WO2021181560A1 - Method for manufacturing amorphous silica and apparatus for manufacturing amorphous silica - Google Patents

Method for manufacturing amorphous silica and apparatus for manufacturing amorphous silica Download PDF

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WO2021181560A1
WO2021181560A1 PCT/JP2020/010518 JP2020010518W WO2021181560A1 WO 2021181560 A1 WO2021181560 A1 WO 2021181560A1 JP 2020010518 W JP2020010518 W JP 2020010518W WO 2021181560 A1 WO2021181560 A1 WO 2021181560A1
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amorphous silica
biomass
gasification
firing
biomass residue
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PCT/JP2020/010518
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French (fr)
Japanese (ja)
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陽介 釜田
剛士 阿部
倉田　雅人
直人 谷
崇聖 森田
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株式会社クボタ
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Priority to CN202080095732.7A priority Critical patent/CN115244000A/en
Priority to PCT/JP2020/010518 priority patent/WO2021181560A1/en
Publication of WO2021181560A1 publication Critical patent/WO2021181560A1/en

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    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B33/00—Silicon; Compounds thereof
    • C01B33/113—Silicon oxides; Hydrates thereof
    • C01B33/12—Silica; Hydrates thereof, e.g. lepidoic silicic acid
    • C01B33/18—Preparation of finely divided silica neither in sol nor in gel form; After-treatment thereof

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  • the present invention relates to a method for producing amorphous silica and an apparatus for producing amorphous silica, which recovers energy from biomass derived from silicic acid plants such as rice husks and separates and recovers silica contained in the biomass in a high value-added state. ..
  • Patent Document 1 describes a method for producing granular silicic acid, which obtains white granular silicic acid by supplying water vapor at 1000 ° C. or lower to charcoal obtained by carbonizing rice husks and causing an aquatic gas reaction. It is disclosed.
  • Patent Document 2 develops a means for effectively utilizing the gasification residue remaining after recovering energy from rice husks containing a large amount of silicic acid by thermal decomposition treatment, and provides a recycling system for the gasification residue of rice husks completed in a paddy field. A system for recycling rice husk gasification residues has been proposed for the purpose of this.
  • the rice husk gasification residue circulation utilization system is a gasification furnace that thermally decomposes rice husks to obtain decomposition gas and gasification residue, and energy for converting the decomposition gas into an energy source such as electricity, heat, or liquid fuel.
  • This system is equipped with a conversion facility and a particle size adjusting facility for adjusting the particle size of the gasified residue, and sprays the gasified residue whose particle size has been adjusted as an adsorbent for pesticides for paddy rice to paddy fields after irrigation.
  • Patent Document 3 contains silicon oxide as a method for obtaining high-purity amorphous silica from organic wastes such as agricultural products, grass foods, and wood without using mineral acids such as sulfuric acid, hydrochloric acid, and nitrate.
  • a step of preparing the organic waste as a starting material a step of immersing the organic waste in a carboxylic acid aqueous solution having a hydroxyl group, a step of subsequently washing the organic waste with water, and further the organic waste.
  • a method for producing amorphous silica including a step of heating system waste in an air atmosphere has been proposed.
  • the method for producing granular silicic acid disclosed in Patent Document 1 is a method for producing granular silicic acid by carbonizing the charcoal obtained by carbonizing rice husks into water gas to remove carbon content.
  • the dry distillation gas generated when the gas was obtained was wasted without being recovered, and there was room for further improvement from the viewpoint of resource recovery. Further, the purity of the obtained granular silicic acid is 90%, which is not so high, so that there is a problem that the use is limited.
  • rice husks are used as biomass, biofuel is generated from the water gas obtained by supplying water vapor to the rice husks, and silica is recovered from the biomass residue and reused, it can be recycled very efficiently. You can build a system.
  • the temperature at the time of the water-gas shift reaction is set to a high temperature of about 950 ° C. in order to improve the gasification efficiency, and therefore, a part of silica contained in the biomass residue is set depending on the temperature. There was a risk that it would crystallize and become difficult to reuse.
  • the rice husk gasification residue recycling system disclosed in Patent Document 2 is a system in which silica contained in the gasification residue is exclusively used as an adsorbent for agricultural chemicals for paddy rice, and when silica is used for other purposes, its purity is high. It was necessary to devise a way to raise it.
  • Patent Document 3 The method for producing amorphous silica disclosed in Patent Document 3 requires not only a water treatment facility for post-treating treated water such as an aqueous carboxylic acid solution, but also the treated organic waste in an air atmosphere. There was room for further ingenuity from the viewpoint of economic efficiency due to energy loss during heat treatment.
