Biomass circulating fluidized bed gasifier
By employing air distribution plates, baffles, and guide tubes in the biomass circulating fluidized bed gasifier, the staged fluidization and crushing of biomass are achieved, solving the problem of incomplete reaction caused by the uneven size of biomass particles, improving reaction efficiency, and reducing carbon loss.
Patent Information
- Application Number
- CN202511627461.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-07
- Publication Date
- 2026-01-20
- Estimated Expiration
- Not applicable · inactive patent
AI Technical Summary
During the biomass gas production process, the varying sizes of biomass particles lead to the deposition of large particles or the entrainment of small particles, resulting in incomplete reactions and waste of carbon resources.
The design employs air distribution plates and baffles within the boiler to process biomass in stages using airflows with different wind speeds and oxygen contents. Combined with the structure of guide pipes and baffles, this achieves graded fluidization and crushing of large and small biomass particles, thereby improving the fullness of the reaction.
It improves the completeness of biomass reaction, reduces carbon resource loss, and enhances reaction efficiency and gasification effect.
Smart Images
Figure CN121362601A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of gasification furnace, in particular to a biomass circulating fluidized bed gasification furnace. BACKGROUND
[0002] In the process of biomass gas production, due to the different particle sizes of the biomass put into the boiler, when the biomass reacts in the boiler, stratification phenomenon is prone to occur. That is, the large particles of biomass with large mass sink to the bottom of the boiler, and the small particles of biomass with small mass float on the top of the boiler. At this time, the gas flow in the boiler cannot adapt to the complex particle environment. When the gas flow in the boiler is small, although the small particles of biomass can produce good fluidization effect under the action of the gas flow, the large particles of biomass are prone to deposit at the bottom of the boiler, and it is difficult to achieve ideal fluidization state, and cannot fully react. In this case, a large amount of large particles of biomass which have not fully reacted will be directly discharged when the slag is discharged, causing waste of carbon resources. When the gas flow in the boiler is large, although the large particles of biomass can achieve ideal fluidization state, the small particles of biomass are prone to be carried out of the boiler by the gas flow. The residence time of the small particles of biomass in the boiler is greatly shortened, resulting in insufficient reaction and causing carbon loss. SUMMARY
[0003] The purpose of the present application is to improve the degree of reaction and reduce carbon loss.
[0004] In particular, the present application provides a biomass circulating fluidized bed gasification furnace, comprising: a boiler, a feeding port is arranged at the side; a wind distribution plate is arranged in the boiler and located below the feeding port; the wind distribution plate is conical and protrudes upward, and a plurality of air holes are arranged on the wind distribution plate at intervals; a plurality of partitions are arranged above the wind distribution plate at intervals and arranged along the periphery of the wind distribution plate; a first air inlet passage is arranged below the wind distribution plate and sends air upward through the plurality of air holes; a second air inlet passage is arranged below the wind distribution plate and sends air to the outer periphery of the plurality of partitions; wherein the wind speed of the first air inlet passage is smaller than that of the second air inlet passage, and the oxygen content of the first air inlet passage is smaller than that of the second air inlet passage.
[0005] Further, the biomass circulating fluidized bed gasification furnace further comprises: a plurality of guide pipes arranged at intervals on the outer periphery of the wind distribution plate and communicated with the second air inlet passage; the plurality of guide pipes send air upward at an inclination, so that the outer periphery of the partition forms a spiral air flow; wherein the rotation direction of the air flow outside the partition is variable; the plurality of partitions are in the shape of a vortex, and a wedge-shaped gap is formed between every two adjacent partitions; when the rotation direction of the air flow outside the partition is the same as that of the partition, part of the biomass outside the partition can enter the inside of the partition through the gap between the partitions.
[0006] Further, the guide pipe is swingably arranged on the second air inlet passage in the tangential direction of the wind distribution plate, for changing the rotation direction and the spiral angle of the air flow formed on the outer periphery of the partition.
[0007] Further, a plurality of rotatable connecting pipes are arranged in the second air inlet passage, and the plurality of connecting pipes correspond to the plurality of guide pipes one by one; a strip-shaped hole is arranged on the second air inlet passage corresponding to each connecting pipe, and the guide pipe passes through the strip-shaped hole to communicate with the corresponding connecting pipe; a spiral blade is arranged in the connecting pipe, and when the gas in the second air inlet passage flows through the spiral blade, the connecting pipe is pushed to rotate and drive the guide pipe to swing; a control valve is arranged at both ends of each connecting pipe in the second air inlet passage, for controlling the direction of the gas in the second air inlet passage flowing into the connecting pipe.
[0008] Further, the guide pipe is configured to intermittently change the guide direction, so that the rotation direction of the gas flow outside the baffle is intermittently changed.
[0009] Further, a baffle is arranged in the boiler, the baffle is annular, is sleeved on the outer periphery of the plurality of baffles, and is located above the plurality of guide pipes; wherein a plurality of screen holes are arranged on the baffle in a spaced manner.
[0010] Further, a first connecting rod is fixed on the outer side wall of each baffle; a limiting ring is arranged on the inner wall of the boiler, and the baffle is movably arranged above the limiting ring in the vertical direction; a plurality of second connecting rods are hingedly arranged on the inner wall of the baffle in a circumferential direction, and the plurality of second connecting rods correspond to the plurality of first connecting rods one by one; a plurality of third connecting rods are fixed on the inner wall of the boiler in a circumferential direction, and the plurality of third connecting rods correspond to the plurality of second connecting rods one by one, and the third connecting rod is located between the first connecting rod and the second connecting rod; a fourth connecting rod is hingedly connected to the end of the third connecting rod, and the two ends of the fourth connecting rod are hingedly connected to the first connecting rod and the second connecting rod respectively; when the baffle moves upward, the baffle is pushed to move towards the inside of the boiler by the fourth connecting rod, the second connecting rod and the first connecting rod.
