Biomass gasification furnace, liquid fuel production equipment, and operational method for biomass gasification furnace

Abstract

To provide a biomass gasification furnace capable of suppressing clinker fastening to an inner wall of a gasification furnace body.SOLUTION: A biomass gasification furnace comprises: a gasification furnace body 2 formed as a cylindrical body having a central axis CL in a vertical direction to gasify a biomass feedstock inside; a screw feeder 3 charging the biomass feedstock into the gasification furnace body 2; and a gasification agent charging pipe 5 provided below the screw feeder 3 and introducing a gasifying agent into the gasification furnace body 2 to form a swirling flow around the central axis CL.SELECTED DRAWING: Figure 2A

Description

[Technical field]

[0001] The present disclosure relates to a biomass gasifier, a liquid fuel production facility, and a method for operating a biomass gasifier. [Background technology]

[0002] Conventionally, as disclosed in Patent Document 1, a gasification facility is known in which pulverized coal fuel, which is made by crushing and classifying coal in a mill, is supplied into the gasification furnace, and the pulverized coal fuel is partially combusted and gasified to produce combustible gas. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2016-41784 A Summary of the Invention [Problem to be solved by the invention]

[0004] In recent years, the use of biomass raw materials has been attracting attention as a means of combating global warming. In a biomass gasifier, oxygen and steam are fed into the gasifier from the bottom as gasifying agents, and the biomass raw materials are partially combusted with oxygen and heated to approximately 1200°C, and the heat generated during this process covers the heat required for the gasification reaction of the biomass raw materials. The gasification gas produced by the gasification reaction produces hydrogen through an equilibrium reaction of steam and CO shift reaction, and gasification gas consisting mainly of hydrogen and CO is produced at the outlet of the gasifier.

[0005] If the softening point of the ash of the biomass raw material fed into the gasification furnace is lower than the maximum temperature inside the gasification furnace, the ash will melt inside the furnace and adhere to the inner walls of the furnace, turning into clinker. If the amount of clinker increases, there is a risk of the gasification furnace becoming clogged.

[0006] Incidentally, coal-based gasifiers such as those in Patent Document 1 generally use a wet furnace in which ash is melted inside the gasifier and discharged from the discharge section at the bottom of the gasifier along the furnace wall. However, biomass gasifiers using biomass raw materials have less ash than coal, so a dry furnace is used in which the ash is not melted inside the gasifier, but is separated from the gasification gas in a solid state in a dust collector arranged downstream of the gasifier. Therefore, the same technical concept as that of a coal gasifier, which is a wet furnace, cannot be directly used for ash treatment in a biomass gasifier, which is a dry furnace.

[0007] The present disclosure has been made in consideration of the above circumstances, and aims to provide a biomass gasification furnace, a liquid fuel production facility, and an operating method for a biomass gasification furnace that can suppress clinker adhering to the inner wall of the gasification furnace body. [Means for solving the problem]

[0008] The biomass gasification furnace of the present disclosure is a cylinder having a central axis in the vertical direction, and includes a gasification furnace main body that gasifies biomass raw material inside, a biomass raw material input section that inputs the biomass raw material into the inside of the gasification furnace main body, and a gasification agent input section that is located below the biomass raw material input section and inputs a gasification agent into the inside of the gasification furnace main body so that a swirling flow is formed around the central axis.

[0009] A liquid fuel production facility of the present disclosure includes the biomass gasification furnace described above, and a liquid fuel synthesis facility that synthesizes liquid fuel from at least a portion of the synthesis gas produced in the gasification furnace.

