Vertical reactor

Abstract

To provide a vertical reactor capable of gasificating in a temperature range lower than a phase transition temperature range, and having an inexpensive device configuration.SOLUTION: A vertical reactor 1 for burning and gasificating by contacting a raw material biomass derived from a silicic acid plant with oxygen and steam includes: a fluidized medium layer 2 provided at a bottom part of the reactor 1; a first gas-feeding mechanism 3 for feeding an oxygen-containing gas to the fluidized medium layer 2 to form a jet flow bed; a raw material-feeding mechanism 6 for feeding a raw material to the jet flow bed; and a first water-feeding mechanism 5 for feeding water to the fluidized medium layer 2, where the biomass is subject to heat decomposition with a steam obtained by vaporizing the water fed from the first water-feeding mechanism 5, and a reaction temperature is controlled.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a vertical reactor for producing amorphous silica, which is a raw material for various industrial uses, from biomass derived from silicic acid plants. [Background technology]

[0002] Patent Document 1 proposes a method and apparatus for producing amorphous silica that uses biomass derived from silicic acid plants as a raw material, and that can recover energy while obtaining high-purity, high-quality silica.

[0003] The method for producing amorphous silica includes a gasification step of pyrolyzing and gasifying biomass, and a calcination step of calcining biomass residue generated in the gasification step. The gasification step needs to gasify at a temperature range lower than the phase transition temperature range in which amorphous silica crystallizes. This is because, when silica obtained from biomass crystallizes, it becomes a harmful substance such as cristobalite, and its subsequent use is restricted.

[0004] Patent Document 2 discloses an example of a vertical reactor in which the above-mentioned gasification step is carried out. The reactor is formed by vertically arranging a biomass supply part derived from a silicic acid plant, a steam supply part, a first region for fluidizing the biomass supplied from the biomass supply part in an entrained bed formed by the steam supplied from the steam supply part, and a second region into which the gas generated in the first region flows, in the gas flow direction. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2020-040861 A [Patent Document 2] JP 2016-190887 A Summary of the Invention [Problem to be solved by the invention]

[0006] In order to lower the combustion temperature of the gas below the above-mentioned phase transition temperature range, a heat exchanger consisting of an annular coil is installed in the second area, and the steam obtained by heating water injected as a heat medium in the heat exchanger can be used as the steam supplied from the water vapor supply section.

[0007] However, the annular coil that makes up the heat exchanger falls under the category of a boiler under the Industrial Safety and Health Act, and so there was an issue that the equipment would be very expensive in order to meet strict safety standards.

[0008] An object of the present invention is to provide a vertical reactor capable of gasifying in a temperature range lower than the phase transition temperature range and having an inexpensive device configuration. [Means for solving the problem]

[0009] In order to achieve the above-mentioned object, a first characteristic configuration of the vertical reactor according to the present invention is that it is a vertical reactor in which a raw material, biomass derived from a silicic acid plant, is combusted and gasified by contacting it with oxygen and water vapor, and is equipped with a fluidized medium bed provided at the bottom of the reactor, a first gas supply mechanism for supplying an oxygen-containing gas to the fluidized medium bed to form an entrained bed, a raw material supply mechanism for supplying the raw material to the entrained bed, and a first water supply mechanism for supplying water to the fluidized medium bed.

[0010] By supplying oxygen-containing gas from the first gas supply mechanism, a spouted bed is formed in which the fluidized medium constituting the fluidized medium layer flows. By supplying biomass derived from a silicic acid plant to the spouted bed supplied from the raw material supply mechanism, the biomass is heated while flowing together with the fluidized medium in the spouted bed. At this time, the water supplied to the fluidized medium layer from the first water supply mechanism is heated to steam, and the combustion and gasification of the biomass proceeds. By adjusting the amount of water supplied by the first water supply mechanism, the combustion temperature and gasification temperature of the biomass can be appropriately adjusted. For example, it is possible to gasify at a temperature range lower than the phase transition temperature range in which amorphous silica crystallizes, and by reducing the supply amount of oxygen-containing gas and increasing the proportion of water-gas reaction, it is possible to adjust so that black silica with a high carbon content is obtained, and by increasing the supply amount of oxygen-containing gas and focusing on the combustion reaction, it is possible to adjust so that white silica with a low carbon content is obtained.

