw materials are dried, cracked, and gasified by the upward-flowing steam. During the gasification reaction process, since the rising steam cannot be evenly diffused and distributed, some biomass raw materials fail to come into full contact with the steam, resulting in incomplete gasification reaction, problems such as a large amount of residue, tar generation, inability to improve gasification efficiency, and limitations.

[0006] For the supply of high-temperature steam, during the gasification reaction process, the temperature of the high-temperature steam introduced into the gasification reactor needs to be maintained above 800 °C. However, for currently common steam boilers on the market, although the use cost is low, the highest temperature of the produced steam can only reach about 150 °C, which cannot meet the temperature requirements of the high-temperature steam required by the gasification reactor. Summary of the Invention

[0007] The technical problems to be solved by the present invention are: to provide a production line for preparing synthesis gas from biomass that can enable biomass raw materials or biochar to undergo a full gasification reaction to generate synthesis gas under high-temperature steam above 800 °C, as well as a preparation method for preparing synthesis gas from biomass. This production line has the advantages of high gasification efficiency, basically no tar residue, and basically no carbon residue. The synthesis gas produced by using this production line mainly consists of CO and H2, with a small amount of CO2. Among them, the hydrogen component accounts for about 60%, and it can be used for making green methanol, hydrogen production, etc. Especially when synthesizing green methanol, it can be directly synthesized without adding other substances.

[0008] In view of the problems existing in the existing gasification reactors, such as low gasification efficiency, large residue, and difficulty in the source of high-temperature steam required for gasification reaction, the technical solution adopted in the present invention is as follows: The biomass-to-syngas production line includes: a steam boiler, a steam heater, and a gasification reactor; wherein, the steam boiler and the steam heater are combined to provide high-temperature steam at a temperature above 800°C.

[0009] The steam heater has two heat exchange channels: a high-temperature gas heat exchange channel and a steam heat exchange channel. The positions of the high-temperature gas heat exchange channel and the steam heat exchange channel are set such that the steam entering the steam heat exchange channel can indirectly exchange heat with the high-temperature gas entering the high-temperature gas heat exchange channel; The structure of the gasification reactor includes: a reaction furnace composed of an inner furnace body and an outer furnace body. A closed hollow interlayer is formed between the inner furnace body and the outer furnace body; an air outlet pipe communicating with the hollow interlayer is provided on the outer side wall of the top of the outer furnace body; an air inlet pipe communicating with the hollow interlayer is provided on the outer side wall of the bottom of the outer furnace body; A feeding auger communicating with the furnace chamber of the inner furnace body is provided on the outer side wall of the top of the inner furnace body; a syngas conveying pipeline communicating with the furnace chamber of the inner furnace body is provided on the top of the inner furnace body; the bottom of the inner furnace body has an open mouth communicating with the furnace chamber of the inner landlift. An ash discharge hopper is hermetically installed at the open mouth, and an ash discharge valve is installed at the ash discharge port of the ash discharge hopper; A refractory cement casting partition layer is provided in the lower section of the furnace chamber of the inner furnace body. The refractory cement casting partition layer divides the furnace chamber of the inner furnace body into two upper and lower chambers: a gasification reaction chamber and a partition chamber; an ash discharge channel penetrating up and down is opened in the middle of the refractory cement casting partition layer; a number of installation channels penetrating up and down are evenly spaced on the refractory cement casting partition layer. A wind cap structure is correspondingly arranged in each installation channel, and the parts where the air outlet holes on the wind cap structure are located extend above the corresponding installation channels; A ring-shaped pipeline is provided in the partition chamber. A first connection hole and a number of second connection holes are opened on the ring-shaped pipeline. A steam inlet pipe is hermetically connected at the first connection hole. The steam inlet pipe hermetically passes through a through hole on the reaction furnace and extends outside the reaction furnace; each second connection hole is respectively in one-to-one correspondence with the air inlet holes at the bottom of each wind cap structure, and the air inlet holes at the bottom of each wind cap structure are hermetically connected to the corresponding second connection holes; A refractory layer is wrapped outside the reaction furnace. The outlet of the air outlet pipe, the inlet of the air inlet pipe, the inlet of the steam inlet pipe, and the inlet of the feeding auger are all located outside the refractory layer; High-temperature steam (at a temperature of about 800 °C) enters each air cap structure through the steam inlet pipe and the annular pipeline, and then enters the gasification reaction chamber through each air hole on each air cap structure. The air cap structure is set here to enable the high-temperature steam to be more evenly distributed in the gasification reaction chamber, so that the materials entering the gasification reaction chamber can come into full contact with the high-temperature steam to undergo a gasification reaction, improving the gasification reaction efficiency. With the assistance of the above-mentioned hollow sandwich for auxiliary heating, the gasification reaction efficiency is further improved.

[0010] Materials such as biomass raw materials and biochar prepared from biomass raw materials enter the furnace cavity of the inner furnace body through the feeding auger, and come into contact with the high-temperature steam entering the gasification reaction chamber through each air hole on each air cap structure. The materials move from top to bottom, and the high-temperature steam moves from bottom to top. The ash after the gasification reaction drops downward through the ash discharge channel, while the syngas after the gasification reaction rises and is output outside the reaction furnace through the syngas pipeline.

[0011] The steam outlet of the steam boiler is connected to the steam inlet of the steam heat exchange channel in the steam heater through the first connecting pipeline, and the steam outlet of the steam heat exchange channel in the steam heater is connected to the steam inlet pipe of the gasification reactor through the second connecting pipeline. During operation, the steam boiler produces steam at about 150 °C. This steam enters the steam heat exchange channel in the steam heater through the first connecting pipeline. High-temperature gas (the temperature of the high-temperature gas is usually about 1000 °C) is introduced into the high-temperature gas heat exchange channel of the steam heater. The high-temperature gas releases heat to the steam in the steam heat exchange channel, thereby raising the temperature of the steam in the steam heat exchange channel to above 800 °C.

[0012] The preparation method of the biomass-derived syngas uses the biomass-derived syngas production line described in this solution. The preparation method of the biomass-derived syngas is as follows: (1) Prepare high-temperature steam using a steam heater: Continuously introduce high-temperature gas into the high-temperature gas heat exchange channel of the steam heater. The temperature of the high-temperature gas is greater than 900 °C. After the high-temperature gas is introduced for 2 - 5 minutes, while the high-temperature gas is continuously introduced, continuously introduce steam into the steam heat exchange channel of the steam heater through the steam boiler. The temperature of the steam is greater than 100 °C. The heat exchange path lengths of the high-temperature gas heat exchange channel and the steam heat exchange channel ensure that the temperature of the high-temperature steam output from the steam heat exchange channel is greater than 800 °C. (2) Prepare syngas using a gasification reactor: Materials are continuously fed into the gasification reaction chamber of the gasification reactor through a feeding auger. The materials move from top to bottom. The materials are biomass raw materials or biochar, with a length less than 30 mm and a thickness less than 10 mm. The material feeding rate is determined according to the size of the gasification reactor. After testing, the minimum material feeding rate is 100 kg / h, and the maximum can reach 5000 kg / h. When the material level in the gasification reaction chamber reaches the set position, while the materials are continuously fed, high-temperature steam is introduced into the gasification reaction chamber through a steam heater, a steam inlet pipe, and each air cap structure. The high-temperature steam flows from bottom to top, and the flow rate of the high-temperature steam is in a 1:1 ratio with the feeding rate.

[0013] Traditional steam boilers rely on burning coal to obtain heat. Considering economic and environmental protection issues, biomass raw materials are used in this solution. Whether it is a steam boiler, the high-temperature gas in the heat exchange channel where high-temperature gas is introduced into the steam heater, or the high-temperature gas in the hollow interlayer where high-temperature gas is introduced into the gasification reactor, biomass raw materials are used. The specific solution is to set up a biomass carbonization furnace, a first biomass gasification furnace, and a second biomass gasification furnace. A front auger is provided at the biochar outlet of the biomass carbonization furnace, and the discharge port of the front auger is connected to the feed port of the feed auger. Using biochar as the gasification raw material has more advantages than using biomass raw materials, and it can better ensure no residue in the process of generating synthesis gas through gasification reaction. That is, in step (2) of the method for preparing synthesis gas from biomass, the material is biochar, and the biochar is derived from the biomass carbonization furnace.

[0014] The combustible gas outlet of the first biomass gasification furnace is connected to the fuel supply inlet of the steam boiler through a third connecting pipeline. The biomass raw materials are gasified in the first biomass gasification furnace to generate combustible gas, and the generated combustible gas is introduced into the steam boiler as fuel. That is, in step (1) of the method for preparing synthesis gas from biomass, the fuel of the steam boiler is derived from the combustible gas generated by the gasification of the first biomass gasification furnace, and the steam temperature generated by the steam boiler is 120 - 160 °C.