  • an object of the present invention is a method for producing amorphous silica, which can efficiently recover energy and obtain high-purity and high-quality silica using a biomass derived from a silicic acid plant as a raw material.
  • the point is to provide an apparatus for producing amorphous silica.
  • the first characteristic configuration of the method for producing amorphous silica according to the present invention is a method for producing amorphous silica using biomass derived from a silicic acid plant as a raw material, and the biomass is used.
  • the point is that it includes a gasification step of pyrolyzing and gasifying, and a firing step of firing the biomass residue generated in the gasification step.
  • Biomass derived from silicic acid plants is thermally decomposed by the gasification step and recovered as fuel, and the remaining biomass residue is calcined to remove impurities such as carbon components remaining in the biomass residue, resulting in high purity. Silica is obtained.
  • the second feature configuration is that, in addition to the first feature configuration described above, the gasification step is a step of gasifying in a temperature range lower than the phase transition temperature range in which the amorphous silica crystallizes. be.
  • amorphous silica does not crystallize. Further, the carbon component itself is not crystallized or incorporated into silica, and high-purity silica can be obtained in a later firing step.
  • the third feature configuration is that, in addition to the second feature configuration described above, the gasification step is adjusted so that the residence time of the biomass residue is equal to or less than a predetermined time.
  • the residence time of the biomass residue By adjusting the residence time of the biomass residue, the probability of crystallization of silica contained in the biomass residue can be reduced, and the probability that the carbon component itself crystallizes and is incorporated into silica can be reduced. As a result, high-purity silica can be obtained in a later firing step.
  • the fourth characteristic configuration is that, in addition to the above-mentioned second or third characteristic configuration, a fuel generation step of generating fuel from the gas obtained in the gasification step is provided.
  • the application as fuel can be expanded.
  • the fifth characteristic configuration includes, in addition to any of the first to fourth characteristic configurations described above, a pulverization step for pulverizing the biomass residue generated in the gasification step before the execution of the calcination step. There is a point.
  • the sixth characteristic configuration is, in addition to any of the first to fifth characteristic configurations described above, the firing step includes a first firing step in which the biomass residue is fired in a carbon combustion temperature range for a predetermined time. The point is that the first firing step is followed by a second firing step in which firing is performed in a temperature range lower than the phase transition temperature range for a predetermined time.
  • the carbon component contained in the biomass residue can be efficiently burned to remove the carbon-derived black component, and the temperature range is lower than the phase transition temperature range.
  • the second firing step of firing for a predetermined time impurities can be removed and the purity can be increased without causing crystallization of silica.
  • the first characteristic configuration of the amorphous silica production apparatus is the production of amorphous silica used in the method for producing amorphous silica having any of the above-mentioned first to sixth characteristic configurations.
  • An apparatus that provides a gasification furnace that thermally decomposes and gasifies biomass containing silicic acid plants, and a separation mechanism that separates the biomass residue from a mixture of the thermal decomposition gas discharged from the gasifier and the biomass residue. The point is that the biomass residue separated by the separation mechanism is calcined to obtain amorphous silica.
  • Biomass containing silicic acid plants is thermally decomposed in a gasification furnace, the pyrolysis gas and biomass residue are separated by a centrifuge, and the biomass residue is calcined in a calcining furnace to obtain silica.
  • the second characteristic configuration is that, in addition to the first characteristic configuration described above, a crusher for crushing the biomass residue separated by the separation mechanism is further provided.
  • the biomass residue By crushing the biomass residue separated by the centrifuge with a crusher and adjusting the particle size, the biomass residue can be fired efficiently in the firing furnace.
  • the third characteristic configuration is the heat generated in the gasification furnace and the biomass residue separated by the separation mechanism in the subsequent stage of the gasification furnace. It is equipped with a reactor that produces fuel from decomposition gas.
  • the energy possessed by the biomass can be efficiently reused.
  • a method for producing amorphous silica and amorphous silica capable of efficiently recovering energy and obtaining high-purity and high-quality silica using silicic acid plant-derived biomass as a raw material. It has become possible to provide equipment for producing quality silica.
  • FIG. 1 is an explanatory diagram showing an example of a method for producing amorphous silica according to the present invention.
  • FIG. 2 is an explanatory diagram of a cascading furnace and an FT synthesis reactor constituting the BTL plant.
  • FIG. 3 is an explanatory diagram showing an example of an apparatus for producing amorphous silica.
  • FIG. 4 is an explanatory diagram showing another example of the device for producing amorphous silica.
  • FIG. 5A shows Experiment No. 3 is an explanatory diagram of the thermogravimetric analysis result of the gasified ash
  • FIG. 5B is an explanatory diagram of the thermogravimetric analysis result of the gasified ash under the basic conditions.