[0010] The operating method of a biomass gasification furnace disclosed herein is a method for operating a biomass gasification furnace which includes a gasification furnace body which is a cylinder having a central axis in the vertical direction and which gasifies biomass raw material inside, a biomass raw material input section which inputs the biomass raw material into the inside of the gasification furnace body, and a gasification agent input section which is located below the biomass raw material input section and inputs a gasification agent into the inside of the gasification furnace body, wherein a swirling flow is formed around the central axis by the gasification agent input section. Effect of the Invention

[0011] It is possible to suppress the adhesion of clinker to the inner wall of the gasification furnace body. [Brief description of the drawings]

[0012] [Figure 1] 1 is a schematic configuration diagram showing a liquid fuel production facility according to an embodiment of the present disclosure. [Figure 2A] FIG. 2 is a front view showing the lower part of the gasification furnace body. [Figure 2B] FIG. 2B is a cross-sectional view taken at a height position of the gasifying agent input pipe of FIG. 2A. [Diagram 3] FIG. 4 is a cross-sectional view showing the input direction of the gasifying agent input portion. [Figure 4A] FIG. 11 is a schematic diagram showing the temperature distribution in a reference example. [Figure 4B] FIG. 2B is a schematic diagram showing the temperature distribution of the embodiment of FIG. 2A. [Figure 5A] FIG. 4 is a schematic diagram showing a gas flow in a reference example. [Figure 5B] FIG. 2B is a schematic diagram showing gas flows for the embodiment of FIG. 2A. [Figure 6] 1 is a graph showing a swirl ratio relative to the maximum particle diameter of fine particles for each inclination angle. [Figure 7A] FIG. 11 is a schematic diagram showing the effect of a reference example. [Figure 7B] FIG. 2B is a schematic diagram showing the effect of the embodiment of FIG. 2A. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present disclosure will now be described with reference to the drawings. Fig. 1 shows a liquid fuel production facility 10 according to an embodiment of the present disclosure. In the following explanation, "upper" refers to the vertically upper direction, and "upper" in terms such as upper part and upper surface refers to the vertically upper part. Similarly, "lower" refers to the vertically lower part, and the vertical direction is not precise and may include errors.

[0014] The liquid fuel production facility 10 according to this embodiment includes a gasification furnace 1 that uses oxygen and water vapor as gasifying agents. In the gasification furnace 1, a combustible gas (product gas) is produced from a biomass raw material.

[0015] In the liquid fuel production facility 10, the synthesis gas generated in the gasification furnace 1 is refined in a gas refining facility 16, and then supplied as a raw material for liquid fuel synthesis to a liquid fuel synthesis facility 17. The raw material supplied to the gasification furnace 1 may be, for example, wood-based biomass raw materials such as thinned wood, waste wood, driftwood, bark, paper sludge, agricultural residues, etc.

[0016] The liquid fuel production facility 10 includes a biomass raw material supply facility 11, a gasification furnace 1, an ash recovery facility 15, a gas refining facility 16, and a liquid fuel synthesis facility 17.

[0017] The biomass raw material supplying facility 11 is supplied with unpulverized biomass raw material and pulverizes the raw material in a mill (not shown) or the like to produce raw material pulverized into fine particles. The granular raw material produced by the biomass raw material supplying facility 11 is supplied to the gasification furnace 1 by a screw feeder 3 (biomass raw material input section).

[0018] The gasification furnace 1 includes a cylindrical gasification furnace body 2 having a central axis in the vertical direction. Granular raw material produced in a biomass raw material supply facility 11 is supplied into the gasification furnace body 2.

[0019] The air separation equipment 42 separates and generates oxygen from atmospheric air, and is connected to an oxygen supply line 47 that supplies oxygen toward the gasification furnace main body 2. In addition, a water vapor supply line 46 through which water vapor flows is connected to the oxygen supply line 47. The oxygen separated by the air separation equipment 42 flows through the oxygen supply line 47 and is used as a gasification agent in the gasification furnace 1. In addition, water vapor is supplied to the gasification furnace main body 2 from the water vapor supply line 46 as a gasification agent.

[0020] In the gasifier 1, particulate raw material supplied to the inside of the gasifier body 2 is partially combusted with oxygen and undergoes an aqueous shift reaction with water vapor to generate product gas containing hydrogen and carbon monoxide.

[0021] A first produced gas line 49 that supplies produced gas toward the ash recovery facility 15 is connected to the gasification furnace 1, and the produced gas containing ash can be discharged. In this case, a produced gas cooler (not shown) may be provided in the first produced gas line 49 to cool the produced gas to a predetermined temperature before supplying it to the ash recovery facility 15.