[0015] A combustion chamber is provided at the gas inlet of the high-temperature gas heat exchange channel in the steam heater. The combustible gas outlet of the second biomass gasifier is connected to a first burner provided on the combustion chamber through a fourth connecting pipeline. Biomass raw materials are gasified in the second biomass gasifier to generate combustible gas. The generated combustible gas is introduced into the first burner to burn and generate high-temperature flue gas. The high-temperature flue gas is introduced into the high-temperature gas heat exchange channel as high-temperature gas to indirectly exchange heat with the steam introduced into the steam heater, so as to increase the steam temperature. That is, in step (1) of the method for preparing synthesis gas from biomass, the high-temperature gas introduced into the high-temperature gas heat exchange channel of the steam heater is high-temperature flue gas, which is obtained by burning the combustible gas gasified by the second biomass gasifier in the combustion chamber, and the temperature of the high-temperature flue gas is 1000-1200 °C.

[0016] The synthesis gas delivery pipeline of the gasification reactor is respectively connected to the synthesis gas supply pipeline and a fifth connecting pipeline. The fifth connecting pipeline is connected to a second burner in the intake pipe provided on the gasification reactor. The synthesis gas supply pipeline is connected to the intake port of the water washing device. For the synthesis gas gasified and produced by the gasification reactor, a small part of the synthesis gas is selected and introduced into the second burner through the fifth connecting pipeline to burn and generate high-temperature flue gas. The high-temperature flue gas is introduced into the hollow interlayer of the gasification reactor as high-temperature gas for auxiliary heating of the interlayer. Usually, a valve for controlling the amount of synthesis gas transported to the second burner is provided on the fifth connecting pipeline, and the valve is used to control how much synthesis gas is selected and introduced into the second burner. That is, in step (2) of the method for preparing synthesis gas from biomass, the high-temperature gas introduced into the hollow interlayer of the gasification reactor is high-temperature flue gas, which is obtained by burning 8%-15% of the synthesis gas, and the temperature of the high-temperature flue gas is 1000-1200 °C.

[0017] For a steam heater that can increase the steam temperature from 150 °C to 800 °C, currently, the steam heaters with such a function on the market have high energy consumption and are uneconomical to use. Unless cost is not considered, but for production enterprises, the economic problem needs to be considered. Therefore, a steam heater with the following structure is designed in this solution. The structure of the steam heater includes a heating furnace body, and the furnace cavity of the heating furnace body is sequentially divided into several cavity units from left to right; The structure within each cavity unit is as follows: In the cavity unit, a first partition plate and a second partition plate are arranged at intervals from top to bottom. The cavity unit is divided into an upper cavity, a middle cavity, and a lower cavity from top to bottom by the first partition plate and the second partition plate. A third partition plate is arranged in the upper cavity, and the upper cavity is divided into a first cavity and a second cavity from left to right by the third partition plate. A first connection port communicating with the first cavity is arranged at the top of the heating furnace body, and the first cavity communicates with the lower cavity through a number of first heat exchange tubes arranged in the middle cavity. A second connection port communicating with the second cavity is arranged at the top of the heating furnace body, and the second cavity communicates with the lower cavity through a number of second heat exchange tubes arranged in the middle cavity. Each first connection port in each cavity unit is communicated with the second connection port in the cavity unit adjacent to the left side of this cavity unit through a steam connection pipe. Each first cavity, each second cavity, each steam connection pipe, each first heat exchange tube, each second heat exchange tube, and each lower cavity constitute a steam heat exchange channel for the steam to flow in a serpentine path. The first connection port in the cavity unit at the leftmost end is the steam outlet of the steam heat exchange channel, and the second connection port in the cavity unit at the rightmost end is the steam inlet of the steam heat exchange channel. The middle cavities in each cavity unit penetrate from left to right, so that the middle cavities in all cavity units communicate to form a high-temperature gas heat exchange channel for high-temperature gas to pass through. An air inlet communicating with the high-temperature gas heat exchange channel is arranged at the left end of the heating furnace body, and the air inlet is the gas inlet of the high-temperature gas heat exchange channel. An air outlet communicating with the high-temperature gas heat exchange channel is arranged at the right end of the heating furnace body, and the air outlet is the gas outlet of the high-temperature gas heat exchange channel.

[0018] The flow direction of the high-temperature gas in the steam heater is as follows: The high-temperature gas enters the high-temperature gas heat exchange channel from the gas inlet and flows from left to right. During the flow of the high-temperature gas, it indirectly exchanges heat with the steam in each first heat exchange tube and each second heat exchange tube passing through, and then flows out from the gas outlet after releasing heat. The flow direction of the steam in the steam heater is as follows: The steam enters the heating furnace body through the steam inlet, first enters the cavity unit at the rightmost end, and successively flows through the second cavity, each second heat exchange tube, the lower cavity, each first heat exchange tube, and the first cavity in the cavity unit at the rightmost end, and then flows left into the adjacent cavity unit. After flowing through the second cavity, each second heat exchange tube, the lower cavity, each first heat exchange tube, and the first cavity in this cavity unit, it continues to flow left in the same flow direction in a serpentine direction, and finally flows out from the steam outlet. During the flow of the steam, the steam flowing through each first heat exchange tube and each second heat exchange tube exchanges heat indirectly with the high-temperature gas in the high-temperature gas heat exchange channel outside the tube and absorbs heat.

[0019] Furthermore, for the aforementioned biomass-to-syngas production line, a more optimal solution is as follows: the furnace cavity of the heating furnace body is in the shape of a cuboid; the first connection port corresponding to each cavity unit is connected to the first cavity of this cavity unit through a frustum-shaped first connecting pipe; the second connection port corresponding to each cavity unit is connected to the second cavity of this cavity unit through a frustum-shaped second connecting pipe; the gas inlet of the high-temperature gas heat exchange channel is connected to the middle cavity in the leftmost cavity unit through a frustum-shaped third connecting pipe; the gas outlet of the high-temperature gas heat exchange channel is connected to the middle cavity in the rightmost cavity unit through a frustum-shaped fourth connecting pipe. The third partition plate in each cavity unit evenly divides the upper cavity in this cavity unit, so that the spaces of the first cavity and the second cavity in this cavity unit are of the same size. The positional relationship among the first partition plate, the second partition plate, the third partition plate, each first heat exchange pipe, and each second heat exchange pipe in each cavity unit is as follows: the first partition plate and the second partition plate are arranged horizontally; the third partition plate is perpendicular to the first partition plate; the axes of each first heat exchange pipe are perpendicular to the first partition plate, and the axes of each second heat exchange pipe are perpendicular to the first partition plate. Each first heat exchange pipe in each cavity unit is evenly spaced, each second heat exchange pipe in each cavity unit is evenly spaced, and the number of first heat exchange pipes in each cavity unit is the same as the number of second heat exchange pipes.

[0020] Furthermore, for the aforementioned biomass-to-syngas production line, a more optimal solution is as follows: it further includes: a heat exchanger and a draft fan, and the gas outlet of the high-temperature gas heat exchange channel is connected to the air inlets of the heat exchanger and the draft fan in sequence through a right-side flue gas pipeline.

[0021] Furthermore, for the aforementioned biomass-to-syngas production line, a more optimal solution is as follows: a number of spiral blades are arranged in the hollow interlayer of the gasification reactor, and each spiral blade is evenly spaced along a spiral line trajectory that spirals upward from bottom to top. Such an arrangement can increase the path of the high-temperature gas, improve the heat exchange efficiency, and further ensure the gasification efficiency.

[0022] Furthermore, for the aforementioned biomass-to-syngas production line, a more optimal solution is as follows: the top of the inner furnace body in the gasification reactor protrudes upward outside the outer furnace body, and the part where the inner furnace body protrudes outside the outer furnace body is a frustum-shaped frustum section; the syngas conveying pipeline is located on the top surface of the frustum section; the feeding auger is located on the side wall of the frustum section.

[0023] Furthermore, for the aforementioned biomass-to-syngas production line, a more optimal solution is as follows: A cooling pipeline is provided in the inner cavity of the ash hopper in the gasification reactor. The water inlet end of the cooling pipeline passes through the first connection through-hole on the ash hopper and the second connection through-hole on the refractory layer wrapped outside the ash hopper in a sealed manner and then extends outside the refractory layer wrapped outside the ash hopper. The water outlet end of the cooling pipeline passes through the third connection through-hole on the ash hopper and the fourth connection through-hole on the refractory layer wrapped outside the ash hopper in a sealed manner and then extends outside the refractory layer wrapped outside the ash hopper. The ash discharge valve is composed of a first valve, a second valve, and a transition section connecting the outlet of the first valve and the inlet of the second valve.

[0024] Furthermore, for the aforementioned biomass-to-syngas production line, a more optimal solution is as follows: The refractory layer wrapped outside the frustum section is the first refractory layer obtained by casting refractory cement; the refractory layer wrapped outside the outer furnace body is a refractory brick layer, and a metal outer shell with several claw nails inside is covered outside the refractory brick layer; the refractory layer wrapped outside the ash hopper is the second refractory layer obtained by casting refractory cement.