[0011] Further, a plurality of positioning blocks are arranged on the inner wall of the boiler in a circumferential direction, and the plurality of positioning blocks correspond to the plurality of first connecting rods one by one; a through slot is arranged on the end face of the positioning block facing the first connecting rod, and a tension spring is connected to the groove bottom of the through slot; the first connecting rod extends into the through slot and is connected to the tension spring.
[0012] Further, a plurality of positioning plates are arranged on the periphery of the air distribution plate in a spaced manner, and a long strip-shaped hole is arranged on each positioning plate; the plurality of guide pipes pass through the plurality of long strip-shaped holes one by one and swing in the long strip-shaped holes; a hook is arranged on the bottom end of the baffle opposite to the guide pipe, the hook is sleeved on the outer periphery of the guide pipe, and the contact surface between the hook and the guide pipe is an inclined surface; when the baffle moves towards the inside of the boiler, the hook pushes the guide pipe to slide along the inclined surface, so that the inclination angle of the guide pipe is reduced.
[0013] Further, the biomass circulating fluidized bed gasification furnace further comprises: a feeding and crushing device arranged at the side of the boiler and connected with the feeding port, used for feeding the crushed biomass into the boiler; a circulating and separating device arranged at the side of the boiler, used for discharging the gas generated by the boiler and feeding the separated solid back into the boiler; and an oxygen mixing device used for feeding mixed gas into the first gas inlet passage and the second gas inlet passage respectively.
[0014] The present application has the following advantages: The biomass circulating fluidized bed gasification furnace of the present application divides the space above the air distribution plate into two parts by arranging a partition plate and a conical air distribution plate in the boiler. Then, the gas streams with different wind speeds and different oxygen contents are fed into the inner circle and the outer circle of the partition plate respectively, so that after the biomass falls into the boiler, the small-particle biomass floats up to reach the fluidized state under the low-speed gas stream, and the large-particle biomass slides along the inclined surface of the air distribution plate to the outer periphery of the partition plate. After the large-particle biomass slides to the outer periphery of the partition plate, it also floats up to reach the fluidized state under the high-speed gas stream outside the partition plate. The biomass is classified by size, and then the gas streams with different wind speeds and different oxygen contents are fed into the biomass of different sizes, so that the biomass of different sizes can all reach a good fluidized state, and the temperature environment around the biomass is more suitable for the size of the biomass, thereby improving the reaction completeness of the biomass and reducing the loss of carbon resources.
[0015] Further, the biomass circulating fluidized bed gasification furnace of the present application is provided with a guide pipe inclined upward to feed air, so that a spiral gas stream is formed around the outer periphery of the partition plate. The gas stream drives the large-particle biomass outside the partition plate to float up, and at the same time, drives the large-particle biomass to rotate spirally, so as to utilize the centrifugal force to make the large-particle biomass collide with the inner wall of the boiler, thereby crushing the large-particle biomass into small-particle biomass, and further improving the reaction efficiency. The partition plate is arranged in a vortex shape. When the rotation direction of the gas stream outside the partition plate is the same as the rotation direction of the partition plate, the small-particle biomass produced by the collision is guided by the partition plate to pass through the gap between the partition plates and enter the inner side of the partition plate, so as to reach the fluidized state under the low-speed gas stream on the inner side of the partition plate, and to improve the residence time of the small-particle biomass in the boiler, thereby improving the reaction completeness.
[0016] Further, the biomass circulating fluidized bed gasification furnace of the present application is provided with a guide pipe that can swing, so that the rotation direction and the spiral angle of the gas stream formed around the outer periphery of the partition plate can be adjusted, thereby adjusting the crushing efficiency of the large-particle biomass, and further improving the overall reaction effect. BRIEF DESCRIPTION OF DRAWINGS
[0017] Some specific embodiments of the present application will be described in detail hereinafter with reference to the accompanying drawings, which are presented by way of example and are not limiting. Like reference numerals in the drawings denote the same or similar components or parts. In the drawings: Figure 1is a structural schematic diagram of a biomass circulating fluidized bed gasifier according to an embodiment of the present application; Figure 2 is an exploded schematic diagram of a biomass circulating fluidized bed gasifier according to an embodiment of the present application; Figure 3 is an exploded schematic diagram of a boiler according to an embodiment of the present application; Figure 4 is Figure 3 an exploded schematic diagram of a partial structure of the boiler in Figure 5 is a structural schematic diagram of a baffle, a partition according to an embodiment of the present application; Figure 6 is a structural schematic diagram of a wind distribution plate, a first air inlet passage, a second air inlet passage according to an embodiment of the present application; Figure 7 is a structural schematic diagram of a second air inlet passage according to an embodiment of the present application; Figure 8 is a structural schematic diagram of a partition, a second air inlet passage according to an embodiment of the present application; Figure 9 is Figure 3 a top view schematic diagram of a partial structure of the boiler in Figure 10 is a schematic cross-sectional view taken along the section line A-A in Figure 9 Figure 11 is Figure 10 a schematic enlarged view of the region B in Figure 12 is Figure 10 a schematic enlarged view of the region C in Figure 13 is a schematic cross-sectional view taken along the section line D-D in Figure 10
[0018] wherein: 100. Boiler; 101. Feed inlet; 1001. Reaction cylinder; 1002. Classifying cylinder; 1003. Air supply cylinder; 110. Air distribution plate; 111. Air vent; 112. Fixing plate; 113. Positioning plate; 114. Long through hole; 120. Baffle plate; 121. First connecting rod; 122. Hook; 130. First air inlet passage; 140. Second air inlet passage; 141. Guide pipe; 142. Connecting pipe; 1421. Spiral blade ; 143, strip-shaped hole; 144, control valve; 150, baffle; 151, sieve hole; 152, second connecting rod; 160, limit ring; 170, third connecting rod; 171, fourth connecting rod; 180, positioning block; 181, through groove; 182, tension spring; 183, screw; 190, third air inlet passage; 200, feeding and crushing device; 300, circulating separation device; 400, oxygen mixing device; 500, steam blowing device. Detailed Implementation
[0019] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below through embodiments and in conjunction with the accompanying drawings. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
[0020] The terms "first," "second," "third," and "fourth" used herein are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first," "second," "third," or "fourth" may explicitly or implicitly include at least one of that feature, that is, include one or more of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified. When a feature "includes or contains" one or more of the features it encompasses, unless otherwise specifically stated, this indicates that other features are not excluded and may be further included.