[0022] The ash recovery facility 15 includes a dust collector 51. In this case, the dust collector 51 is configured with one or a plurality of cyclones or porous filters, and is capable of separating ash contained in the generated gas generated in the gasifier 1. The generated gas from which the ash has been separated is sent to the gas purification facility 16 through a second generated gas line 53. The ash separated from the generated gas is sent to, for example, a hopper (not shown) or the like and temporarily stored therein.

[0023] The gas purification equipment 16 purifies the generated gas from which the ash has been separated by the ash recovery equipment 15 by removing impurities such as sulfur compounds and nitrogen compounds. The gas purification equipment 16 then purifies the generated gas and supplies it to the liquid fuel synthesis equipment 17.

[0024] The liquid fuel synthesis facility 17 produces liquid fuel such as methanol or ammonia using the product gas refined in the gas refinement facility 16 as a raw material.

[0025] Next, the operation of the liquid fuel production facility 10 of this embodiment will be described. In the liquid fuel production facility 10, when a biomass raw material is supplied to the biomass raw material supply facility 11, the biomass raw material is pulverized into particles in a mill in the biomass raw material supply facility 11. The particulate raw material produced in the biomass raw material supply facility 11 flows through a raw material supply line 12 and is supplied to the gasification furnace 1 via the screw feeder 3.

[0026] In the gasifier 1, the supplied particulate material is partially combusted with oxygen and undergoes an aqueous shift reaction with water steam to generate generated gas. The generated gas is then discharged from the gasifier 1 through a first generated gas line 49 and sent to the ash recovery facility 15.

[0027] In the ash recovery facility 15, the generated gas is first supplied to a dust collector 51, whereby fine ash contained in the generated gas is separated. Then, the generated gas from which the ash has been separated is sent to the gas purification facility 16 through a second generated gas line 53. On the other hand, the fine ash separated from the generated gas is sent to, for example, a hopper (not shown) or the like and temporarily stored therein, and then discharged outside the system.

[0028] The generated gas from which the ash has been separated by the ash recovery equipment 15 is purified in a gas purification equipment 16 to remove impurities such as sulfur compounds and nitrogen compounds, and is then sent to a liquid fuel synthesis equipment 17. In the liquid fuel synthesis equipment 17, liquid fuels such as methanol and ammonia are produced using the purified gas as a raw material.

[0029] Next, the supply of the biomass raw material and the gasifying agent to the gasifier 1 will be specifically described with reference to Figures 2A and 2B. Figure 2A shows the lower part of the gasifier body 2 of the gasifier 1. The gasifier 1 is a dry furnace in which ash generated from the biomass raw material is not melted in the gasifier body 2, but is separated in a solid state from the gasification gas by a dust collector 51 of an ash recovery facility 15 arranged downstream of the gasifier 1.

[0030] As shown in Fig. 2A, the gasifier body 2 has a cylindrical shape with a central axis CL extending in the vertical direction. The gasifier body 2 includes a main body portion 2a where partial combustion and gasification of biomass raw materials are mainly performed, a first tapered portion 2b connected to the lower end of the main body portion 2a and gradually reduced in diameter toward the bottom, a first cylindrical portion 2c connected to the lower end of the first tapered portion 2b and having a constant diameter, a second tapered portion 2d connected to the lower end of the first cylindrical portion 2c and gradually reduced in diameter toward the bottom, and a second cylindrical portion 2e connected to the lower end of the second tapered portion 2d and having a constant diameter. Therefore, the flow passage area of ​​the gas flowing in the gasifier body 2 increases in the order of the second cylindrical portion 2e, the first cylindrical portion 2c, and the main body portion 2a.

[0031] The raw material supply line 12 is connected to a screw feeder (biomass raw material input section) 3. The screw feeder 3 is driven by an electric motor 3a and rotates at a rotation speed commanded by a control section (not shown). This allows a predetermined amount of raw material (pulverized biomass raw material) to be supplied into the gasification furnace body 2. A cooling jacket 3b is provided on the outer periphery of the screw feeder 3 to prevent overheating of the raw material before supply.