[0011] The second characteristic feature of the present invention is that, in addition to the first characteristic feature described above, the first water supply mechanism supplies water to the fluidized medium layer above a position where gas is supplied by the first gas supply mechanism.

[0012] The oxygen-containing gas supplied from the first gas supply mechanism to the fluidized bed forms a spouted bed to properly combust the biomass, and water is supplied from above from the first water supply mechanism, thereby effectively adjusting the combustion temperature while maintaining the spouted state.

[0013] The third characteristic feature of the present invention is that, in addition to the first or second characteristic feature described above, a second gas supply mechanism is provided for supplying an oxygen-containing gas to a space above the fluidized medium layer.

[0014] The combustion gas generated by burning the biomass in the entrained bed formed by the fluidized bed rises in the internal space of the reactor together with the incinerated biomass. The temperature of the combustion gas can be suitably adjusted by supplying oxygen gas from the second gas supply mechanism to the combustion gas flowing above the fluidized bed.

[0015] The fourth characteristic feature of the present invention is that, in addition to the third characteristic feature described above, a second water supply mechanism that injects water into a space above the second gas supply mechanism is provided.

[0016] The water injected from the second water supply mechanism can adjust the combustion temperature to a temperature range lower than the phase transition temperature range at which amorphous silica crystallizes.

[0017] The fifth characteristic configuration of the same is, in addition to the third characteristic configuration described above, that the reactor comprises a first cylindrical portion, a second cylindrical portion located above the first cylindrical portion and having a larger diameter than the first cylindrical portion, and an expanding cylindrical portion connecting an upper end of the first cylindrical portion and a lower end of the second cylindrical portion and gradually expanding in diameter from the first cylindrical portion to the second cylindrical portion, the spouted bed is formed in the first cylindrical portion, and the second gas supply mechanism is installed in the second cylindrical portion.

[0018] In the entrained bed formed in the first tube section, the biomass is burned mainly by a combustion reaction, and the combustion gas and combustion residue containing amorphous silica rise inside the reactor. The rising speed of the combustion gas slows as it passes through the entrained tube section, and some of the heavy unburned biomass and combustion residue fall toward the entrained bed and are further burned in the entrained bed. The combustion state of the combustion gas and combustion residue of the light unburned biomass, including the water gas and biomass being incinerated that have passed through the entrained tube section, is adjusted by the oxygen-containing gas supplied from the second gas supply mechanism.

[0019] The sixth characteristic configuration is that, in addition to the fifth characteristic configuration described above, the second gas supply mechanism is provided with a nozzle that injects oxygen-containing gas so that the gas injection center is directed toward the inner wall of the expanding cylindrical portion.

[0020] Because the flow velocity of the combustion gas decreases in the expanded diameter section, the flow of some of the heavy unburned biomass and combustion residues tends to be biased toward the inner wall of the expanded diameter section rather than the center of the reactor. The oxygen-containing gas injected from the nozzle of the second gas supply mechanism is directed toward the inner wall of the expanded diameter section, causing the unburned biomass pieces to fall toward the first cylindrical section, and as a whole, it becomes possible to effectively promote stirring and mixing with the oxygen-containing gas.

[0021] A seventh characteristic feature of the present invention is that, in addition to the first or second characteristic feature described above, combustion ash containing amorphous silica is discharged from the reaction furnace together with the combustion exhaust gas.