[0021] Unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art should be able to understand the specific meaning of the above terms in this invention according to the specific circumstances.
[0022] The following reference Figures 1 to 13 This invention describes a biomass circulating fluidized bed gasifier.
[0023] The embodiment provides a biomass circulating fluidized bed gasification furnace. The biomass circulating fluidized bed gasification furnace can generally comprise a boiler 100, a wind distribution plate 110, a plurality of partitions 120, a first air inlet passage 130 and a second air inlet passage 140.
[0024] The boiler 100 is provided with a feeding port 101. The wind distribution plate 110 is arranged in the boiler 100 and below the feeding port 101. The wind distribution plate 110 is in the shape of a cone protruding upward, and a plurality of air holes 111 are arranged on the wind distribution plate 110 at intervals. The plurality of partitions 120 are arranged above the wind distribution plate 110 and are arranged at intervals along the periphery of the wind distribution plate 110. The first air inlet passage 130 is arranged below the wind distribution plate 110 and sends air upward through the plurality of air holes 111. The second air inlet passage 140 is arranged below the wind distribution plate 110 and sends air to the outer periphery of the plurality of partitions 120. The wind speed of the first air inlet passage 130 is less than that of the second air inlet passage 140, and the oxygen content of the first air inlet passage 130 is less than that of the second air inlet passage 140.
[0025] After the biomass is fed into the boiler 100 through the feeding port 101, small-particle biomass is floated in the boiler 100 to reach a fluidized state under the action of the low-speed airflow of the first air inlet passage 130. After the large-particle biomass falls, it slides along the inclined surface of the cone-shaped wind distribution plate 110 to the periphery. After the large-particle biomass slides to the outer periphery of the partition 120, it floats to reach a fluidized state under the action of the high-speed airflow of the second air inlet passage 140.
[0026] The large-particle biomass has a relatively small contact area with the airflow due to the large particle size, and the reaction rate is slow. The oxidation reaction of the large-particle biomass can be accelerated by introducing a gas with a higher oxygen content, which can provide sufficient heat to promote the pyrolysis and gasification reactions, so that the large-particle biomass can be more fully reacted. The small-particle biomass has a relatively large contact area with the airflow, and the reaction rate is fast. By introducing a gas with a lower oxygen content, the reaction can be avoided from being too violent, and local overheating and excessive combustion can be prevented.
[0027] The scheme of the embodiment classifies the biomass according to size, and then introduces airflows with different wind speeds to the biomass of different sizes, so that the biomass of different sizes can all reach a good fluidized state, thereby improving the full reaction degree of the biomass and reducing the loss of carbon resources. At the same time, airflows with different oxygen contents are introduced to the biomass of different sizes, so that the temperature environment around the biomass is adapted to the size of the biomass, thereby improving the overall reaction efficiency.
[0028] As Figure 10As shown, the lower part of the air distribution plate 110 is provided with a fixed plate 112, and a tapered cavity is formed between the fixed plate 112 and the air distribution plate 110. The first air inlet passage 130 is in communication with the cavity between the fixed plate 112 and the air distribution plate 110. The gas sent out by the first air inlet passage 130 is blown vertically upward through the air holes 111 on the air distribution plate 110, and the risk of gas flow leakage of the first air inlet passage 130 to the outer periphery of the partition plate 120 is reduced. The first air inlet passage 130 can include a plurality of first branch pipes uniformly distributed around the axis of the air distribution plate 110, so that the upwardly sent gas flow of the first air inlet passage 130 is more uniform and unobstructed.
[0029] The biomass circulating fluidized bed gasification furnace can also generally include a plurality of guide pipes 141. The plurality of guide pipes 141 are arranged at intervals on the outer periphery of the air distribution plate 110 and are in communication with the second air inlet passage 140. The plurality of guide pipes 141 tilt upward to send air, so that the outer periphery of the partition plate 120 forms a spiral gas flow. The direction of rotation of the gas flow outside the partition plate 120 can be changed. The plurality of partition plates 120 are in a vortex shape, and a wedge-shaped gap is formed between every two adjacent partition plates 120. When the direction of rotation of the gas flow outside the partition plate 120 is the same as the direction of rotation of the partition plate 120, part of the biomass outside the partition plate 120 enters the inner side of the partition plate 120 through the gap between the partition plates 120.