[0025] Furthermore, for the aforementioned biomass-to-syngas production line, a more optimal solution is as follows: A level gauge for measuring the material level of the material entering the furnace cavity of the inner furnace body is provided on the reaction furnace in the gasification reactor. During the process of continuously feeding the material into the gasification reaction chamber through the feeding auger, the set position of the material in the gasification reaction chamber is determined by the level gauge; a temperature sensor for measuring the temperature in the furnace cavity of the inner furnace body is provided on the reaction furnace.

[0026] The beneficial effects of the present invention are as follows: ① The steam heater in the biomass-to-syngas production line has the advantages of simple and compact structure, simple operation, low energy consumption, economic and environmental protection, and can efficiently and economically produce high-temperature steam with a temperature above 800 °C; the gasification reactor in the biomass-to-syngas production line has the advantages of high gasification efficiency, basically no tar residue, and basically no residual carbon residue; the syngas produced by using this gasification reactor can be directly synthesized into green methanol without adding other substances, and can also be used for hydrogen production; ② The fuel source of the steam boiler and the high-temperature flue gas fuel source in the steam heater both come from the combustible gas generated by the gasification of the biomass gasifier. The high-temperature flue gas fuel in the gasification reactor comes from a part of the syngas in the gasification reaction. The raw materials in the gasification reactor come from the biochar produced by the carbonization of the biomass carbonization furnace. The entire production line uses green and environmentally friendly biomass raw materials, which are economic, environmentally friendly and have low energy consumption; ③ For the syngas obtained by using the above-mentioned biomass-to-syngas preparation method, the hydrogen content in the syngas can generally reach 40-70%, and the carbon monoxide content can generally reach 20-30%. This equipment has high hydrogen gasification efficiency and economic value, and the proportion of each component of the syngas is convenient to adjust, which is suitable for further processing and synthesizing green methane or directly used for hydrogen production. Brief Description of the Drawings

[0027] Figure 1 is a schematic structural diagram of the production line for preparing syngas from biomass according to the present invention.

[0028] Figure 2 is a schematic structural diagram of the steam heater.

[0029] Figure 3 is Figure 2 a schematic diagram of the partial structure of

[0030] Figure 4 is Figure 2 a schematic diagram of the structure in the top view direction.

[0031] Figure 5 is Figure 4 a schematic diagram of the partial structure inside

[0032] Figure 6 is Figure 5 a schematic diagram of the partial structure of

[0033] Figure 7 is a schematic structural diagram of the gasification reactor.

[0034] Figure 8 is Figure 7 a schematic diagram of the partial structure of

[0035] Figure 9 is Figure 8 a schematic diagram of the structure of the refractory cement casting partition in the top view direction in

[0036] Wherein: 100, biomass carbonization furnace; 200, discharge auger; 300, feed auger; 400, gasification reactor; 500, steam heater; 600, combustion chamber; 700, second biomass gasification furnace; 800, steam boiler; 900, first biomass gasification furnace; 1000, water cooling device; 1, heating furnace body; 10, cavity unit; 101, first cavity; 102, second cavity; 103, middle cavity; 104, lower cavity; 105, first connection port; 106, second connection port; 107, first connection pipe; 108, second connection pipe; 11, third connection pipe; 12, fourth connection pipe; 13, steam inlet of the steam heater; 14, steam outlet of the steam heater; 15, left flue gas pipe; 2, first burner; 31, first partition board; 32, second partition board; 33, third partition board; 34, first heat exchange pipe; 35, second heat exchange pipe; 36, steam connection pipe; 41, right flue gas pipe; 42, heat exchanger; 43, induced draft fan; 51. Inner furnace body; 511. Feed inlet; 512. Syngas outlet; 513. Frustum section; 514. Gasification reaction chamber; 515. Compartment; 52. Outer furnace body; 521. Gas outlet; 522. Gas inlet; 53. Hollow interlayer; 54. First refractory layer; 55. Refractory brick layer; 56. Metal shell; 57. Ash hopper; 58. Second refractory layer; 61. Level gauge; 62. Temperature sensor; 63. Second burner; 64. Spiral blade; 65. Inlet pipe; 66. Outlet pipe; 67. Feed auger; 68. Syngas pipeline; 71. Cooling pipeline; 711. Inlet end of water; 712. Outlet end of water; 72. First valve; 73. Transition section; 74. Second valve; 81. Refractory cement casting partition; 811. Installation channel; 82. Air cap structure; 821. Air outlet hole; 822. Air inlet hole; 823. Conical hole structure; 83. Annular pipeline; 84. Steam inlet pipe; 85. Ash discharge channel. Detailed implementation mode

[0037] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and preferred embodiments.

[0038] In the following, example embodiments will be described more fully with reference to the accompanying drawings. However, the example embodiments may be embodied in different forms and should not be construed as limited to the embodiments set forth herein. On the contrary, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

[0039] In the case of no conflict, each embodiment of the present disclosure and each feature in the embodiment may be combined with each other.

[0040] In the description of the present invention, it should be noted that, unless otherwise clearly defined and limited, the terms "installation", "connection", "connection", "setting" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a direct connection, or an indirect connection through an intermediate medium, or the internal connection of two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention may be understood according to specific situations.

[0041] In addition, for the convenience of description, the present invention defines the direction of the left hand side shown as "left", and the direction of the right hand side shown as "right". The terms "left" and "right" involved in the present invention shall be subject to the above definitions. Figure 2 Figure 2 The terms "left" and "right" involved in the present invention shall be subject to the above definitions. Embodiment 1

[0042] The biomass-to-syngas production line described in this embodiment includes a steam boiler 800, a steam heater 500, and a gasification reactor 400.

[0043] Among them, the steam heater 500 has two heat exchange channels: a high-temperature gas heat exchange channel and a steam heat exchange channel. The positions of the high-temperature gas heat exchange channel and the steam heat exchange channel are arranged such that the steam entering the steam heat exchange channel can indirectly exchange heat with the high-temperature gas entering the high-temperature gas heat exchange channel.

[0044] Among them, the structure of the gasification reactor 400 described in this embodiment includes a reaction furnace, as Figure 7 shown. The reaction furnace includes an inner furnace body 51 and an outer furnace body 52. A closed hollow interlayer 53 is formed between the inner furnace body 51 and the outer furnace body 52. An air outlet 521 communicating with the hollow interlayer 53 is provided on the outer side wall of the top of the outer furnace body 52, and an air outlet pipe 66 is hermetically connected to the air outlet 521. An air inlet 522 communicating with the hollow interlayer 53 is provided on the outer side wall of the bottom of the outer furnace body 52, and an air inlet pipe 65 is hermetically connected to the air inlet 522.

[0045] As Figure 1 shown, in this embodiment, a feed inlet 511 communicating with the furnace chamber of the inner furnace body 51 is provided on the outer side wall of the top of the inner furnace body 51, and the feed inlet 511 is hermetically connected to the outlet of the feed auger 67. A syngas outlet 512 communicating with the furnace chamber of the inner furnace body 51 is provided on the top of the inner furnace body 51, and a syngas delivery pipe 68 is hermetically connected to the syngas outlet 512. The output syngas has a relatively high temperature, so the syngas delivery pipe 68 is connected to the water cooling device 1000. The water cooling device 1000 may include a post-stage heat exchanger and a post-stage dust collector. The syngas is output after being cooled by the post-stage heat exchanger and dust removed by the post-stage dust collector. Of course, the water cooling device 1000 can also adopt other structural forms according to actual requirements, and the temperature of the syngas is reduced to about 200 °C through the water cooling device 1000.

[0046] As Figure 7 、 Figure 8 and Figure 9 shown, in this embodiment, a refractory cement casting partition layer 81 is provided in the lower section of the furnace chamber of the inner furnace body 51. The refractory cement casting partition layer 81 divides the furnace chamber of the inner furnace body 51 into two upper and lower chambers: a gasification reaction chamber 514 and a partition chamber 515.

[0047] In the middle of the refractory cement casting partition layer 81, there is an ash discharge channel 85 penetrating up and down; on the refractory cement casting partition layer 81, a number of installation channels 811 penetrating up and down are evenly spaced. In each installation channel 811, a wind cap structure 82 is correspondingly arranged, and the parts where the air outlet holes 821 on the wind cap structure 82 are located extend above the corresponding installation channel 811. The specific structure of the wind cap structure 82 is: the body is a hollow pipe, the top of the hollow pipe is closed, and a number of air outlet holes 821 are circumferentially arranged on the side wall of the top of the hollow pipe. The bottom end of the hollow pipe is open to form an air inlet hole 822 communicating with the hollow channel in the middle of the hollow pipe. In order to make the air flow more evenly dispersed and dispersed from each air outlet hole 821, the top end of the hollow channel is set as a conical hole structure 823.

[0048] In the partition chamber 515, an annular pipeline 83 is arranged. A first connection hole and a number of second connection holes are opened on the annular pipeline 83. At the first connection hole, a steam inlet pipe 84 is hermetically connected. The steam inlet pipe 84 hermetically passes through the through hole on the reaction furnace and extends outside the reaction furnace; each second connection hole corresponds to the position of the air inlet hole 822 at the bottom of each wind cap structure 82 one by one, and the air inlet hole 822 at the bottom of each wind cap structure 82 is hermetically connected to the corresponding second connection hole.