[0032] The screw feeder 3 is connected to the first cylindrical portion 2c and feeds the raw material in a substantially horizontal direction. The number of screw feeders 3 may be one as shown in the figure, or multiple screw feeders 3 may be used. Note that, instead of the screw feeder 3, other feeding methods such as air current conveyance may be used as a method of feeding the raw material.

[0033] A gasifying agent introduction pipe (gasifying agent introduction section) 5 is provided below the screw feeder 3. The gasifying agent introduction pipe 5 is provided in the second cylindrical section 2e. It is preferable that a plurality of gasifying agent introduction pipes 5 are provided, and in this embodiment, four gasifying agent introduction pipes 5 are provided at equal angular intervals in the circumferential direction of the second cylindrical section 2e as shown in FIG. 2B. The gasifying agent introduction pipes 5 are provided at the same height position as shown in FIG. 2A. Oxygen and water vapor led from the air separation equipment 42 (see FIG. 1) are supplied from the gasifying agent introduction pipe 5 to the inside of the gasification furnace main body 2.

[0034] 2B, the gasifying agent introduction pipes 5 introduce the gasifying agent (oxygen and steam) in a direction inclined with respect to the central axis CL in a horizontal plane. The inclination angle of each of the four gasifying agent introduction pipes 5 is the same. This forms a swirling flow around the central axis CL.

[0035] 3 shows the inclination angle α of the gasifying agent introduction pipe 5. As shown in the figure, the inclination angle α is an angle with respect to a reference line BS that connects the introduction center position 5a of the gasifying agent introduction pipe 5 and the central axis line CL. Here, the introduction center position 5a of the gasifying agent introduction pipe 5 means the center position in the cross section of the piping that constitutes the gasifying agent introduction pipe 5 and the position that intersects with the second cylindrical portion 2e. The inclination angle α is set to be 5° or more and 50° or less. The gasifying agent fed at the inclination angle α is injected in the direction indicated by the arrow A1 at a flow velocity Uφ, forming a swirling flow with an imaginary circle radius r. In addition, in Fig. 3, the symbol Rt indicates the radius of the second cylindrical portion 2e (the distance from the central axis CL to the furnace wall (inner wall)).

[0036] Next, the swirl number Sw of the swirling flow formed by the gasifying agent injected from the gasifying agent injection pipe 5 will be considered. The swirl number Sw, which is a dimensionless number related to the strength of the turning force, is expressed by the following equation (1). Sw = Gφ / (Gt × Rt) (1) Here, Gφ indicates the angular momentum flow rate, Gt indicates the momentum flow rate in the direction of the central axis line CL, and Rt indicates the radius of the gasifier at the input location.

[0037] The gasification state in the gasifier body 2 when the swirl number Sw is set to 0.2 is calculated using CFD (Computational Fluid Dynamics) and is shown in Figures 4A and 4B. In the CFD, the calculation takes into account both the flow velocity and the temperature.

[0038] Fig. 4A shows a comparative example, and Fig. 4B shows this embodiment. In Fig. 4A and Fig. 4B, (a) shows the temperature distribution in the front view and side view of the gasifier body 2, and (b) shows the temperature distribution in the cross section at the height position AA shown in (a). The height position AA corresponds to the height position at which the raw material particles are fed by the screw feeder 3.

[0039] In the comparative example (FIG. 4A), the inclination angle α of the gasifying agent injection pipe 5 is set to 0°. Therefore, in the comparative example, no swirling flow is formed. In the temperature distribution inside the gasifier in the comparative example, high temperature areas (black areas) are generated near the furnace wall (inner wall) in the top view of the AA cross section of the gasifier body 2 (FIG. 4A (b)), and when using biomass fuel with an ash softening point of 1200°C or less, ash melts near the furnace wall and adheres to the wall surface.