[0030] According to the scheme of the embodiment, the plurality of guide pipes 141 tilt upward to send air, so that the outer periphery of the partition plate 120 forms a spiral gas flow. While the gas flow drives the large-particle biomass outside the partition plate 120 to float upward, the large-particle biomass is driven to rotate in a spiral manner, so that the large-particle biomass collides with the inner wall of the boiler 100 by centrifugal force, the large-particle biomass is broken into small-particle biomass, and the reaction efficiency is improved.
[0031] As shown in FIG. 1, the plurality of partition plates 120 are arranged in a vortex shape, and the direction of rotation of the partition plates 120 is clockwise. The direction of rotation of the gas flow outside the partition plate 120 can be changed. Figure 9 As shown, the partition plate 120 is in a vortex shape, and the partition plate 120 is arranged in a clockwise direction from the side close to the barrel wall of the boiler 100 to the side close to the center of the boiler 100. The direction of rotation of the partition plate 120 is clockwise, and a wedge-shaped gap is formed between every two adjacent partition plates 120. When the direction of rotation of the gas flow outside the partition plate 120 is the same as the direction of rotation of the partition plate 120 (i.e., the direction of rotation of the gas flow outside the partition plate 120 is also clockwise), the small-particle biomass wrapped in the gas flow enters the inner side of the partition plate 120 under the guidance of the partition plate 120 through the gap between the partition plates 120. After the small-particle biomass enters the inner side of the partition plate 120, it reaches a fluidized state under the action of the low-speed gas flow inside the partition plate 120, the residence time of the small-particle biomass in the boiler 100 is prolonged, and the reaction completeness is improved.
[0032] As shown in FIG. 1, the plurality of partition plates 120 are arranged in a vortex shape, and the direction of rotation of the partition plates 120 is clockwise. The direction of rotation of the gas flow outside the partition plate 120 can be changed. Figure 9As shown, the baffle 120 is arc-shaped and is arranged to bend towards the inside of the boiler 100. When the rotation direction of the airflow outside the baffle 120 is the same as the rotation direction of the baffle 120 (i.e. the airflow outside the baffle 120 rotates clockwise in the middle), the small-particle biomass entrained in the airflow has less resistance when passing through the wedge-shaped gap between the baffles 120, making the screening of the small-particle biomass more smooth. Figure 9
[0033] In further embodiments, the guide pipe 141 can be swingably arranged on the second air inlet passage 140 along the tangent direction of the air distribution plate 110, for changing the rotation direction and the helical lift angle of the airflow formed outside the baffle 120.
[0034] When the rotation direction of the airflow outside the baffle 120 is the same as the rotation direction of the baffle 120, the large-particle biomass in the airflow collides with the inner wall of the boiler 100 and is broken. At the same time, the small-particle biomass in the airflow moves along the inner side wall of the baffle 120 and is screened to the inside of the baffle 120 through the gap between the baffles 120.
[0035] When the rotation direction of the airflow outside the baffle 120 is opposite to the rotation direction of the baffle 120, the biomass in the airflow cannot enter the inside of the baffle 120 through the gap between the baffles 120, and the biomass collides with the inner wall of the boiler 100 and the outer side wall of the baffle 120 and is broken.
[0036] The more the guide pipe 141 approaches the vertical state, the greater the helical lift angle of the airflow formed by the guide pipe 141. The greater the helical lift angle of the airflow outside the baffle 120, the smaller the centrifugal force of the biomass entrained in the airflow, and the weaker the breaking effect caused by collision. Conversely, the greater the inclination angle of the guide pipe 141, the smaller the helical lift angle of the airflow outside the baffle 120, the greater the centrifugal force of the biomass entrained in the airflow, and the stronger the breaking effect caused by collision.
[0037] In the present embodiment, the guide pipe 141 is swingable, so that the rotation direction and the helical lift angle of the airflow formed outside the baffle 120 are adjustable. By changing the rotation direction of the airflow, the biomass outside the baffle 120 is controlled to be broken alone or simultaneously broken and screened. By changing the helical lift angle of the airflow, the breaking efficiency of the biomass is controlled, thereby improving the overall reaction effect.
[0038] The helical lift angle of the helical airflow is controllable, the centrifugal force is used to control the breaking efficiency of the large particles, and the overall effect is improved. When the small-particle biomass accumulates and blocks the screen holes 151 of the baffle 150, the helical lift angle is increased, the centrifugal force is reduced, and the breaking efficiency is reduced, so that the small-particle biomass is discharged, and then the breaking efficiency is increased.
[0039] According to the quantity of small particle biomass generated by the crushing of large particle biomass, the crushing efficiency is adjusted, so that the small particles can enter the inner side of the baffle 120 in time, the overall reaction effect is improved, and the carbon loss is reduced.