[0022] Biomass derived from silicic acid plants is combusted and gasified by contacting it with oxygen and water vapor, and combustion ash containing amorphous silica is discharged from the reactor together with the combustion exhaust gas. Effect of the Invention

[0023] As described above, according to the present invention, it is possible to provide a vertical reactor capable of gasification in a temperature range lower than the phase transition temperature range and having an inexpensive device configuration. [Brief description of the drawings]

[0024] [Figure 1] FIG. 1 is an explanatory diagram of a vertical reactor according to the present invention. [Diagram 2] FIG. 4A is an explanatory diagram of a plan view of a first gas supply mechanism, and FIG. 4B is a cross-sectional view of a main part of the first gas supply mechanism. [Diagram 3] 1A is a bottom view of the second gas supply mechanism, and FIG. 1B is a cross-sectional view taken along the line AA of FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0025] The vertical reactor according to the present invention will be described below. The reactor is a vertical reactor in which the raw material, biomass derived from silicic acid plants, is combusted and gasified by contacting it with oxygen and water vapor. As the biomass derived from silicic acid plants, rice husks, rice straw, wheat straw, bamboo, corn, sugarcane, thin grass, horsetail, etc. are targeted. In the following embodiment, rice husks are used.

[0026] [Reactor configuration] As shown in FIG. 1, the vertical reactor 1 includes a first cylindrical portion 1A with a bottom, a second cylindrical portion 1C located above the first cylindrical portion 1A and having a larger diameter than the first cylindrical portion 1A, and an expanding cylindrical portion 1B that connects the upper end of the first cylindrical portion 1A to the lower end of the second cylindrical portion 1C and gradually expands in diameter from the first cylindrical portion 1A to the second cylindrical portion 1C. An exhaust port 1E is formed at the top 1D of the second cylindrical portion 1C. The size and processing amount of the reactor 1 are not particularly limited and can be set appropriately. In this embodiment, the inner diameter of the first cylindrical portion 1A is set to 75% of the inner diameter of the second cylindrical portion 1C.

[0027] A fluidized medium layer 2 is provided at the bottom of the first cylindrical portion 1A, and a first gas supply mechanism 3, a gas burner 4, a first water supply mechanism 5, and a raw material supply mechanism 6 are provided on the side wall of the first cylindrical portion 1A. A second gas supply mechanism 7 is provided at the top of the expanded diameter cylindrical portion 1B, and a second water supply mechanism 8 is provided on the upper side wall thereof.

[0028] The fluidized medium layer 2 is filled with silica sand having a small particle size, which serves as a fluidized medium for biomass. In this embodiment, the silica sand is filled so that the upper surface of the fluidized medium layer 2 is formed above the installation height of the first gas supply mechanism 3 when the fluidized medium layer 2 is in a stationary state. When the reactor 1 is started up, the oxygen-containing gas supplied from the first gas supply mechanism 3 fluidizes the silica sand to form a spouted bed, and the gas burner 4, which is a supporting burner, is ignited to heat the spouted bed. When the temperature of the spouted bed reaches the natural temperature of the biomass (300 to 400°C when the biomass is rice husks), the gas burner 4 is extinguished, and biomass is supplied from the raw material supply mechanism 6.

[0029] In the entrained bed, the high-temperature fluidized silica sand and biomass are agitated and mixed, and the carbon components contained in the biomass are combusted by the oxygen-containing gas supplied from the first gas supply mechanism 3. At this time, the temperature of the entrained bed is adjusted to approximately 500 to 600°C by the first water supply mechanism 5 supplying water to the fluidized medium layer 2 from above the gas supply position of the first gas supply mechanism 3, and water vapor generated by vaporization of water is supplied to the entrained bed and the biomass burning in the space above it.

[0030] The biomass gasification reaction is driven by the water-gas reaction of the biomass between the hot steam and the carbon. C+H 2 O → CO+H 2 C+2H 2 O → CO 2 +2H 2 The water-gas reaction is an endothermic reaction, and the temperature of the spouted bed is adjusted to about 500-600°C by combining with the heat of vaporization of water.

[0031] The rates of the water-gas reaction and the combustion reaction are adjusted, and the combustion temperature of the biomass in the entrained bed is regulated, by the amount of oxygen-containing gas supplied from the first gas supply mechanism 3 and the amount of water supplied from the first water supply mechanism 5. For example, a control circuit may be provided that maintains the amount of oxygen-containing gas supplied from the first gas supply mechanism 3 at a constant amount at which the entrained bed can be formed, while controlling the amount of water supplied from the first water supply mechanism 5 based on the temperature of the entrained bed detected using a temperature sensor such as a thermocouple.