[0040] In contrast, in the gasification furnace 1 of this embodiment shown in Fig. 4B, a high temperature part is generated in the center in the top view of the AA cross section of the gasification furnace body 2 (Fig. 4B (b)), but it can be seen that there is no high temperature part near the furnace wall (inner wall). Therefore, even with biomass fuel with an ash softening point of 1200°C or less, the temperature near the furnace wall is low, so the ash is less likely to melt near the furnace wall, and adhesion of ash to the furnace wall can be prevented.

[0041] 5A and 5B show how the flow inside the gasifier body 2 changes depending on the strength of the swirling flow formed by the gasifier introduced from the gasifier introduction pipe 5. In Fig. 5A and 5B, the left diagram shows the gas flow when the gasifier body 2 is viewed from the front, and the right diagram shows the vertical flow velocity of the gas flow (vertical upward velocity is taken as a positive value) at the BB cross section and the CC cross section. The BB cross section and the CC cross section correspond to the height position where the raw material particles are introduced by the screw feeder 3.

[0042] FIG. 5A is a reference example, showing a case where a relatively strong swirl is applied with a swirl number Sw greater than 0.25, and a downward backflow region is generated in the central region of the gasification furnace body 2.

[0043] FIG. 5B shows the present embodiment, in which the swirl number Sw is between 0.1 and 0.25, both inclusive, and is a relatively weak swirl, and no downward backflow region is generated in the central region of the gasification furnace body 2.

[0044] As shown in FIG. 5A, when a gasifying agent is introduced into the gasifier body 2 and a relatively strong swirl is applied, a backflow region is formed in the horizontal plane in the biomass introduction section where the raw material particles are introduced, and the gasifying agent and biomass fuel are mixed. On the other hand, with a relatively weak swirl as shown in FIG. 5B, a backflow region is not formed in the horizontal plane, and a swirling flow without a backflow occurs in the biomass introduction section with a flow velocity of 0 m / s or more. When a backflow region occurs as shown in FIG. 5A, the high-temperature gas after the gasification reaction flows around from above to the vicinity of the furnace wall (see FIG. 4A), but in FIG. 5B, there is no backflow region, and the gasifying agent (about 500°C) flows in the vicinity of the furnace wall as a swirling flow. For this reason, the temperature near the furnace wall is low as shown in FIG. 4B. From the above, it is preferable that the swirling flow formed by the gasifying agent introduced from the gasifying agent introduction pipe 5 has a relatively weak swirl number Sw of 0.1 or more and 0.25 or less.

[0045] Next, the inclination angle α of the gasifying agent injection pipe 5 will be considered. The angular momentum flow rate Gφ shown in equation (1) increases as the inclination angle α (see Figure 3) increases, because the radius r of the circle (called the virtual circle) with the gasifying agent injection direction (arrow A1 in Figure 3) as a tangent increases.

[0046] The radius r of the virtual circle can be expressed by equation (2). r = Rt × sinα (2)

[0047] The angular momentum flow Gφ is expressed by equation (3). Gφ = (4 places) × (momentum per one place of the gasification agent injection pipe 5) × (radius r of the imaginary circle) = 4 × mφ × uφ × Rt × sinα (3) Here, mφ indicates the mass flow rate per gasifying agent injection pipe, and uφ indicates the gasifying agent injection flow velocity (see FIG. 3).

[0048] The vertical momentum of the gasifier is expressed by equation (4). Gt = (vertical momentum of the lower part of the gasification furnace body 2) = mt × Ut (4) Here, mt indicates the mass flow rate at the lower part of the gasification furnace main body 2, and Ut indicates the upward flow velocity of the gasifying agent at the lower part of the gasification furnace main body 2. Note that in formula (4), the lower part of the gasification furnace main body 2 specifically means the position of the second cylindrical part 2e (FIG. 2).