[0040] A plurality of rotatable connecting pipes 142 are arranged in the second air inlet passage 140, and the plurality of connecting pipes 142 correspond to the plurality of guide pipes 141 one by one. Each connecting pipe 142 is provided with a strip-shaped hole 143 on the second air inlet passage 140, and the guide pipe 141 passes through the strip-shaped hole 143 and is in communication with the corresponding connecting pipe 142. The connecting pipe 142 is provided with a spiral blade 1421, and when the gas in the second air inlet passage 140 flows through the spiral blade 1421, the connecting pipe 142 is pushed to rotate and drives the guide pipe 141 to swing. The second air inlet passage 140 is provided with a control valve 144 at both ends of each connecting pipe 142, which is used to control the direction of the gas flow in the second air inlet passage 140 into the connecting pipe 142.
[0041] The scheme of the embodiment is that the rotatable connecting pipe 142 is arranged in the second air inlet passage 140, and the spiral blade 1421 is arranged in the connecting pipe 142, so that when the gas flow in the second air inlet passage 140 flows through the spiral blade 1421, the spiral blade 1421 can be pushed to rotate, thereby driving the connecting pipe 142 and the guide pipe 141 to rotate. The structure is simple, and the operation is stable.
[0042] The second air inlet passage 140 can supply air to both ends of the connecting pipe 142. By arranging the control valve 144 on both sides of the connecting pipe 142, the on-off state of the pipeline at both ends of the connecting pipe 142 is adjusted, thereby changing the flow path of the gas flow in the second air inlet passage 140, changing the deflection direction of the guide pipe 141, and further changing the spiral direction of the gas flow outside the baffle 120. The operation is simple, and the cost is low.
[0043] The control valve 144 preferably adopts a solenoid valve, which is not only fast in response and accurate in control, but also high in reliability and strong in adaptability.
[0044] As shown in Figures 6-7 In some embodiments, the second air inlet passage 140 can include a plurality of second branch pipes uniformly distributed around the axis of the cloth wind board 110, and each second branch pipe is provided with a corresponding guide pipe 141. In order to facilitate installation, each second branch pipe can be composed of a plurality of pipe sections, which are connected in sequence by screw connection.
[0045] As shown in Figures 6-7As shown, the strip-shaped holes 143 are arranged along the circumferential direction of the second branch pipe, and the length direction of the strip-shaped holes 143 is coplanar with the tangential direction of the air distribution plate 110. The guide pipe 141 swings in the strip-shaped hole 143, and the length of the strip-shaped hole 143 limits the maximum deflection angle of the guide pipe 141, i.e., limits the minimum helical angle of the air flow outside the baffle 120, thereby ensuring the fluidization effect.
[0046] The guide pipe 141 is configured to intermittently change the guide direction, so that the rotation direction of the air flow outside the baffle 120 is intermittently changed.
[0047] According to the scheme of the embodiment, the guide pipe 141 is arranged to intermittently change the guide direction, so that the rotation direction of the air flow outside the baffle 120 is intermittently changed, thereby intermittently screening the small particle biomass generated by collision into the baffle 120 in the process of collision and fragmentation of the biomass outside the baffle 120, and thereby improving the overall reaction efficiency.
[0048] In some preferred embodiments, a suitable control program can be preset according to test data, so that the guide direction of the guide pipe 141 is periodically changed.
[0049] The boiler 100 is provided with a baffle 150, which is annular, is arranged on the outer periphery of the plurality of baffles 120, and is located above the plurality of guide pipes 141. The baffle 150 is provided with a plurality of screen holes 151.
[0050] According to the scheme of the embodiment, the baffle 150 is arranged, and the screen holes 151 are arranged on the baffle 150, so that the small particle biomass generated by collision outside the baffle 120 is discharged upward through the screen holes 151, and the large particle biomass is blocked below the baffle 150. The large particle biomass is continuously fragmented under the action of the helical air flow in the fluidized state during the gasification reaction, so that the reaction of the biomass is more sufficient, thereby reducing the carbon loss.
[0051] The outer side wall of each baffle 120 is fixed with a first connecting rod 121. The inner wall of the boiler 100 is provided with a limiting ring 160, and the baffle 150 is movably arranged above the limiting ring 160 in the vertical direction. The inner wall of the baffle 150 is hingedly arranged with a plurality of second connecting rods 152 at intervals in the circumferential direction, and the plurality of second connecting rods 152 and the plurality of first connecting rods 121 correspond one by one. The inner wall of the boiler 100 is fixed with a plurality of third connecting rods 170 at intervals in the circumferential direction, and the plurality of third connecting rods 170 and the plurality of second connecting rods 152 correspond one by one, and the third connecting rod 170 is located between the first connecting rod 121 and the second connecting rod 152. The end of the third connecting rod 170 is hingedly connected with a fourth connecting rod 171, and the two ends of the fourth connecting rod 171 are hingedly connected with the first connecting rod 121 and the second connecting rod 152, respectively. When the baffle 150 moves upwards, the baffle 150 is pushed to move towards the inside of the boiler 100 by the fourth connecting rod 171, the second connecting rod 152 and the first connecting rod 121.