[0032] The combustion gas generated by the water-gas reaction and the combustion reaction, the combustion residue (amorphous silica), and the unburned biomass rise from the first cylindrical section 1A into the internal space of the reactor 1, and their ascending speed is suppressed as they pass through the expanding cylindrical section 1B. Some of the heavy unburned biomass and amorphous silica fall along the inner wall of the expanding cylindrical section into the first cylindrical section 1A and are further combusted in the entrained bed.

[0033] The water gas and unburned biomass that pass through the expanded diameter tube section 1B are sprayed from the second gas supply mechanism 7 installed in the second tube section 1C, and are guided by the flow of oxygen-containing gas toward the inner wall of the expanded diameter tube section 1B and fall into the first tube section 1A. The water gas and unburned biomass that rise to the second tube section 1C are stirred and mixed by the oxygen-containing gas, promoting the combustion reaction.

[0034] The combustion state of the combustion gas and amorphous silica is adjusted by the amount of oxygen-containing gas supplied from the second gas supply mechanism 7 and the amount of water supplied from the second water supply mechanism 8 provided above it. In other words, the temperature rise of the combustion gas due to the above-mentioned combustion reaction, the heat absorption due to the vaporization of water, the heat absorption due to the water-gas reaction caused by the water vapor obtained by vaporization of water, and the heat absorption due to the water-gas shift reaction (CO+H 2 O ⇔ CO 2 +H 2 Due to the heat generated by the combustion gas supply, and the cooling effect of the combustion gas by the water supply, the temperature of the combustion gas in the second cylindrical portion 1C is adjusted so that it is combusted or gasified in the temperature range of 700 to 800°C, which is lower than the phase transition temperature range at which amorphous silica crystallizes.

[0035] For example, a control circuit may be provided that controls the amount of oxygen-containing gas supplied from the second gas supply mechanism 7 so that the temperature in the vicinity of the second gas supply mechanism 7 detected using a temperature sensor such as a thermocouple is at least 600°C or higher, and controls the amount of water supplied from the second water supply mechanism 8 so that the temperature in the vicinity of the top 1D of the second cylindrical portion 1C detected using a temperature sensor such as a thermocouple does not exceed 800°C.

[0036] When most of the carbon components contained in biomass are burned, silica, which is the main component of the combustion residue, takes on a white color, whereas when the carbon components contained in biomass remain, silica, which is the main component of the combustion residue, takes on a black color.

[0037] White silica is effectively utilized in industrial materials such as a raw material for white cosmetics, an adsorbent, and an additive for white paints and resins, and in agricultural materials such as fertilizers for adding silica to crops, while black silica is effectively utilized in industrial materials such as a raw material for black cosmetics, an adsorbent, and an additive for black paints and resins, and an additive for tires, and in agricultural materials such as fertilizers for adding silica and carbon to crops.

[0038] In this specification, white silica refers to amorphous silica in which the proportion of carbon contained in the amorphous silica is less than 5% by weight and which has a white or whitish appearance, and black silica refers to amorphous silica in which the proportion of carbon contained in the amorphous silica is more than 5% by weight and which has a black or blackish appearance.

[0039] The combustion gas in the second cylindrical section 1C and the combustion residue, namely amorphous silica, flow out from the exhaust port 1E into the exhaust pipe 9, where they are guided to a cyclone 10 where they are separated from the combustion exhaust gas and collected. The combustion exhaust gas from which the amorphous silica has been separated is subjected to secondary combustion in a secondary combustion facility 11 and then released into the atmosphere.

[0040] [Structure of raw material supply mechanism] The raw material supply mechanism 6 is composed of a screw conveyor mechanism equipped with a cylindrical casing and a screw blade housed in the cylindrical casing, and the tip side of the casing is flange-connected to the side wall below the enlarged diameter cylindrical portion 1B of the reactor 1. Although not shown, a hopper equipped with a raw material quantitative supply mechanism is provided at the base end side of the casing.