[0049] The upward flow velocity Ut is determined so that the vertical flow velocity of the gasifying agent at the biomass inlet is equal to or greater than the maximum particle terminal velocity (gas flow velocity for suspending the maximum particle diameter contained in the biomass particles) required to suspend almost all of the biomass particles (particulate raw material) supplied, and is therefore a function of the maximum particle diameter. The mass flow rate mt is the sum of the amounts of oxygen and water vapor required for gasification. Therefore, from the relationship between equations (1), (3), and (4), the swirl number Sw can be calculated using the maximum particle diameter of the biomass particles and the inclination angle α.

[0050] Fig. 6 shows the relationship between the maximum particle size of the supplied biomass particles and the swirl number Sw, with the inclination angle α as a parameter. In the figure, the horizontal axis represents the maximum particle size [mm] of the biomass particles, and the vertical axis represents the swirl number Sw.

[0051] Since the smaller the maximum particle size of the biomass particles, the greater the power required for the mill to crush the biomass fuel, the maximum particle size of the biomass particles should be 5 mm or more, preferably 7 mm or more, and more preferably 8 mm or more. Therefore, as shown in Fig. 6, the inclination angle α at which the gasifying agent is injected from the gasifying agent injection pipe 5 is preferably 5° or more, and in order to set the swirl number Sw to 0.1 to 0.25, at which a relatively weak swirl occurs, the inclination angle α is preferably 50° or less. Furthermore, if the inclination angle α exceeds 50°, production becomes difficult and there is a risk of increased costs.

[0052] Next, using Figures 7A and 7B, the difference in effect between the case where there is no swirling as in Figure 4A (reference example) and the case where there is swirling as in Figure 4B (this embodiment) will be considered. In Figures 7A and 7B, the upper left diagram corresponds to (b) of Figure 4A and (b) of Figure 4B, the upper right diagram is a diagram simulating the density of the raw material particles (black circles) at the center position Z1 and the furnace wall position Z2 shown in the upper left diagram, and the lower diagram is a graph showing the flow rate Q, temperature T, flow velocity u, and density ρ from the center position Z1 to the furnace wall position Z2.

[0053] In the absence of swirling as shown in Figure 7A, the raw material particles fed into the gasifier body 2 fall towards the opposing wall surface, so the particle density inside the gasifier body 2 is higher on the furnace wall side. In areas with a large amount of raw material particles (furnace wall side), the gas temperature rises due to partial combustion of the raw material particles, so the temperature near the furnace wall rises. The flow rate of the gasifying agent in the direction of the central axis CL of the gasifier body 2 increases on the furnace wall side, where the temperature is higher, because the gas volume increases due to thermal expansion, so the flow rate in the direction of the central axis CL is also higher than in the center.

[0054] In contrast, when a relatively weak swirl is applied as in this embodiment shown in Fig. 7B, the raw material particles ride the swirl and the distribution in the cross-sectional direction of the gasifier body 2 becomes uniform. Therefore, the amount of heat generated by partial combustion of the raw material particles is also uniform in the cross-sectional direction of the gasifier body 2. On the other hand, a flow component of the gasifying agent in the circumferential direction is generated by the swirl, and the flow velocity is faster near the furnace wall. Therefore, the flow rate of the gasifying agent, which has a low temperature, is higher near the furnace wall than near the center, and the gas temperature is lower than near the center. By applying a relatively weak swirl due to this action, the gas temperature in the gasification furnace main body 2 can be lowered at the furnace wall portion.

[0055] In addition, in the case of a relatively strong swirl with a swirl number Sw exceeding 0.25, a backflow occurs in the center portion (see FIG. 5A). This results in a relative decrease in the flow rate of the gasifying agent flowing near the furnace wall of the gasification furnace body 2. This reduces the effect of lowering the temperature by the gas flow near the furnace wall as in this embodiment, and as a result, it is considered that the temperature near the furnace wall increases.

[0056] In this embodiment, the vicinity of the furnace wall of the gasification furnace body 2 means within at least 0.1 Rt from the furnace wall. The high temperature region occurring in the center of the gasification furnace body 2 rather than in the vicinity of the furnace wall means a region within at least 0.2 Rt from the central axis CL of the gasification furnace body 2.