  • FIG. 6 is an explanatory diagram of the results of a low temperature combustion experiment on a biomass residue.
  • FIG. 7 is an explanatory diagram of the component analysis result of white ash.
  • FIG. 1 shows one aspect of the method for producing amorphous silica according to the present invention.
  • Rice produced by farmers is shipped to rice centers or stored in country elevators, and a large amount of rice husks after being hulled are brought into a BTL (Biomass To Liquid) plant as raw materials.
  • BTL Biomass To Liquid
  • the BTL plant is provided with a gasification furnace and an FT synthesis reactor, and the synthetic gas obtained by decomposing the paddy shell in the gasification furnace is supplied to the FT synthesis reactor (also referred to as “FT synthesis reactor”) for FT synthesis.
  • FT synthesis reactor also referred to as “FT synthesis reactor”
  • the generated biofuel is used as fuel for transportation and fuel for agricultural work, and the waste heat generated in the BTL plant is used as a heat source for heat retention such as horticultural facilities and hot springs. Further, the off-gas obtained by FT synthesis with the FT synthesis reactor is used for heat source utilization equipment such as a gas engine generator and a boiler, and the power generated by the heat source utilization equipment is used in the facility.
  • a part of the large amount of silica component contained in the residue of rice husks pyrolyzed in the gasification furnace is used as fertilizer in the field, and the rest is industrially used as a raw material such as an adsorbent.
  • FIG. 2 shows the basic configuration of the BTL plant 100.
  • the BTL plant 100 removes solids such as ash, hydrogen sulfide gas, hydrogen chloride gas, ammonia and the like from the gasification furnace 10 that generates synthetic gas that is a raw material for liquid fuel from biomass and the generated synthetic gas. It includes a gas purification device 20 equipped with a cyclone, a scrubber, an activated charcoal adsorption tower, and the like, and an FT synthesis reactor 30 that synthesizes fuel from synthetic gas purified through the gas purification device 20.
  • a gas purification device 20 equipped with a cyclone, a scrubber, an activated charcoal adsorption tower, and the like
  • an FT synthesis reactor 30 that synthesizes fuel from synthetic gas purified through the gas purification device 20.
  • Gasifier 10 the furnace temperature is at a high temperature of 500 ° C. or higher 1000 ° C. or less, and a reaction tower biomass and reduced heating with steam or superheated steam to produce a synthesis gas (H 2, CO).
  • steam and biomass heated to about 500 ° C. at normal pressure by high-frequency heating or the like undergo a water-gas reaction or a water-gas shift reaction inside the reaction tower, and are exhausted from the exhaust port at the top of the reaction tower to open the exhaust pipe. Then, it is guided to the gas purification device 20.
  • the water gas reaction occurs mainly in the lower part of the reaction column, and the water gas shift reaction occurs mainly in the process of ascending the reaction column.
  • the gas purification device 20 is provided with an attracting blower, the inside of the reaction tower is maintained at a negative pressure, and the gas generated in the reaction tower is attracted to the gas purification device 20 for purification.
  • the biomass supply device is composed of a screw conveyor mechanism having a tubular casing whose one end is flanged below the reaction tower and screw blades housed in the tubular casing, and a fixed quantity supply mechanism on the other end side.
  • a screw conveyor mechanism having a tubular casing whose one end is flanged below the reaction tower and screw blades housed in the tubular casing, and a fixed quantity supply mechanism on the other end side.
  • a hopper Dry biomass such as rice husks crushed to about several mm is filled in the hopper, consolidated by screw blades, and put into the reaction tower.
  • a jet bed in which biomass flows is formed inside the reaction tower by steam supplied from the tip of a nozzle of a steam supply unit provided below the biomass supply device.
  • the region where the jet bed is formed is the first region R1 where the water gas reaction is mainly performed. Further, a second region R2 in which the water-gas shift reaction is mainly performed is formed above the first region R1.
  • the water gas reaction is an endothermic reaction in which carbon monoxide CO and hydrogen H 2 are produced from solid carbon C and water vapor H 2 O, which are biomass, in a high temperature environment of 500 ° C. or higher. ..
  • an oxygen supply unit that supplies a small amount of oxygen gas or air to the reaction tower is provided, and the required reaction heat is given by burning a part of the biomass.
  • the water-gas shift reaction is an exothermic reaction in which carbon dioxide CO 2 and hydrogen H 2 are produced from carbon monoxide CO and water vapor H 2 O in a high temperature environment of about 800 ° C. .. CO + H 2 O ⁇ CO 2 + H 2
  • Syngas and char and ash generated from biomass in the first region R1 rise to the second region R2 on the downstream side in the gas flow direction, and the above-mentioned water-gas shift reaction is promoted.