[0049] As Figure 1 shown, in this embodiment, the bottom of the inner furnace body 51 is open to form an open mouth. An ash discharge hopper 57 is hermetically installed at the open mouth, and an ash discharge valve is installed at the ash discharge port of the ash discharge hopper 57.

[0050] The reaction furnace is wrapped with a refractory layer. The air outlet pipe 66, the air inlet pipe 65, the steam inlet pipe 84, and the feed inlet of the feed auger 67 all extend outside the refractory layer.

[0051] The boiler steam outlet of the steam boiler 800 is connected to the steam inlet of the steam heat exchange channel in the steam heater 500 through a first connection pipeline. The steam outlet of the steam heat exchange channel in the steam heater 500 is connected to the steam inlet pipe of the gasification reactor 400 through a second connection pipeline.

[0052] The high-temperature steam entering the hollow interlayer 53 of the gasification reactor 400 comes from the steam heater 500. The initial steam that needs to be heated by the steam heater 500 comes from the steam boiler 800. The steam generated by the steam boiler 800 usually has a temperature of about 150°C. This steam is introduced into the steam heat exchange channel in the steam heater 500, and high-temperature gas (the temperature of the high-temperature gas is usually about 1000°C) is introduced into the high-temperature gas heat exchange channel. The temperature of the steam at about 150°C introduced into the steam heater 500 is raised to more than 800°C through an indirect heat exchange method.

[0053] The high-temperature steam (with a temperature above 800 °C) output from the steam heater 500 enters each wind cap structure 82 through the second connection pipeline, the steam inlet pipe 84, and the annular pipeline 83, and then enters the gasification reaction chamber 514 through each air outlet hole 821 on each wind cap structure 82. Here, the wind cap structure 82 is provided to enable the high-temperature steam to be more evenly distributed in the gasification reaction chamber 514, so that the materials entering the gasification reaction chamber 514 can come into full contact with the high-temperature steam to undergo a gasification reaction, improving the gasification reaction efficiency. With the addition of the high-temperature gas auxiliary heating through the above-mentioned hollow sandwich layer 53, the gasification reaction efficiency is further improved.

[0054] Materials such as biomass raw materials and carbon made from biomass raw materials enter the furnace cavity of the inner furnace body 51 through the feeding auger 67, and come into contact with the high-temperature steam entering the gasification reaction chamber 514 through each air outlet hole 821 on each wind cap structure 82. The materials move from top to bottom, and the high-temperature steam moves from bottom to top. The ash after the gasification reaction falls downward through the ash discharge channel 85, and the syngas after the gasification reaction rises and is output outside the reaction furnace through the syngas transmission pipeline 68.

[0055] The method for preparing syngas from biomass uses the biomass-to-syngas production line described in this embodiment. The method for preparing syngas from biomass is as follows: (1) Prepare high-temperature steam using the steam heater 500: Continuously introduce high-temperature gas into the high-temperature gas heat exchange channel of the steam heater 500. The temperature of the high-temperature gas is greater than 900 °C. After the high-temperature gas is introduced for 2 - 5 minutes, while the high-temperature gas is continuously introduced, continuously introduce steam into the steam heat exchange channel of the steam heater 500 through the steam boiler 800. The temperature of the steam is greater than 100 °C. The heat exchange path lengths of the high-temperature gas heat exchange channel and the steam heat exchange channel are ensured so that the temperature of the high-temperature steam output from the steam heat exchange channel is greater than 800 °C; (2) Prepare syngas using the gasification reactor 400: Continuously introduce materials into the gasification reaction chamber 514 of the gasification reactor 400 through the feeding auger 300. The materials move from top to bottom. The materials are biomass raw materials or biochar, with a length less than 30 mm and a thickness less than 10 mm, and the material feeding speed is 200 ± 10 kg / hour. When the material level in the gasification reaction chamber 514 reaches the set position, while the materials are continuously introduced, introduce high-temperature steam into the gasification reaction chamber 514 through the steam heater 500, the steam inlet pipe 84, and each wind cap structure 82. The high-temperature steam flows from bottom to top, and the flow rate of the high-temperature steam is matched with the feeding amount at a ratio of 1:1.

[0056] Among them, the gasification reactor in the above production line has the advantages of high gasification efficiency, basically no tar residue, and basically no residual carbon residue. The syngas produced by using this gasification reactor can be directly synthesized into green methanol without adding other substances, and can also be used for hydrogen production.

[0057] For the syngas obtained by using the above method for preparing syngas from biomass, the hydrogen content in the syngas can generally reach 40-70%, and the carbon monoxide content can generally reach 20-30%. This equipment has high hydrogen gasification efficiency and economic value, and the proportion of each component of the syngas can be easily adjusted, which is suitable for further processing to synthesize green methane or directly used for hydrogen production.

[0058] Example 2 The production line for preparing syngas from biomass described in this example includes: a steam boiler 800, a steam heater 500, and a gasification reactor 400.

[0059] Among them, the structure of the steam heater 500 described in this example includes: a heating furnace body 1, as Figure 2 and Figure 3 shown. The furnace cavity of the heating furnace body 1 is sequentially divided into several independent cavity units 10 from left to right. A more optimal solution is that the space occupied by each cavity unit 10 is equal. The number of the cavity units 10 is usually between 4 and 6. The actual number of the cavity units 10 is determined according to the size of the heating furnace body 1, the pipe diameters and quantities of the first heating tubes 34 and the second heating tubes 35 in the cavity units 10, the required steam temperature requirements, etc.

[0060] Among them, the structure inside each cavity unit 10 is: as Figure 3 , Figure 4 , Figure 5 and Figure 6 shown. In the cavity unit 10, a first partition plate 31 and a second partition plate 32 are arranged at intervals from top to bottom. The cavity unit 10 is divided into an upper cavity, a middle cavity 103, and a lower cavity 104 that are independent of each other from top to bottom through the first partition plate 31 and the second partition plate 32. A third partition plate 33 is arranged in the upper cavity, and the upper cavity is divided into a first cavity 101 and a second cavity 102 from left to right through the third partition plate 33. A more optimal solution is that the space occupied by the first cavity 101 and the second cavity 102 is equal.

[0061] As Figure 3As shown, a first connection port 105 communicating with the first cavity 101 is provided at the top of the heating furnace body 1, and the first cavity 101 communicates with the lower cavity 104 through a number of first heat exchange tubes 34 disposed in the middle cavity 103; a second connection port 106 communicating with the second cavity 102 is provided at the top of the heating furnace body 1, and the second cavity 102 communicates with the lower cavity 104 through a number of second heat exchange tubes 35 disposed in the middle cavity 103.

[0062] The tops of each of the first heat exchange tubes 34 and each of the second heat exchange tubes 35 are hermetically inserted through the respective upper mounting holes on the first partition plate 31, so that each of the first heat exchange tubes 34 communicates with the first cavity 101, and each of the second heat exchange tubes 35 communicates with the second cavity 102. The bottoms of each of the first heat exchange tubes 34 and each of the second heat exchange tubes 35 are hermetically inserted through the respective lower mounting holes on the second partition plate 32, so that each of the first heat exchange tubes 34 and each of the second heat exchange tubes 35 communicate with the lower cavity 104.

[0063] The first connection port 105 in each cavity unit 10 is communicated with the second connection port 106 in the cavity unit 10 adjacent to the left of this cavity unit 10 through a steam connection pipe 36; each of the first cavities 101, each of the second cavities 102, each of the steam connection pipes 36, each of the first heat exchange tubes 34, each of the second heat exchange tubes 35, and each of the lower cavities 104 form a steam heat exchange channel for steam to flow in a serpentine path; the first connection port 105 in the cavity unit 10 at the leftmost end is the steam outlet 14 of the steam heater, and the second connection port 106 in the cavity unit 100 at the rightmost end is the steam inlet 13 of the steam heater, as Figure 2 shown.

[0064] The middle cavity 103 in each cavity unit 10 penetrates from left to right, so that the middle cavities 103 in all cavity units 10 communicate to form a high-temperature gas heat exchange channel for gas to pass through; an air inlet communicating with the high-temperature gas heat exchange channel is provided at the left end of the heating furnace body 1, and the air inlet is the gas inlet of the high-temperature gas heat exchange channel, and an air outlet communicating with the high-temperature gas heat exchange channel is provided at the right end of the heating furnace body 1, and the air outlet is the gas outlet of the high-temperature gas heat exchange channel.