[0052] When the small-particle biomass generated by the collision of the outer side wall of the baffle 120 is more, and the small-particle biomass cannot be discharged in time, causing the screen holes 151 of the baffle 150 to be blocked, under the action of the airflow, the baffle 150 moves upwards. The upward movement of the baffle 150 drives the second connecting rod 152 to rotate, and the second connecting rod 152 drives the fourth connecting rod 171 to rotate. The fourth connecting rod 171 rotates around the hinge point of the fourth connecting rod 171 and the third connecting rod 170, so that the first connecting rod 121 moves towards the inside of the boiler 100 and downwards at the same time, thereby driving the baffle 120 to move towards the inside of the boiler 100 and downwards. The movement of the baffle 120 towards the inside of the boiler 100 causes the space around the outer side wall of the baffle 120 to increase, thereby increasing the activity space of the small-particle biomass accumulated near the outer side wall of the baffle 120. The small-particle biomass becomes loose between each other, so that it is easier to be screened into the inside of the baffle 120. The downward movement of the baffle 120 reduces the gap between the baffle 120 and the air distribution plate 110, thereby reducing the sliding speed of the large-particle biomass towards the outside of the baffle 120, and further reducing the speed of the small-particle biomass generated by the collision of the outer side wall of the baffle 120, and reducing the accumulation speed of the small-particle biomass.
[0053] When the small-particle biomass accumulated on the outer side of the baffle 120 is screened into the inside of the baffle 120 through the gap between the baffles 120, and when the screen holes 151 on the baffle 150 are restored to be unobstructed, the baffle 150 moves downwards under the action of gravity until the baffle 150 abuts against the limiting ring 160. When the baffle 150 moves downwards, the baffle 120 is driven to move outwards in sequence through the second connecting rod 152, the fourth connecting rod 171 and the first connecting rod 121, so as to reset the baffle 120.
[0054] The scheme of the embodiment is that after the small-particle biomass outside the partition plate 120 is accumulated to block the sieve hole 151, the airflow outside the partition plate 120 is used to push the baffle 150 to move upwards, so that the position of the partition plate 120 is changed through the first connecting rod 121, the second connecting rod 152 and the fourth connecting rod 171, the discharging rate of the small-particle biomass is accelerated, and the output speed of the small-particle biomass is reduced, so that the accumulation of the small-particle biomass outside the partition plate 120 is solved. The small-particle biomass is timely screened to the inside of the partition plate 120, so that the small-particle biomass is prevented from being excessively combusted, the overall gasification efficiency is improved, and the risk of local overheating outside the partition plate 120 is reduced.
[0055] A plurality of positioning blocks 180 are arranged on the inner wall of the boiler 100 in a circumferential direction, and the plurality of positioning blocks 180 and the plurality of first connecting rods 121 are in one-to-one correspondence. The end face of the positioning block 180 facing the first connecting rod 121 is provided with a through groove 181, and the groove bottom of the through groove 181 is connected with a tension spring 182. The first connecting rod 121 extends into the through groove 181 and is connected with the tension spring 182.
[0056] The scheme of the embodiment is that the positioning block 180 is arranged on the inner wall of the boiler 100, and the tension spring 182 connected with the first connecting rod 121 is arranged in the through groove 181 of the positioning block 180, so that the first connecting rod 121 is driven by the pulling force of the tension spring 182 to drive the partition plate 120 to reset, and the resetting of the partition plate 120 is more smooth.
[0057] As shown in Figure 5 , the positioning block 180 can be provided with a screw 183, and the positioning block 180 is fixed on the inner wall of the boiler 100 through the screw 183.
[0058] A plurality of positioning plates 113 are arranged on the periphery of the air distribution plate 110 in a spaced manner, and each positioning plate 113 is provided with a long strip through hole 114. A plurality of guide pipes 141 pass through the plurality of long strip through holes 114 in a one-to-one correspondence and swing in the long strip through holes 114. The bottom end of the partition plate 120 opposite to the guide pipe 141 is provided with a hook claw 122, the hook claw 122 is sleeved on the outer periphery of the guide pipe 141, and the contact surface of the hook claw 122 and the guide pipe 141 is an inclined surface. When the partition plate 120 moves towards the inside of the boiler 100, the hook claw 122 pushes the guide pipe 141 to slide along the inclined surface, so that the inclination angle of the guide pipe 141 is reduced.
[0059] The scheme of the embodiment is that the hook claw 122 is arranged, the movement of the partition plate 120 drives the movement of the hook claw 122, the guide pipe 141 moves along the inclined surface of the hook claw 122, so that the inclination angle of the guide pipe 141 is reduced, the helix angle of the airflow outside the partition plate 120 is increased, and then the centrifugal force received by the biomass outside the partition plate 120 is reduced, so that the breaking efficiency is reduced.
[0060] As shown in Figure 5 ,8 As shown, the hook 122 is positioned on the side opposite to the rotation direction of the partition 120. When the rotation direction of the airflow outside the partition 120 is opposite to that of the partition 120 (i.e., when the biomass outside the partition 120 only collides and is not screened), the baffle 150 moves upward after blocking, causing the partition 120 to move inward, thereby causing the hook 122 to move. This reduces the tilt angle of the guide tube 141 (i.e., tends to be vertical), thereby reducing the crushing efficiency of the biomass outside the partition 120 and preventing the blockage from worsening.
[0061] When the swirling direction of the airflow outside the baffle 120 is the same as the swirling direction of the baffle 120 (i.e., when the biomass outside the baffle 120 collides and is screened simultaneously), the guide tube 141 tilts away from the side opposite to the hook 122. Therefore, the movement of the hook 122 will not cause a change in the tilt angle of the guide tube 141, and the spiral angle of the airflow outside the baffle 120 is kept to a minimum, thereby ensuring the screening efficiency of the airflow.
[0062] The elongated hole on the positioning plate 113 provides room for the deflection of the guide tube 141.