[0041] The biomass filled in the hopper is fed to the screw conveyor mechanism by the material feed mechanism, and then transported inside the casing by the screw blades in a compact manner and fed into the reactor 1. Below, we will explain the case where a large amount of rice husks generated after hulling unhulled rice produced by farmers is used as the biomass derived from silicic acid plants.

[0042] [Configuration of the first gas supply mechanism] The first gas supply mechanism 3 is configured with a header pipe 32 arranged on the lower lateral side of the reactor 1, and a plurality of aeration pipes 34 with a circular cross section connected to the header pipe 32 in a parallel orientation to each other. An air supply pipe is connected to the header pipe 32, and compressed air is supplied from a compressor or a blower fan 30. A flow rate adjustment valve 31 is provided in the air supply pipe so that the amount of air supplied can be adjusted. Although air is used as the oxygen-containing gas, it is not limited to air, and oxygen-enriched gas or the like can also be used.

[0043] 2(a) and 2(b) show an example of the first gas supply mechanism 3. The first gas supply mechanism 3 includes a header pipe 32 disposed on the lower lateral side of the reactor 1, and a plurality of air diffuser pipes 34 connected to the header pipe 32 in a parallel orientation. An air supply pipe is connected to the header pipe 32, and air is supplied to each air diffuser pipe 34 via the header pipe 32.

[0044] Each of the air diffuser pipes 34 is supported by an attachment 33 having an arc-shaped cross section that is aligned along the lower peripheral wall of the reactor 1. The attachment 33 is formed in a shape that covers an arc-shaped cutout formed in the lower side wall of the reactor 1, and by fixing the attachment 33 to the side wall of the reactor 1 with the tip side of each of the air diffuser pipes 34 inserted into the reactor 1, the multiple air diffuser pipes 34 are fixed to the reactor 1 in a parallel orientation.

[0045] The air diffuser 34 is small in diameter and consists of many pieces so that the rice husks supplied from the raw material supply mechanism 6 are stirred and burned uniformly within any plane perpendicular to the vertical axis of the reactor 1 without creating localized high temperature areas.

[0046] The air diffuser 34 is formed with compressed air outlets 34H facing two directions, inclined obliquely downward at an angle θ with respect to the horizontal direction. The mixed gas discharged from the outlets 34H toward the bottom of the reactor 1 blows the silica sand upward to form a spouted bed, and uniformly stirs the rice husks supplied from the raw material supply mechanism 6. The angle θ is set in the range of 30° to 60°, preferably 40° to 50°, centered on an angle of 45° downward from the horizontal direction. The configuration of the air diffuser 34 described above is merely a suggestion, and the diameter and pitch of the outlets 34H, the value of the angle θ, and the like may be set appropriately.

[0047] The flow rate regulating valve 31 functions as an air ratio adjusting mechanism, and by adjusting the air ratio to the rice husks supplied from the raw material supply mechanism 6, it is possible to adjust whether the rice husks are subjected to a combustion reaction or a gasification reaction.

[0048] The air ratio adjustment mechanism adjusts the theoretical air ratio to the rice husks to either a first range in which the theoretical air ratio is greater than 1 so that the rice husks are primarily subjected to a combustion reaction, or a second range in which the theoretical air ratio is less than 1 so that the rice husks are primarily subjected to a gasification reaction.

[0049] By adjusting the air ratio to rice husks to a first range greater than the theoretical air ratio of 1, the rice husks can be combusted effectively, and by adjusting the air ratio to a second range less than the theoretical air ratio of 1 and contacting the rice husks with water vapor, the water-gasification reaction of the rice husks can be promoted.

[0050] [Configuration of the First Water Supply Mechanism] 1, the first water supply mechanism 5 includes a tubular header pipe 52 arranged around the lower part of the reactor 1 above the first gas supply mechanism 3, and a pair of water supply pipes 53 connected to the header pipe 52. A water supply pipe equipped with a flow rate control valve 51 is connected to the header pipe 52, and water is pressure-fed to the water supply pipe by a pump 50.