[0057] The effects of the present embodiment described above are as follows. The gasification agent introduction pipe 5 creates a swirling flow in the gas flowing inside the gasification furnace body 2. By creating a swirling flow, a circumferential gas flow is formed along the inner wall surface of the gasification furnace body 2, which makes it possible to suppress partial combustion of the raw material particles (biomass fuel) introduced from the screw feeder 3 near the furnace wall. This makes it possible to prevent as much as possible the partial combustion of the biomass fuel near the furnace wall, which would result in the ash of the biomass fuel having a melting point lower than the combustion temperature melting and causing clinker to adhere to the furnace wall.

[0058] When the swirling flow is strong, a vertically downward backflow may occur in the central region including the central axis CL on the horizontal plane at the height position of the screw feeder 3 where the biomass fuel is fed. Therefore, a swirling flow is formed by the gasification agent feeding section so that the vertical component of the gas flow velocity is 0 m / s or more over the entire horizontal plane. This makes it possible to prevent as much as possible the relative decrease in gas flow velocity near the furnace wall and the rise in temperature caused by the backflow in the central region.

[0059] By feeding the gasifying agent at an inclination angle α of 5° or more and 50° or less with respect to a reference line BS passing through the central position 5a of the raw material particles and the central axis CL, it is possible to obtain a swirling flow strength in the desired range that does not cause backflow in the central region.

[0060] By setting the swirl number Sw of the swirling flow formed by the gasifying agent injection pipe 5 to be 0.1 or more and 0.25 or less, it is possible to obtain the strength of the swirling flow in a desired range in which no backflow occurs in the central region.

[0061] The gasifier 1 of the present disclosure is not limited to the gasifier for synthesizing liquid fuel as shown in this embodiment, but can also be applied to a gasifier for a chemical plant for obtaining desired chemical substances or a gasifier for power generation.

[0062] The biomass gasifier, the integrated gasification combined cycle power generation facility, and the method of operating the biomass gasifier described in the above-described respective embodiments can be understood, for example, as follows.

[0063] The biomass gasification furnace according to the first aspect of the present disclosure is a cylinder having a central axis (CL) in the vertical direction, and is equipped with a gasification furnace body (2) that gasifies biomass fuel inside, a biomass fuel input section (3) that inputs biomass fuel into the gasification furnace body (2), and a gasification agent input section (5) that is located below the biomass fuel input section (5) and inputs a gasification agent into the gasification furnace body (2) so that a swirling flow is formed around the central axis (CL).

[0064] The gasification agent feed section creates a swirling flow in the gas flowing inside the gasification furnace body. By creating a swirling flow, a circumferential gas flow is formed along the inner wall surface of the gasification furnace body, which makes it possible to suppress partial combustion of the biomass fuel fed from the biomass fuel feed section near the inner wall surface. This makes it possible to prevent as much as possible the partial combustion of the biomass fuel near the inner wall surface, which causes the ash of the biomass fuel, which has a melting point lower than the combustion temperature, to melt and form clinker on the inner wall surface. As the biomass fuel, for example, wood-based biomass fuel such as thinned wood, waste wood, driftwood, etc. can be used. As the gasifying agent, for example, oxygen (or air), water vapor, etc. are used.

[0065] In the biomass gasification furnace according to the second aspect of the present disclosure, in the first aspect, the gasifying agent input section (5) forms a swirling flow so that the vertical component of the gas flow velocity is 0 m / s or more over the entire horizontal plane at the height position of the biomass fuel input section (3).

[0066] When the swirling flow is strong, a vertically downward backflow may occur in the central area including the central axis on the horizontal plane at the height position of the biomass fuel input section. Therefore, a swirling flow is formed by the gasification agent input section so that the vertical component of the gas flow velocity is 0 m / s or more over the entire horizontal plane. This makes it possible to prevent as much as possible the relative decrease in gas flow velocity near the inner wall surface and the rise in temperature due to the backflow in the central area.

[0067] In the biomass gasification furnace according to the third aspect of the present disclosure, in the first or second aspect, the gasifying agent feeding section (5) feeds the gasifying agent at an angle (α) of 5° or more and 50° or less with respect to a reference line (BS) passing through the feeding position (5a) and the central axis (CL).