[0063] A biomass circulating fluidized bed gasifier may also generally include a third air inlet passage 190. The third air inlet passage 190 is located below the second air inlet passage 140 and supplies air vertically upward. The air velocity and oxygen content of the third air inlet passage 190 are the same as those of the second air inlet passage 140.
[0064] like Figure 6 As shown, a gap is formed between any two adjacent positioning plates 113. The air from the third air intake passage 190 is blown upward through the gap between the adjacent positioning plates 113, causing the biomass that has slid down to the gap between the adjacent positioning plates 113 to float upward and reach a fluidized state. After the biomass in the boiler 100 completes the reaction, the first air intake passage 130, the second air intake passage 140, and the third air intake passage 190 stop supplying air. The slag falls to the bottom of the boiler 100 through the gap between the positioning plates 113, and is then discharged through the discharge port at the bottom of the boiler 100 (not shown in the figure).
[0065] A biomass circulating fluidized bed gasifier may also include: a feeding and crushing device 200, a circulating separation device 300, and an oxygen mixing device 400.
[0066] A feeding and crushing device 200 is located on the side of the boiler 100 and connected to the feed inlet 101. It is used to crush biomass and feed it into the boiler 100. A circulating separator 300 is located on the side of the boiler 100 and is used to discharge the gas produced by the boiler 100 and return the separated solids to the boiler 100. An oxygen mixing device 400 is used to supply mixed gas to the first air inlet passage 130 and the second air inlet passage 140, respectively.
[0067] The oxygen mixing device 400 can be connected to a steam supply device 500. The steam supply device 500 is used to supply steam to the oxygen mixing device 400. After mixing oxygen, steam, and carbon dioxide, the oxygen mixing device 400 supplies mixed gases with different oxygen contents to the first air inlet passage 130 and the second air inlet passage 140, respectively. The boiler 100 is also equipped with an ignition device (not shown in the figure) to ignite the biomass fed into the boiler 100 and start the gasification process.
[0068] Biomass is fed into the feeding and crushing device 200, and then enters the boiler 100 through the feed inlet 101. A gasification reaction occurs inside the boiler 100, and the generated combustible gas, carrying some solid impurities, enters the circulating separation device 300 from the top of the boiler 100. The circulating separation device 300 discharges the combustible gas and then returns the separated solids to the boiler 100 through the circulation port at the bottom of the boiler 100 for further reaction.
[0069] like Figures 2-3 As shown, for ease of installation, the boiler 100 may include a reaction cylinder 1001, a classifying cylinder 1002, and an air supply cylinder 1003 connected sequentially from top to bottom. The feed inlet 101 and the circulation inlet are located on the side wall of the reaction cylinder 1001. The air distribution plate 110 and the baffle plate 120 are located inside the classifying cylinder 1002. The first air inlet passage 130, the second air inlet passage 140, and the third air inlet passage 190 are located inside the air supply cylinder.
[0070] The specific working process of the biomass circulating fluidized bed gasifier provided by the present invention will be described in conjunction with the above embodiments: First, the first air intake passage 130, the second air intake passage 140, and the third air intake passage 190 are activated to supply air. Then, the feeding and crushing device 200 is activated, injecting the biomass to be reacted into the boiler 100 through the feed inlet 101. Finally, the ignition device is activated.
[0071] Biomass is fed into boiler 100 and settles above air distribution plate 110. Small biomass particles rise to a fluidized state under the influence of airflow from the first air intake passage 130, and then undergo gasification. Larger biomass particles settle on air distribution plate 110 and slide around its conical slope. After settling around air distribution plate 110, the large biomass particles rise to a fluidized state under the influence of airflow from the second air intake passage 140 and the third air intake passage 190, and then spiral around the outer periphery of baffle plate 120.
[0072] In the process of rotating the large particle biomass, the large particle biomass collides with the cylinder wall of the boiler 100 under the centrifugal force and is broken into small particle biomass. The small particle biomass produced by the collision is partially lifted by the gas flow and discharged through the screen hole 151 on the baffle 150. By controlling the valve 144 to adjust the flow direction of the gas flow in the second air inlet passage 140, the rotation direction of the gas flow outside the baffle 120 is changed. When the rotation direction of the gas flow outside the baffle 120 and the rotation direction of the baffle 120 are in the same direction, the small particle biomass produced by the collision is partially screened to the inside of the baffle 120 through the gap between the baffles 120.
[0073] The combustible gas produced in the boiler 100 entrains part of the solid and flows into the circulating separation device 300 from the top of the boiler 100. The circulating separation device 300 discharges the combustible gas and sends the separated solid back into the boiler 100 through the circulating port for re-reaction.
[0074] After the biomass in the boiler 100 completes the reaction, the feeding and crushing device 200, the circulating separation device 300, and the oxygen mixing device 400 stop working. The first air inlet passage 130, the second air inlet passage 140, and the third air inlet passage 190 stop air supply, and the residue in the boiler 100 falls through the gap between the positioning plates 113 to the bottom of the boiler 100, and then is discharged through the discharge port at the bottom of the boiler 100.
[0075] The technical features of the above embodiments can be combined in any way. In order to make the description simple, not all possible combinations of the technical features in the above embodiments are described, but as long as the combinations of the technical features do not exist contradictory, they should be considered as the scope of the present application.
[0076] The above embodiments only express several embodiments of the present application, and the description is more specific and detailed, but it should not be understood as limiting the scope of the present application. It should be noted that for those skilled in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which are within the scope of the present application. Therefore, the protection scope of the present application should be subject to the appended claims.