[0051] The water supply pipes 53 are arranged facing each other toward the vertical axis of the reactor 1 and are installed in a horizontal position. In this embodiment, a single-pipe nozzle with an inner diameter of 10 mm is used for the water supply pipe 53, and is attached so as to protrude about 20 mm inward from the inner wall of the first cylindrical portion 1A. The installation height of the water supply pipe 53 may be slightly below the upper surface of the fluidized medium layer 2 as long as it is near the upper surface of the fluidized medium layer 2. Injecting water into the sand layer can promote rapid temperature control by stirring and mixing, and supply of water vapor by evaporation.

[0052] [Configuration of the second gas supply mechanism] As shown in Fig. 1 and Fig. 3(a) and (b), the second gas supply mechanism 7 is composed of an air supply pipe 70 that is installed downward from an exhaust port 2B provided at the furnace top 2A of the reactor 1, and an annular header pipe 72 with a circular cross section that is connected to the lower end of the air supply pipe 70, and a plurality of first nozzles N1 and a plurality of second nozzles N2 are formed in the header pipe 72 so as to be arranged in an annular shape at a predetermined pitch. A flow rate adjustment valve 71 is installed in the air supply pipe 70. The header pipe 72 is installed at a position above the enlarged diameter cylindrical portion 1B at the lower part of the second cylindrical portion 1C.

[0053] The first nozzle N1 and the second nozzle N2 are configured as openings that are formed on a vertical plane that includes the center O1 of the annular header pipe 72 and the formation positions of each nozzle, so as to be inclined at a predetermined inclination angle θ1, θ2, respectively, with respect to a vertical line V that passes through the center O2 of the cross section of the header pipe 72.

[0054] Therefore, the oxygen-containing gas is injected from the first nozzle N1 in the direction of the first inclination angle θ1 toward the center side downward of the reactor 1 with respect to the vertical line V, and the oxygen-containing gas is injected from the second nozzle N2 in the direction of the second inclination angle θ2 toward the opposite side downward of the reactor 1 with respect to the vertical line V, that is, toward the nearest downward inner wall. The second inclination angle θ2 is set to a value smaller than the first inclination angle θ1. Note that a cylindrical body may be installed so as to protrude from each opening, and the first nozzle N1 and the second nozzle N2 may be constituted by the cylindrical body. The second nozzle N2 is a nozzle that injects the oxygen-containing gas so that the injection center of the gas is directed toward the inner wall of the expanded diameter cylindrical portion 1B.

[0055] Of the combustion gases flowing from the first cylindrical portion 1A to the second cylindrical portion 1C of the reactor 1, the combustion gas flowing along the side wall (inner wall) of the enlarged diameter cylindrical portion 1B is mixed with the oxygen-containing gas supplied from the second nozzle N2. Of the gases flowing from the first cylindrical portion 1A to the second cylindrical portion 1C of the reactor 1, the combustion gas flowing toward the center away from the side wall (inner wall) of the enlarged diameter cylindrical portion 1B is mixed with the oxygen-containing gas supplied from the first nozzle N1. Together, unburned biomass pieces contained in the gas flowing into the second cylindrical portion 1C are dropped toward the first cylindrical portion 1A, and as a whole, it is possible to effectively promote stirring and mixing with the oxygen-containing gas.

[0056] The oxygen-containing gas sprayed from the second nozzle N2 is supplied from the second cylindrical portion 1C side toward the expanded diameter cylindrical portion 1B, so that the oxygen-containing gas is efficiently supplied to the gas flowing along the inner wall of the expanded diameter cylindrical portion 1B.

[0057] The diameter of the header pipe 72, i.e., the diameter from the center O1 of the header pipe 72 to the center O2 of the cross section of the header pipe 72, can be set appropriately according to the diameter of the reactor 1, and is preferably set in the range of 60 to 90% of the diameter of the second cylindrical portion 1C.