[0065] The flow direction of the high-temperature gas in the steam heater 500 is: the high-temperature gas enters the high-temperature gas heat exchange channel from the gas inlet and flows from left to right. During the flow of the high-temperature gas, it indirectly exchanges heat with the steam in each of the first heat exchange tubes 34 and each of the second heat exchange tubes 35 passing through, and then flows out from the gas outlet after releasing heat; The flow direction of steam in the steam heater 500 is as follows: The steam enters the heating furnace body 1 through the steam inlet 13, first enters the cavity unit at the rightmost end, and successively flows through the second cavity in the rightmost cavity unit, each second heat exchange tube, the lower cavity, each first heat exchange tube, and the first cavity, and then flows leftward into the adjacent cavity unit. After flowing through the second cavity, each second heat exchange tube, the lower cavity, each first heat exchange tube, and the first cavity in this cavity unit, it continues to flow leftward in a snake-like direction in the same flow direction and finally flows out from the steam outlet 14; during the flow of the steam, the steam flowing through each first heat exchange tube 34 and each second heat exchange tube 35 exchanges heat indirectly with the high-temperature gas in the high-temperature gas heat exchange channel outside the tube and absorbs heat.

[0066] Among them, the structure of the gasification reactor 400 described in this embodiment includes: a reaction furnace, as Figure 7 shown, the reaction furnace includes an inner furnace body 51 and an outer furnace body 52, and a closed hollow interlayer 53 is formed between the inner furnace body 51 and the outer furnace body 52. An air outlet 521 communicating with the hollow interlayer 53 is opened on the outer side wall of the top of the outer furnace body 52, and an air outlet pipe 66 is hermetically connected to the air outlet 521; an air inlet 522 communicating with the hollow interlayer 53 is opened on the outer side wall of the bottom of the outer furnace body 52, and an air inlet pipe 65 is hermetically connected to the air inlet 522.

[0067] As Figure 1 shown, in this embodiment, a feed inlet 511 communicating with the furnace cavity of the inner furnace body 51 is opened on the outer side wall of the top of the inner furnace body 51, and the feed inlet 511 is hermetically connected to the outlet of the feed auger 67; a syngas outlet 512 communicating with the furnace cavity of the inner furnace body 51 is opened at the top of the inner furnace body 51, and a syngas delivery pipe 68 is hermetically connected to the syngas outlet 512. The output syngas has a relatively high temperature, so the syngas outlet 68 is sequentially connected to the water cooling device 1000 through the syngas delivery pipe 68. The water cooling device 1000 may include a post-heat exchanger and a post-dust collector, and the syngas is output after being cooled by the post-heat exchanger and dust removed by the post-dust collector.

[0068] As Figure 7 、 Figure 8 and Figure 9 shown, in this embodiment, a refractory cement casting partition layer 81 is provided in the lower section of the furnace cavity of the inner furnace body 51, and the refractory cement casting partition layer 81 divides the furnace cavity of the inner furnace body 51 into two upper and lower chambers: a gasification reaction chamber 514 and a partition chamber 515.

[0069] An ash discharge channel 85 penetrating up and down is formed in the middle of the refractory cement casting partition layer 81; a number of installation channels 811 penetrating up and down are evenly spaced on the refractory cement casting partition layer 81, and a wind cap structure 82 is correspondingly arranged in each installation channel 811, and the parts where the air outlet holes 821 on the wind cap structure 82 are located extend above the corresponding installation channels 811.

[0070] An annular pipeline 83 is arranged in the partition chamber 515, a first connection hole and a number of second connection holes are formed in the annular pipeline 83, a steam inlet pipe 84 is hermetically connected at the first connection hole, and the steam inlet pipe 84 hermetically passes through a through hole on the reaction furnace and extends outside the reaction furnace; each second connection hole corresponds to the position of the air inlet hole 822 at the bottom of each wind cap structure 82 one by one, and the air inlet hole 822 at the bottom of each wind cap structure 82 is hermetically connected to the corresponding second connection hole.

[0071] As Figure 1 shown, in this embodiment, the bottom of the inner furnace body 51 is open to form an open opening, an ash discharge hopper 57 is hermetically installed at the open opening, and an ash discharge valve is installed at the ash discharge port of the ash discharge hopper 57.

[0072] The reaction furnace is wrapped with a refractory layer, and the air outlet pipe 66, the air inlet pipe 65, the steam inlet pipe 84, and the feed inlet of the feed auger 67 all extend outside the refractory layer.

[0073] The boiler steam outlet of the steam boiler 800 is connected to the steam inlet of the steam heater 500 through a first connection pipeline, and the steam outlet of the steam heater 500 is connected to the steam inlet pipe 84 of the gasification reactor 400 through a second connection pipeline.

[0074] The high-temperature steam entering the hollow interlayer 53 of the gasification reactor 400 comes from the steam heater 500. The initial steam that needs to be heated by the steam heater 500 comes from the steam boiler 800. The steam generated by the steam boiler 800 usually has a temperature of about 150 °C. This steam is introduced into the steam inlet 13 of the steam heater, enters the second cavity 102 in the cavity unit 10 at the rightmost end through the steam inlet 13 of the steam heater, and successively flows through each second heat exchange tube 35, the lower cavity 103, each first heat exchange tube 34, and the first cavity 101 in this cavity unit 10, and then flows into the cavity unit 10 adjacent to the left side of this cavity unit 10. The steam flow path is a serpentine path.

[0075] High-temperature gas (the temperature of the high-temperature gas is usually around 1000 °C) enters the middle cavity 103 in the cavity unit 10 at the leftmost end from the gas inlet, and sequentially passes through the middle cavities 103 in each cavity unit 10 from left to right and then flows out from the gas outlet. During this process, the high-temperature gas exchanges heat indirectly with the steam in each first heat exchange tube 34 and each second heat exchange tube 35 that it flows through, and releases heat.

[0076] During the flow of the steam and the high-temperature gas, the steam in each first heat exchange tube 34 and each second heat exchange tube 35 exchanges heat indirectly with the high-temperature gas outside the tubes, absorbs heat and then is output. The output steam temperature can reach over 800 °C, meeting the steam temperature required by the gasification reactor 400. The steam flow path is designed as a serpentine path, which can increase the heat exchange path, thereby improving the heat exchange efficiency. The high-temperature steam output from the steam heater 500 after heat exchange usually has a temperature of over 800 °C.

[0077] The high-temperature steam (with a temperature of over 800 °C) output from the gas outlet of the steam heater 500 enters each air cap structure 82 through the second connecting pipeline, the steam inlet pipe 84, and the annular pipeline 83, and then enters the gasification reaction chamber 514 through each air outlet hole 821 on each air cap structure 82. The air cap structure 82 is provided here to enable the high-temperature steam to be more evenly distributed in the gasification reaction chamber 514, so that the materials entering the gasification reaction chamber 514 can fully contact the high-temperature steam to undergo a gasification reaction, improving the gasification reaction efficiency. With the above-mentioned high-temperature gas introduced into the hollow interlayer 53 for auxiliary heating, the gasification reaction efficiency is further improved.

[0078] The method for preparing synthesis gas from biomass uses the production line for preparing synthesis gas from biomass described in this embodiment. The method for preparing synthesis gas from biomass is as follows: (1) Prepare high-temperature steam using the steam heater 500: Continuously introduce high-temperature gas into the high-temperature gas heat exchange channel of the steam heater 500. The temperature of the high-temperature gas is greater than 900 °C. After the high-temperature gas is introduced for 2 - 5 minutes, while the high-temperature gas is continuously introduced, continuously introduce steam into the steam heat exchange channel of the steam heater 500 through the steam boiler 800. The temperature of the steam is greater than 100 °C. The heat exchange path lengths of the high-temperature gas heat exchange channel and the steam heat exchange channel are ensured so that the temperature of the high-temperature steam output from the steam heat exchange channel is greater than 800 °C; (2) Prepare synthesis gas using the gasification reactor 400: The material is continuously fed into the gasification reaction chamber 514 of the gasification reactor 400 through the feeding auger 300. The material moves from top to bottom. The material is biomass raw material or biochar, with a length less than 30 mm and a thickness less than 10 mm, and the feeding speed of the material is 200 ± 10 kg / h. When the material level in the gasification reaction chamber 514 reaches the set position, while the material is continuously fed, high-temperature steam is fed into the gasification reaction chamber 514 through the steam heater 500, the steam inlet pipe 84, and each air cap structure 82. The high-temperature steam flows from bottom to top, and the flow rate of the high-temperature steam is in a 1:1 ratio with the feeding amount.

[0079] The steam heater in the above production line has the advantages of simple and compact structure, simple operation, low energy consumption, economic and environmental protection, and can efficiently and economically produce high-temperature steam with a temperature above 800 °C. The gasification reactor in the above production line has the advantages of high gasification efficiency, basically no tar residue, and basically no residual carbon residue. The syngas produced by using this gasification reactor can be directly synthesized into green methanol without adding other substances. In addition, it can also be used for hydrogen production.

[0080] For the syngas obtained by using the above preparation method for preparing syngas from biomass, the hydrogen content in the syngas can generally reach 40-70%, and the carbon monoxide content can generally reach 20-30%. This equipment has high gasification efficiency and economic value for hydrogen production, and the proportion of each component of the syngas can be easily adjusted, which is suitable for further processing and synthesizing green methane, or directly used for hydrogen production.