[0068] By injecting the gasifying agent at an angle of 5° to 50° with respect to a reference line passing through the injection position and the central axis, it is possible to obtain a swirling flow strength in a desired range that does not cause a backflow in the central region.

[0069] In the biomass gasification furnace according to the fourth aspect of the present disclosure, in any one of the first to third aspects, the swirl number (Sw) of the swirling flow formed by the gasifying agent feeding section (5) is set to be 0.1 or more and 0.25 or less.

[0070] By setting the swirl number of the swirling flow formed by the gasifying agent injection section to be 0.1 or more and 0.25 or less, it is possible to obtain a swirling flow strength in a desired range in which no backflow occurs in the central region.

[0071] A liquid fuel production facility (10) according to one embodiment of the present disclosure includes a biomass gasification furnace described in any one of the first to fourth embodiments, and a liquid fuel synthesis facility that synthesizes liquid fuel from at least a portion of the product gas produced in the gasification furnace.

[0072] A method for operating a biomass gasification furnace according to one embodiment of the present disclosure is a method for operating a biomass gasification furnace comprising: a gasification furnace body (2) which is a cylinder having a central axis (CL) in the vertical direction and which gasifies biomass fuel inside; a biomass fuel input section (3) which inputs biomass fuel into the gasification furnace body (2); and a gasification agent input section (5) which is located below the biomass fuel input section (3) and inputs a gasification agent into the gasification furnace body (2), wherein a swirling flow is formed around the central axis by the gasification agent input section (5). [Explanation of symbols]

[0073] 1 Gasifier 2 Gasifier body 2a Main body 2b First tapered section 2c 1st cylinder part 2d Second taper section 2e 2nd cylinder part 3 Screw feeder (biomass raw material input section) 3a Electric motor 3b Cooling jacket 5 Gasification agent injection pipe (gasification agent injection section) 5a Feeding center position 10 Liquid fuel production equipment 11 Biomass raw material supply facility 12 Raw material supply line 15 Ash recovery facility 16 Gas purification equipment 17 Liquid fuel synthesis equipment 42 Air Separation Plant 46 Steam supply line 47 Oxygen Supply Line 49 First produced gas line 51 Dust collector 53 Second produced gas line

Claims

1. a gasification furnace body that is a cylindrical body having a central axis in the vertical direction and that gasifies the biomass material therein; a biomass feedstock input section for inputting biomass feedstock into the gasification furnace body; a gasifying agent charging section that is provided below the biomass material charging section and that charges a gasifying agent into the gasification furnace body so that a swirling flow is formed around the central axis; Equipped with The gasification agent charging section of the biomass gasification furnace forms a swirling flow so that the vertically upward component of the gas flow velocity is 0 m / s or more over the entire horizontal plane at the height position of the biomass material charging section.

2. 2. The biomass gasification furnace according to claim 1, wherein the gasifying agent charging section charges the gasifying agent at an angle of 5° to 50° with respect to a reference line passing through a charging position and the central axis.

3. 2. The biomass gasifier according to claim 1, wherein the swirl number of the swirling flow formed by the gasifying agent charging section is 0.1 or more and 0.25 or less.

4. A biomass gasification furnace according to any one of claims 1 to 3; a liquid fuel synthesis facility for synthesizing a liquid fuel from at least a portion of the product gas generated in the gasification furnace; A liquid fuel production facility equipped with:

5. a gasification furnace body that is a cylindrical body having a central axis in the vertical direction and that gasifies the biomass material therein; a biomass feedstock input section for inputting biomass feedstock into the gasification furnace body; a gasifying agent charging section that is provided below the biomass material charging section and that charges a gasifying agent into the gasification furnace body, A method for operating a biomass gasification furnace, wherein the gasification agent feeding section forms a swirling flow around the central axis so that the vertically upward component of the gas flow velocity is 0 m / s or more across the entire horizontal plane at the height position of the biomass raw material feeding section.

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