[0058] There are 36 first nozzles N1 and 36 second nozzles N2, each spaced 10° apart from the center O1, and the spacing between the first nozzles N1 and the second nozzles N2 is 5° apart from the center O1. The opening diameter of each of the first nozzles N1 and the second nozzles N2 is set to 5 mm.

[0059] The first inclination angle θ1 is preferably set in the range of 35°≦θ1≦55°, and more preferably in the range of 40°≦θ1≦50°. The second inclination angle θ2 is preferably set in the range of 0°<θ2≦22°, and more preferably in the range of 10°<θ2≦17.5°. By setting the first inclination angle θ1 and the second inclination angle θ2 in the above-mentioned ranges, it is possible to effectively promote stirring and mixing with the oxygen-containing gas as a whole, and it becomes possible to appropriately adjust the composition of the gas components.

[0060] [Configuration of the Second Water Supply Mechanism] 1, the second water supply mechanism 8 includes a tubular header pipe 82 arranged around the upper periphery of the reactor 1 above the second gas supply mechanism 7, and four water injection nozzles 83 connected to the header pipe 82. A water supply pipe equipped with a flow rate control valve 81 is connected to the header pipe 82, and water is pressure-fed to the water supply pipe by a pump 80.

[0061] The water injection nozzle 83 is composed of four filled cone nozzles evenly arranged around the vertical axis of the reactor 1, and is arranged to inject water horizontally toward the vertical axis of the reactor 1. The filled cone nozzle is a one-fluid nozzle with specifications of a spray diameter of 60 μm, a spray angle of 70°, and an initial water droplet velocity of 27.6 m / s (water droplet temperature of 20°C). These specifications are an example, and the nozzle is not limited to these specifications. The nozzle may also be arranged to inject water obliquely upward toward the vertical axis of the reactor 1. In this case, the injection direction is preferably within a range of 20°±15° with respect to the horizontal.

[0062] The water droplets sprayed from the water spray nozzle 83 evaporate while diffusing inside the furnace, and the amount sprayed is adjusted so that the internal temperature of the second cylindrical portion 1C is in the temperature range of 700 to 800°C, which is lower than the phase transition temperature range at which amorphous silica crystallizes.

[0063] [Evaluation test of the First Water Supply Mechanism] The results of a test carried out to verify the specific structure of the first water supply mechanism 5 will be described. In an evaluation test in which water was supplied directly into the fluidized bed material using a single-tube nozzle with an inner diameter of 10 mm, the reactor 1 was able to operate stably and continuously, the sand layer constituting the fluidized bed material layer 2 did not get wet, there were no problems with vaporization, and the temperature of the sand layer was stable at around 600°C. The first water supply mechanism 5 is not limited to a single pipe, and may be a nozzle that supplies water in the form of droplets, and the nozzle may be either a one-fluid nozzle or a two-fluid nozzle.

[0064] [Evaluation test of the second water supply mechanism] The results of a simulation carried out to verify the specific structure of second water supply mechanism 8 will be described. Using a filled-cone nozzle with specifications of a spray diameter of 60 μm, a spray angle of 70°, and an initial water droplet velocity of 27.6 m / s (water droplet temperature of 20° C.), water was sprayed from above the second gas supply mechanism 7 toward the center of the reactor 1 in two modes, the horizontal direction (mode A) and 30° upward (mode B), from four locations in the circumferential direction of the second cylindrical portion 1C. The evaporation state, temperature distribution, and CO concentration characteristics of the sprayed water droplets were evaluated.

[0065] Using general-purpose thermal fluid analysis software, a simulation was performed to evaluate the spray direction and installation position of the second water supply mechanism 8 based on an actual-scale three-dimensional thermal fluid analysis model corresponding to the reactor 1 described in the above-mentioned embodiment. In addition to the two modes A and B, the simulation also included, as a comparison, a simulation of an existing configuration in which a coil-type heat exchanger is used in the second cylindrical portion 1C instead of the second water supply mechanism 8 to control the combustion temperature.