[0081] Example 3 The gasification reaction using charcoal has better effect than using biomass raw material for gasification reaction, and the obtained syngas is purer, and tar and residues are less likely to be generated. Therefore, in this example, on the basis of the structure described in Example 2, a biomass carbonization furnace 100 is added. An outlet auger 200 is arranged at the biochar outlet of the biomass carbonization furnace 100, and the outlet of the outlet auger 200 is connected to the inlet of the feeding auger 300. The biomass raw material is carbonized in the biomass carbonization furnace 100 to obtain biochar, and the biochar enters the gasification reactor 400 through the outlet auger 200 and the feeding auger 300 for gasification reaction.

[0082] The steam boiler 800 usually uses coal or the like as fuel supply. Considering the green energy problem in this scheme, the first biomass gasification furnace 900 is adopted. The combustible gas outlet of the first biomass gasification furnace 900 is connected to the fuel supply inlet of the steam boiler 800 through the third connecting pipeline. The biomass raw material is gasified in the first biomass gasification furnace 900 to obtain combustible gas, and the combustible gas is transported to the steam boiler 800 as the fuel of the steam boiler 800.

[0083] In addition, the high-temperature gas in the steam heater 500 is sourced from high-temperature flue gas. A combustion chamber 600 is provided at the gas inlet of the steam heater 500. The flue gas outlet of the combustion chamber 600 is connected to the gas inlet of the steam heater 500 through the left flue gas pipeline 15. The combustible substance in the combustion chamber 600 can be combustible gas or combustible solid materials. Here, considering economic and environmental protection, the second biomass gasifier 700 is adopted. The combustible gas outlet of the second biomass gasifier 700 is connected to the air inlet of the first burner 2 provided on the combustion chamber 600 through the fourth connecting pipeline, as Figure 1 and Figure 2 shown. The second biomass gasifier 700 gasifies the biomass raw material to produce combustible gas, and then the combustible gas produced by biomass gasification is introduced into the first burner 2 for combustion to generate high-temperature gas.

[0084] The above-mentioned steam heater 500 utilizes the steam produced by the steam boiler 800 (the temperature of this steam is usually around 150 °C) and the combustible gas produced by biomass gasification. By burning the combustible gas to generate high-temperature flue gas to reheat the steam produced by the steam boiler 800, the steam temperature is thus increased to above 800 °C.

[0085] The flue gas flowing out from the gas outlet of the heating furnace body 1 needs to be treated. A heat exchanger 42 and a induced draft fan 43 are provided. The gas outlet of the heating furnace body 1 is sequentially connected to the air inlets of the heat exchanger 42 and the induced draft fan 43 through the right flue gas pipeline 41.

[0086] The preparation method of the biomass to produce synthesis gas adopts the biomass to produce synthesis gas production line described in this embodiment. The preparation method of the biomass to produce synthesis gas is as follows: (1) Using the steam heater 500 to prepare high-temperature steam: Continuously introduce high-temperature gas into the high-temperature gas heat exchange channel of the steam heater 500. The temperature of the high-temperature gas is greater than 900 °C. After the high-temperature gas is introduced for 2 - 5 minutes, while the high-temperature gas is continuously introduced, continuously introduce steam into the steam heat exchange channel of the steam heater 500 through the steam boiler 800. The temperature of the steam is greater than 100 °C. The heat exchange path lengths of the high-temperature gas heat exchange channel and the steam heat exchange channel ensure that the high-temperature steam output from the steam heat exchange channel has a temperature greater than 800 °C; Among them, the high-temperature gas introduced into the high-temperature gas heat exchange channel of the steam heater 500 is high-temperature flue gas, which is obtained by burning the combustible gas gasified by the second biomass gasifier in the combustion chamber. The temperature of the high-temperature flue gas is 1000 - 1200 °C; Among them, the fuel of the steam boiler 800 is sourced from the combustible gas gasified by the first biomass gasifier 900. The steam temperature produced by the steam boiler 800 is 120 - 160 °C; (2) Prepare syngas using a gasification reactor 400: Continuously feed materials into the gasification reaction chamber 514 of the gasification reactor 400 through a feed auger 300. The materials move from top to bottom. The materials are biomass raw materials or biochar, with a length less than 30 mm and a thickness less than 10 mm. The material feeding speed is 200 ± 10 kg / h. When the material level in the gasification reaction chamber 514 reaches the set position, while continuously feeding the materials, high-temperature steam is introduced into the gasification reaction chamber 514 through a steam heater 500, a steam inlet pipe 84, and each air cap structure 82. The high-temperature steam flows from bottom to top, and the flow rate of the high-temperature steam is in a 1:1 ratio with the feeding amount.

[0087] Among them, the material is biochar, and the biochar is sourced from a biomass carbonization furnace 100. The biochar produced by the biomass carbonization furnace 100 enters the gasification reaction chamber 514 of the gasification reactor 400 through a discharge auger 200 and a feed auger 300, and moves from top to bottom. Among them, the high-temperature gas introduced into the hollow sandwich layer 53 of the gasification reactor 400 is high-temperature flue gas, which is obtained by burning 8% - 15% of the syngas. The temperature of the high-temperature flue gas is 1000 - 1200 °C.

[0088] A more preferred solution is that the furnace cavity of the heating furnace body 1 is designed in a cuboid shape; each first connection port 105 corresponding to each cavity unit 10 is connected to the first cavity 101 of this cavity unit 10 through a frustum-shaped first connection pipe 107; each second connection port 106 corresponding to each cavity unit 10 is connected to the second cavity 102 of this cavity unit 10 through a frustum-shaped second connection pipe 108, as Figure 3 shown.

[0089] A more preferred solution is that the gas inlet is connected to the middle cavity 103 in the cavity unit 10 at the leftmost end through a frustum-shaped third connection pipe 11; the gas outlet is connected to the middle cavity 103 in the cavity unit 10 at the rightmost end through a frustum-shaped fourth connection pipe 12, as Figure 2 、 Figure 4 and Figure 5 shown.

[0090] In this embodiment, the partition walls that divide the heating furnace body 1 into several independent cavity units 10 can be two partition walls. One partition wall divides between two adjacent upper cavities, and the other partition wall divides between two adjacent lower cavities. The partition wall can also be designed as a whole, with a communication hole left in the middle to connect two adjacent middle cavities.

[0091] As Figure 1 and Figure 2As shown in the figure, the positional relationship among the first partition plate 31, the second partition plate 32, the third partition plate 33, each first heat exchange tube 34, and each second heat exchange tube 35 in each cavity unit 10 is preferably as follows: the first partition plate 31 and the second partition plate 32 are arranged horizontally; the third partition plate 33 is perpendicular to the first partition plate 31; the axes of each first heat exchange tube 34 are all perpendicular to the first partition plate 31, and the axes of each second heat exchange tube 35 are all perpendicular to the first partition plate 31.

[0092] Each first heat exchange tube 34 in each cavity unit 10 is evenly spaced, and each second heat exchange tube 35 in each cavity unit 10 is evenly spaced; the number of first heat exchange tubes 34 in each cavity unit 10 is the same as the number of second heat exchange tubes 35. A more preferred solution is that each first heat exchange tube 34 and each second heat exchange tube 35 both adopt a circular tube structure with the same pore diameter, such as Figure 5 and Figure 6 shown.

[0093] Among them, the first partition plate 31 in each cavity unit 10 can be an independent plate, or it can be a part of a whole plate, and all the first partition plates 31 form a whole plate. The same applies to the second partition plate 32.

[0094] High-temperature gas is used to be introduced into the hollow interlayer 53 of the gasification reactor 400 to achieve auxiliary heating of the inner furnace body 51, ensure the gasification reaction temperature in the furnace cavity of the inner furnace body 51, and improve the gasification efficiency. A more preferred solution is that a number of spiral blades 64 are provided in the hollow interlayer 53, and each spiral blade 64 is evenly spaced along a spiral line trajectory that spirals upward from bottom to top. Such a setting can increase the path of the high-temperature gas, improve the heat exchange efficiency, and further ensure the gasification efficiency.

[0095] The high-temperature gas in the gasification reactor 400 also comes from high-temperature flue gas. The synthesis gas pipeline 68 of the gasification reactor 400 is respectively connected to the synthesis gas supply pipeline and the fifth connection pipeline. The fifth connection pipeline is connected to the second burner 63 in the intake pipe provided on the gasification reactor 400. The synthesis gas supply pipeline is successively connected to the subsequent heat exchanger and the subsequent dust collector, and is output after being cooled by the subsequent heat exchanger and dust removed by the subsequent dust collector. At this time, the high-temperature gas introduced into the hollow interlayer 53 of the gasification reactor 400 is obtained by burning a part of the synthesis gas generated by the reaction of the gasification reactor 400. For example, 10% of the synthesis gas is introduced into the second burner 63 through the fifth connection pipeline. The selection ratio can be controlled by the opening of the valve installed on the fifth connection pipeline. The synthesis gas introduced into the second burner 63 burns to generate high-temperature flue gas. The high-temperature flue gas enters the hollow interlayer 53 and spirals upward under the guidance of each spiral blade 64, and finally is discharged from the air outlet pipe 66.