Claims
1. A biomass circulating fluidized bed gasifier, characterized by, The utility model relates to a biomass gasification device, comprising: a boiler with a feed inlet on one side; a distribution plate arranged in the boiler below the feed inlet; the distribution plate is conical and upwardly convex, and a plurality of air holes are arranged on the distribution plate at intervals; a plurality of partitions are arranged above the distribution plate at intervals and are arranged along the periphery of the distribution plate at intervals; a first air inlet channel is arranged below the distribution plate and sends air upward through the plurality of air holes; a second air inlet channel is arranged below the distribution plate and sends air to the outer periphery of the plurality of partitions; wherein the air speed of the first air inlet channel is less than that of the second air inlet channel, and the oxygen content of the first air inlet channel is less than that of the second air inlet channel.
2. The biomass circulating fluidized bed gasifier according to claim 1, wherein, Further comprising: a plurality of guide pipes are arranged at intervals on the outer periphery of the distribution plate and communicate with the second air inlet channel; the plurality of guide pipes send air upward at an angle, forming a spiral airflow around the outer periphery of the partitions; wherein the direction of rotation of the airflow outside the partitions can be changed; the plurality of partitions are in the shape of a vortex, and a wedge-shaped gap is formed between every two adjacent partitions; when the direction of rotation of the airflow outside the partitions is the same as that of the partitions, part of the biomass outside the partitions can enter the inside of the partitions through the gap between the partitions.
3. The biomass circulating fluidized bed gasifier according to claim 2, wherein, the guide pipes can be arranged on the second air inlet channel to swing along the tangent direction of the distribution plate, for changing the direction of rotation and the helical angle of the airflow formed around the outer periphery of the partitions.
4. The biomass circulating fluidized bed gasifier according to claim 3, wherein, a plurality of rotatable connecting pipes are arranged in the second air inlet channel, and the plurality of connecting pipes correspond one-to-one to the plurality of guide pipes; a strip-shaped hole is arranged on the second air inlet channel opposite each connecting pipe, and the guide pipe passes through the strip-shaped hole to communicate with the corresponding connecting pipe; a spiral blade is arranged in the connecting pipe, and when the gas in the second air inlet channel flows through the spiral blade, the connecting pipe is driven to rotate and the guide pipe is driven to swing; a control valve is arranged at both ends of each connecting pipe in the second air inlet channel, for controlling the direction of the gas flow in the second air inlet channel into the connecting pipe.
5. The biomass circulating fluidized bed gasifier according to claim 4, wherein, the guide pipes are configured to change the guide direction intermittently, so that the direction of rotation of the airflow outside the partitions is changed intermittently.
6. The biomass circulating fluidized bed gasifier according to claim 4, wherein a baffle is arranged in the boiler, the baffle is annular, is sleeved on the outer periphery of the plurality of partitions, and is located above the plurality of guide pipes; wherein a plurality of screen holes are arranged at intervals on the baffle.
7. The biomass circulating fluidized bed gasifier according to claim 6, wherein, a first connecting rod is fixed to the outer side wall of each partition; a limiting ring is arranged on the inner wall of the boiler, and the baffle is movably arranged above the limiting ring in the vertical direction; a plurality of second connecting rods are hingedly arranged at intervals on the inner wall of the baffle in the circumferential direction, and the plurality of second connecting rods correspond one-to-one to the plurality of first connecting rods; a plurality of third connecting rods are fixed at intervals on the inner wall of the boiler in the circumferential direction, the plurality of third connecting rods correspond one-to-one to the plurality of second connecting rods, and the third connecting rods are located between the first connecting rods and the second connecting rods; a fourth connecting rod is hingedly connected to the end of the third connecting rod, and the two ends of the fourth connecting rod are hingedly connected to the first connecting rod and the second connecting rod respectively. When the baffle moves upward, the fourth connecting rod, the second connecting rod and the first connecting rod push the baffle to move toward the inside of the boiler.
8. The biomass circulating fluidized bed gasifier according to claim 7, wherein, The inner wall of the boiler is provided with a plurality of positioning blocks which are spaced apart in the circumferential direction, and the positioning blocks and the first connecting rods are in one-to-one correspondence; the end face of the first connecting rod is provided with a through slot, and the bottom of the through slot is connected with a tension spring; the first connecting rod extends into the through slot and is connected with the tension spring.
9. The biomass circulating fluidized bed gasifier according to claim 7, wherein, The periphery of the air distribution plate is provided with a plurality of positioning plates which are spaced apart, and each of the positioning plates is provided with a long strip-shaped through hole; a plurality of guide pipes pass through the long strip-shaped through holes in one-to-one correspondence and swing in the long strip-shaped through holes; The bottom end of the baffle opposite to the guide pipe is provided with a hook, the hook is sleeved on the outer periphery of the guide pipe, and the contact surface between the hook and the guide pipe is an inclined surface; when the baffle moves toward the inside of the boiler, the hook pushes the guide pipe to slide along the inclined surface, so that the inclination angle of the guide pipe is reduced.
10. The biomass circulating fluidized bed gasifier according to claim 1, wherein, Further comprising: a feeding and crushing device arranged at the side of the boiler and connected with the feeding port, for feeding the crushed biomass into the boiler; a circulating and separating device arranged at the side of the boiler, for discharging the gas produced by the boiler and feeding the separated solid back into the boiler; an oxygen mixing device for feeding mixed gas into the first gas inlet passage and the second gas inlet passage respectively.