[0066] As a result, in all of modes A, B and the comparative example, the rate of water droplet adhesion to the wall surface of the reactor 1 was 0%, the temperature distribution within the reactor 1 was below the crystallization temperature of amorphous silica, and the CO concentration distribution at the outlet of the reactor 1 was less than 100 ppm, confirming that an effect equivalent to that of the existing configuration in which a coil-type heat exchanger is used to control the combustion temperature instead of the second water supply mechanism 8 can be obtained.

[0067] The type, number, arrangement, spray locations, and spray directions of the water injection nozzles used in the second water supply mechanism 8 are not limited to those described above, and may be appropriately determined through testing or simulation.

[0068] In the above-described embodiment, the reactor 1 is equipped with the second gas supply mechanism 7 and the second water supply mechanism 8. However, it is also possible to operate the reactor 1 using a coil-type heat exchanger instead of the second water supply mechanism 8. For example, when the amorphous silica to be recovered as combustion ash is black silica having a high carbon content, it is also possible to eliminate the second gas supply mechanism 7 and the second water supply mechanism 8 and operate the reactor 1 only by supplying gas from the first gas supply mechanism 3 and water from the first water supply mechanism 5.

[0069] In the above-described embodiment, the reactor 1 was equipped with the first water supply mechanism 5, but it is also possible to eliminate the first water supply mechanism 5 by changing the amount or form of water supply from the second water supply mechanism 8 so that the water supplied from the second water supply mechanism 8 reaches the fluidized medium layer 2 and the second water supply mechanism 8 replaces the first water supply mechanism 5.

[0070] The above description is merely one specific example of the resource circulation device according to the present invention, and the scope of the present invention is not limited by this description. It goes without saying that the specific configuration of each part can be appropriately modified and designed within the scope of the effect of the present invention. [Explanation of symbols]

[0071] 1: Reactor 1A: 1st cylinder part 1B: Expanded diameter cylinder part 1C:Second cylinder part 2: Fluidized medium layer 3: First gas supply mechanism 4: Gas burner 5: 1st water supply mechanism 6: Raw material supply mechanism 7: Second gas supply mechanism 8:Second water supply mechanism 9: Exhaust pipe 10: Cyclone 11: Secondary combustion equipment

Claims

1. A vertical reactor in which biomass derived from silicic acid plants, which is a raw material, is combusted and gasified by contacting it with oxygen and water vapor, a bed of fluidized medium provided at the bottom of the reactor; a first gas supply mechanism for supplying an oxygen-containing gas to the fluidized bed to form a spouted bed; a raw material supply mechanism for supplying the raw material to the spouted bed; a first water supply mechanism for supplying water to the fluidized medium bed; A vertical reactor equipped with:

2. 2. The vertical reactor according to claim 1, wherein the first water supply mechanism supplies water to the fluidized medium bed above a position at which the first gas supply mechanism supplies gas.

3. 3. The vertical reactor according to claim 1, further comprising a second gas supply mechanism for supplying an oxygen-containing gas to a space above said fluidized medium layer.

4. 4. The vertical reactor according to claim 3, further comprising a second water supply mechanism for injecting water into a space above said second gas supply mechanism.

5. 4. The vertical reactor according to claim 3, wherein the reactor comprises a first cylindrical portion, a second cylindrical portion located above the first cylindrical portion and having a larger diameter than the first cylindrical portion, and an expanding cylindrical portion connecting an upper end of the first cylindrical portion and a lower end of the second cylindrical portion and gradually expanding in diameter from the first cylindrical portion to the second cylindrical portion, the spouted bed being formed in the first cylindrical portion, and the second gas supply mechanism being installed in the second cylindrical portion.

6. 6. The vertical reactor according to claim 5, wherein said second gas supply mechanism includes a nozzle for injecting the oxygen-containing gas so that the injection center of the gas is directed toward the inner wall of said enlarged diameter cylindrical portion.

7. 3. The vertical reactor according to claim 1, wherein combustion ash containing amorphous silica is discharged from said reactor together with combustion exhaust gas.

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