[0096] In addition, in order to prevent outside air from entering the ash discharge hopper 57 through the ash discharge valve and then flowing upward into the gasification reaction chamber 514, which may affect the gasification reaction, in this embodiment, the above ash discharge valve is arranged in a double-valve structure, that is, it includes: a first valve 72, a second valve 74, and a transition section 73 connecting the outlet of the first valve 72 and the inlet of the second valve 74. When ash discharge is required, first open the first valve 72 while keeping the second valve 74 closed. The ash drops into the transition section 73, and then close the first valve 72 and open the second valve 74, and the ash in the transition section 73 can be cleared out.

[0097] A more preferred solution in this embodiment is that the top of the inner furnace body 51 protrudes upward outside the outer furnace body 52, and the part of the inner furnace body 51 protruding outside the outer furnace body 52 is a frustum-shaped frustum section 513. At this time, the syngas outlet 512 is located on the top surface of the frustum section 513; the feed inlet 511 is located on the side wall of the frustum section 513.

[0098] The entire reaction furnace reacts at a high temperature, so a refractory layer needs to be wrapped outside the reaction furnace. Among them, the refractory layer wrapped outside the frustum section 513 is a refractory layer obtained by casting refractory cement - the first refractory layer 54.

[0099] The refractory layer wrapped outside the outer furnace body 52 is a refractory brick layer 55, and a metal shell 56 with several claw nails inside is covered outside the refractory brick layer 55. In the actual manufacturing process, a layer of thermal insulation cotton can also be added between the refractory brick layer 55 and the metal shell 56. The refractory layer wrapped outside the ash discharge hopper 57 is a refractory layer obtained by casting refractory cement - the second refractory layer 58.

[0100] The temperature of the ash generated by gasification is relatively high. Therefore, in this embodiment, a cooling pipeline 71 is arranged in the inner cavity of the ash discharge hopper 57. The water inlet end 711 of the cooling pipeline 71 passes through the first connection through hole on the ash discharge hopper 57 and the second connection through hole on the second refractory layer 58 in a sealed manner and then extends outside the second refractory layer 58. The water outlet end 712 of the cooling pipeline 71 passes through the third connection through hole on the ash discharge hopper 57 and the fourth connection through hole on the second refractory layer 58 in a sealed manner and then extends outside the second refractory layer 58. The cooling medium enters the cooling pipeline 71 through the water inlet end 711 of the cooling pipeline 71 to cool the ash in the ash discharge hopper 57, and then flows out through the water outlet end 712 of the cooling pipeline 71.

[0101] To facilitate an intuitive understanding of the material level within the inner furnace body 51 and the temperature within the furnace cavity of the inner furnace body 51, in this embodiment, a level gauge 61 for measuring the material level of the material entering the furnace cavity of the inner furnace body 51 is provided on the reaction furnace. During the process of continuously feeding material into the gasification reaction chamber 514 through the feed auger 300, the set position of the material within the gasification reaction chamber 514 is determined by the level gauge 61; a temperature sensor 62 for measuring the temperature within the furnace cavity of the inner furnace body 51 is provided on the reaction furnace.

[0102] The steam heater in the above production line has the advantages of simple and compact structure, simple operation, low energy consumption, economic and environmental protection, and can efficiently and economically produce high-temperature steam with a temperature above 800°C; the gasification reactor in the above production line has the advantages of high gasification efficiency, basically no tar residue, and basically no residual carbon residue; the syngas produced by using this gasification reactor can directly synthesize green methanol without adding other substances, and can also be used for hydrogen production.

[0103] In addition, the fuel source of the steam boiler 800 and the fuel source of the high-temperature flue gas in the steam heater 500 both come from the combustible gas generated by the gasification of the biomass gasifier, the fuel of the high-temperature flue gas in the gasification reactor 400 comes from a part of the syngas in the gasification reaction, and the raw materials in the gasification reactor 400 come from the biochar produced by the carbonization of the biomass carbonization furnace 100. The entire production line uses green and environmentally friendly biomass raw materials, which are economic, environmentally friendly and have low energy consumption.

[0104] For the syngas obtained by using the above method for preparing syngas from biomass, the hydrogen content in the syngas can generally reach 40 - 70%, and the carbon monoxide content can generally reach 20 - 30%. This equipment has high gasification efficiency and economic value for hydrogen production, and the proportion of each component of the syngas is convenient to adjust, which is suitable for further processing to synthesize green methane or directly used for hydrogen production.

[0105] The above description is only a preferred embodiment of the present invention, and does not impose any other form of limitation on the present invention. Any modification or equivalent change made based on the technical essence of the present invention still falls within the scope of protection required by the present invention.

Claims

1. A method for preparing syngas from biomass, which uses a production line for preparing syngas from biomass, and the production line includes: Steam boiler, characterized in that it further comprises: a steam heater and a gasification reactor; The steam heater has two heat exchange channels: a high-temperature gas heat exchange channel and a steam heat exchange channel. The positions of the high-temperature gas heat exchange channel and the steam heat exchange channel are arranged such that the steam entering the steam heat exchange channel can indirectly exchange heat with the high-temperature gas entering the high-temperature gas heat exchange channel; The structure of the gasification reactor includes: a reaction furnace composed of an inner furnace body and an outer furnace body. A closed hollow interlayer is formed between the inner furnace body and the outer furnace body; an air outlet pipe communicating with the hollow interlayer is provided on the outer side wall of the top of the outer furnace body; an air inlet pipe communicating with the hollow interlayer is provided on the outer side wall of the bottom of the outer furnace body; A feeding auger communicating with the furnace chamber of the inner furnace body is provided on the outer side wall of the top of the inner furnace body; a syngas conveying pipeline communicating with the furnace chamber of the inner furnace body is provided on the top of the inner furnace body; the bottom of the inner furnace body has an open opening communicating with the furnace chamber of the inner furnace body, and an ash discharge hopper is installed at the open opening, and an ash discharge valve is installed at the ash discharge port of the ash discharge hopper; A refractory cement casting partition layer is provided in the lower section of the furnace chamber of the inner furnace body. The refractory cement casting partition layer divides the furnace chamber of the inner furnace body into two upper and lower chambers: a gasification reaction chamber and a partition chamber; an ash discharge channel penetrating up and down is opened in the middle of the refractory cement casting partition layer; a number of installation channels penetrating up and down are evenly spaced on the refractory cement casting partition layer, and a wind cap structure is correspondingly arranged in each installation channel, and the parts where the air outlet holes on the wind cap structure are located extend above the corresponding installation channels; A ring pipeline is provided in the partition chamber. A first connection hole and a number of second connection holes are opened on the ring pipeline. A steam inlet pipe is hermetically connected at the first connection hole. The steam inlet pipe hermetically passes through a through hole on the reaction furnace and extends outside the reaction furnace; each second connection hole is respectively in one-to-one correspondence and matching with the air inlet holes at the bottoms of the respective wind cap structures, and the air inlet holes at the bottoms of the respective wind cap structures are hermetically connected to the corresponding second connection holes; The reaction furnace is wrapped with a refractory layer outside. The outlets of the air outlet pipe, the inlets of the air inlet pipe, the inlets of the steam inlet pipe, and the feeding ports of the feeding auger are all located outside the refractory layer; The steam outlet of the steam boiler is connected to the steam inlet of the steam heat exchange channel in the steam heater through a first connection pipeline. The steam outlet of the steam heat exchange channel in the steam heater is connected to the steam inlet pipe of the gasification reactor through a second connection pipeline; The preparation method for preparing syngas from biomass is as follows: (1) Using a steam heater to prepare high-temperature steam: Continuously introduce high-temperature gas into the high-temperature gas heat exchange channel of the steam heater. The temperature of the high-temperature gas is greater than 900 °C. After the high-temperature gas is introduced for 2 to 5 minutes, while the high-temperature gas is continuously introduced, continuously introduce steam into the steam heat exchange channel of the steam heater through the steam boiler. The temperature of the steam is greater than 100 °C; the heat exchange path lengths of the high-temperature gas heat exchange channel and the steam heat exchange channel ensure that the temperature of the high-temperature steam output from the steam heat exchange channel is greater than 800 °C; (2) Using a gasification reactor to prepare syngas: Materials are continuously fed into the gasification reaction chamber of the gasification reactor through a feeding auger. The materials move from top to bottom. The materials are biomass raw materials or biochar, with a length less than 30 mm and a thickness less than 10 mm. When the material level in the gasification reaction chamber reaches the set position, while the materials are continuously fed, high-temperature steam is introduced into the gasification reaction chamber through a steam heater, a steam inlet pipe, and each air cap structure. The high-temperature steam flows from bottom to top, and the flow rate of the high-temperature steam is in a 1:1 ratio with the feeding rate.

2. The preparation method of syngas prepared from biomass according to claim 1, characterized in that: It also includes: A biomass carbonization furnace, a first biomass gasification furnace, and a second biomass gasification furnace; A front auger is provided at the biochar outlet of the biomass carbonization furnace, and the discharge port of the front auger is connected to the feed port of the feeding auger; The combustible gas outlet of the first biomass gasification furnace is connected to the fuel supply inlet of the steam boiler through a third connecting pipeline; A combustion chamber is provided at the gas inlet of the high-temperature gas heat exchange channel in the steam heater. The combustible gas outlet of the second biomass gasification furnace is connected to a first burner provided on the combustion chamber through a fourth connecting pipeline; The syngas delivery pipeline of the gasification reactor is respectively connected to a syngas supply pipeline and a fifth connecting pipeline. The fifth connecting pipeline is connected to a second burner in the inlet pipe provided on the gasification reactor. A valve for controlling the amount of syngas transported to the second burner is provided on the fifth connecting pipeline. The syngas supply pipeline is connected to the air inlet of the water washing device; In the first step of the preparation method of preparing syngas from biomass, the high-temperature gas introduced into the high-temperature gas heat exchange channel of the steam heater is high-temperature flue gas, which is obtained by burning the combustible gas gasified by the second biomass gasification furnace in the combustion chamber. The temperature of the high-temperature flue gas is 1000 - 1200 °C; In the first step of the preparation method of preparing syngas from biomass, the fuel of the steam boiler comes from the combustible gas gasified by the first biomass gasification furnace, and the temperature of the steam generated by the steam boiler is 120 - 160 °C; In the second step of the preparation method of preparing syngas from biomass, the material is biochar, and the biochar comes from the biomass carbonization furnace; In the second step of the preparation method of preparing syngas from biomass, the high-temperature gas introduced into the hollow interlayer of the gasification reactor is high-temperature flue gas, which is obtained by burning 8% - 15% of the syngas. The temperature of the high-temperature flue gas is 1000 - 1200 °C.

3. The method for preparing syngas from biomass according to claim 1 or 2, characterized in that: The structure of the steam heater includes: a heating furnace body, and the furnace cavity of the heating furnace body is sequentially divided into several cavity units from left to right; The structure within each cavity unit is as follows: In the cavity unit, a first partition plate and a second partition plate are arranged at intervals from top to bottom. The cavity unit is divided into an upper cavity, a middle cavity, and a lower cavity from top to bottom by the first partition plate and the second partition plate. A third partition plate is arranged in the upper cavity, and the upper cavity is divided into a first cavity and a second cavity from left to right by the third partition plate. A first connection port communicating with the first cavity is arranged at the top of the heating furnace body, and the first cavity is communicated with the lower cavity through a number of first heat exchange tubes arranged in the middle cavity. A second connection port communicating with the second cavity is arranged at the top of the heating furnace body, and the second cavity is communicated with the lower cavity through a number of second heat exchange tubes arranged in the middle cavity. Each first connection port in each cavity unit is communicated with the second connection port in the cavity unit adjacent to the left side of this cavity unit through a steam connection pipe. Each first cavity, each second cavity, each steam connection pipe, each first heat exchange tube, each second heat exchange tube, and each lower cavity constitute a steam heat exchange channel for the steam to flow in a serpentine path. The first connection port in the cavity unit at the leftmost end is the steam outlet of the steam heat exchange channel, and the second connection port in the cavity unit at the rightmost end is the steam inlet of the steam heat exchange channel. The middle cavities in each cavity unit penetrate from left to right, so that the middle cavities in all cavity units are communicated to form a high-temperature gas heat exchange channel. An air inlet communicating with the high-temperature gas heat exchange channel is arranged at the left end of the heating furnace body, and the air inlet is the gas inlet of the high-temperature gas heat exchange channel. An air outlet communicating with the high-temperature gas heat exchange channel is arranged at the right end of the heating furnace body, and the air outlet is the gas outlet of the high-temperature gas heat exchange channel. The flow direction of the high-temperature gas in the steam heater is: The high-temperature gas enters the high-temperature gas heat exchange channel from the gas inlet and flows from left to right. During the flow of the high-temperature gas, it indirectly exchanges heat with the steam in each first heat exchange tube and each second heat exchange tube passing through it, and then flows out from the gas outlet after releasing heat. The flow direction of the steam in the steam heater is: The steam enters the heating furnace body through the steam inlet and first enters the cavity unit at the rightmost end. It sequentially flows through the second cavity, each second heat exchange tube, the lower cavity, each first heat exchange tube, and the first cavity in the cavity unit at the rightmost end, and then flows left into the adjacent cavity unit. After flowing through the second cavity, each second heat exchange tube, the lower cavity, each first heat exchange tube, and the first cavity in this cavity unit, it continues to flow left in the same flow direction in a serpentine direction and finally flows out from the steam outlet. During the flow of the steam, the steam in each first heat exchange tube and each second heat exchange tube exchanges heat indirectly with the high-temperature gas in the high-temperature gas heat exchange channel outside the tube and absorbs heat.

4. The preparation method of syngas prepared from biomass according to claim 3, wherein: The furnace cavity of the heating furnace body is in the shape of a cuboid; the first connection port corresponding to each cavity unit is communicated with the first cavity of the cavity unit through a frustum-shaped first connecting pipe; the second connection port corresponding to each cavity unit is communicated with the second cavity of the cavity unit through a frustum-shaped second connecting pipe; the gas inlet of the high-temperature gas heat exchange channel is communicated with the middle cavity in the leftmost cavity unit through a frustum-shaped third connecting pipe; the gas outlet of the high-temperature gas heat exchange channel is communicated with the middle cavity in the rightmost cavity unit through a frustum-shaped fourth connecting pipe; The third partition plate in each cavity unit evenly divides the upper cavity in the cavity unit, so that the spaces of the first cavity and the second cavity in the cavity unit are of the same size; The positional relationship among the first partition plate, the second partition plate, the third partition plate, each first heat exchange pipe, and each second heat exchange pipe in each cavity unit is as follows: the first partition plate and the second partition plate are arranged horizontally; the third partition plate is perpendicular to the first partition plate; the axes of each first heat exchange pipe are all perpendicular to the first partition plate, and the axes of each second heat exchange pipe are all perpendicular to the first partition plate; Each first heat exchange pipe in each cavity unit is evenly spaced, each second heat exchange pipe in each cavity unit is evenly spaced, and the number of first heat exchange pipes in each cavity unit is the same as the number of second heat exchange pipes.

5. The preparation method of syngas from biomass according to claim 3, characterized in that: It further includes: A heat exchanger and a draft fan, and the gas outlet of the high-temperature gas heat exchange channel is connected to the air inlets of the heat exchanger and the draft fan in sequence through a right flue gas pipeline.

6. The preparation method of syngas prepared from biomass according to claim 1, characterized in that: A number of spiral vanes are arranged in the hollow interlayer of the gasification reactor, and the spiral vanes are evenly spaced along a spiral line trajectory spiraling upward from bottom to top.

7. The method for preparing syngas from biomass according to claim 1 or 6, characterized in that: The top of the inner furnace body in the gasification reactor protrudes upward outside the outer furnace body, and the part of the inner furnace body protruding outside the outer furnace body is a frustum-shaped frustum section; the syngas conveying pipeline is located on the top surface of the frustum section; the feeding auger is located on the side wall of the frustum section.

8. The preparation method of syngas prepared from biomass according to claim 1 or 6, characterized in that: A cooling pipeline is arranged in the inner cavity of the ash hopper in the gasification reactor. The water inlet end of the cooling pipeline hermetically passes through the first connection through hole on the ash hopper and the second connection through hole on the refractory layer wrapped outside the ash hopper and then extends outside the refractory layer wrapped outside the ash hopper. The water outlet end of the cooling pipeline hermetically passes through the third connection through hole on the ash hopper and the fourth connection through hole on the refractory layer wrapped outside the ash hopper and then extends outside the refractory layer wrapped outside the ash hopper; The ash discharge valve is composed of a first valve, a second valve, and a transition section connecting the outlet of the first valve and the inlet of the second valve.

9. The preparation method of syngas prepared from biomass according to claim 7, characterized in that: The refractory layer wrapped outside the frustum section is a first refractory layer obtained by casting refractory cement; the refractory layer wrapped outside the outer furnace body is a refractory brick layer, and a metal outer shell with a number of claw nails inside is covered outside the refractory brick layer; the refractory layer wrapped outside the ash hopper is a second refractory layer obtained by casting refractory cement.

10. The preparation method of syngas prepared from biomass according to claim 1, characterized in that: A level gauge for measuring the material level of the material entering the furnace cavity of the inner furnace body is provided on the reaction furnace in the gasification reactor. During the process of continuously feeding the material into the gasification reaction chamber through the feeding auger, the set position of the material in the gasification reaction chamber is determined by the level gauge; a temperature sensor for measuring the temperature in the furnace cavity of the inner furnace body is provided on the reaction furnace.

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