  • the water vapor required for the water-gas shift reaction is supplied from the water vapor supply unit, and the water vapor that did not contribute to the water-gas reaction is consumed in the first region R1.
  • the synthetic gas obtained in the reaction tower is purified by the gas purification apparatus 20 in the subsequent stage, and after impurities are removed, it is heated and pressurized to a high temperature and high pressure via a heater and a compressor, and charged into the FT synthesis reactor 30. FT is synthesized.
  • FT synthesis is an abbreviation for Fischer-Tropsch synthesis, also called “FT method” or “FT reaction”, and refers to a series of synthetic reaction processes that synthesize liquid hydrocarbons from carbon monoxide and hydrogen using a catalytic reaction. ..
  • the syngas charged into the FT synthesis reactor 30 is charged into a solvent in which a catalyst is dispersed and synthesized into a desired hydrocarbon.
  • a catalyst is dispersed and synthesized into a desired hydrocarbon.
  • the ratio H 2 / CO of hydrogen to carbon monoxide is preferably about 2.
  • the ratio H 2 / CO of hydrogen to carbon monoxide is preferably about 1.
  • the ratio H 2 / CO of hydrogen and carbon monoxide needs to be adjusted, and this ratio is FT even when the same type of hydrocarbon is obtained. It also depends on the type of catalyst used in the synthesis.
  • the temperature at which the rice husks are thermally decomposed in the gasification furnace must be at least a temperature range lower than the phase transition temperature range in which the silica contained in the rice husks crystallizes, and the crystallization of silica has an effect on health. From the viewpoint, it is not suitable for industrial use. Even if it is amorphous silica, if it has low purity and contains carbon components, it will be colored black, so cosmetics such as foundations, food additives, pharmaceutical additives, resin additives, paint additives, rubber. It cannot be used for materials such as fillers, and its use is limited.
  • amorphous silica According to the method for producing amorphous silica according to the present invention, high-purity amorphous silica can be efficiently obtained while regenerating energy from rice husks.
  • Rice husks which are one of the agricultural wastes, are about 70% carbohydrates such as cellulose, hemicellulose, and lignin, about 15 to 20% silica, and most of the rest is water and contains a small amount of alkaline impurities. There is.
  • the present invention is preferably used when such biomass containing silica is regenerated as a resource. Therefore, the application of the present invention is not limited to rice husks, but biomass derived from silicic acid plants such as rice straw, straw, bamboo, corn, sugar cane, thin, and horsetail.
  • a method for producing amorphous silica using biomass derived from a siliceous plant as a raw material is a gasification step in which biomass is thermally decomposed in a gasification furnace and a firing process in which the biomass residue generated in the gasification step is fired in a firing furnace. Including steps.
  • the gasification step the biomass derived from the silicic acid plant is thermally decomposed into hydrogen and carbon monoxide and recovered as fuel, and the remaining biomass residue is calcined to remove impurities such as carbon components remaining in the biomass residue. It is removed to give high purity silica.
  • those adopting a process of supplying water vapor to biomass to cause a water gas reaction and a water gas shift reaction to generate a synthetic gas such as hydrogen gas or carbon monoxide gas are included in the biomass residue. It is preferable to carry out the water-gas shift reaction in a temperature range lower than the phase transition temperature range in which silica crystallizes, for example, a temperature range of 800 ° C. or lower. Since the water-gas shift reaction is carried out in a temperature range below the phase transition temperature range, amorphous silica does not crystallize. Further, the carbon component itself is not crystallized or incorporated into silica, and the carbon component is effectively removed in the subsequent firing step to obtain highly pure silica.
  • the flow time of the biomass residue that is, the time until the biomass residue in which the biomass charged into the reaction tower is incinerated by the water gas reaction flows out from the reaction tower toward the gas purification apparatus 20 is set to a predetermined time or less. It is preferable that the amount of water vapor supplied or the amount of oxygen gas mixed with water vapor is adjusted so as to be.
  • Biomass is thermally decomposed by water gas reaction while flowing by water vapor, and further water gas shift reaction occurs and biomass residue remains.
  • the residence time of the biomass residue is adjusted.
  • the probability of crystallization of silica contained in the biomass residue can be reduced, and the probability that the carbon component itself is crystallized and incorporated into silica can be reduced.
  • Such adjustment makes it possible to obtain high-purity silica in a later firing step.
  • biofuel generation step in which the gas obtained in the gasification step is used as a raw material for FT synthesis processing to generate biofuel, and the application as a fuel is expanded from the viewpoint of efficient use of energy. Can be done.
  • a pulverization step for pulverizing the biomass residue generated in the gasification step, so that impurities can be efficiently separated by calcination and silica having a uniform particle size can be obtained. This allows for the promotion and homogenization of whitening in the firing step.
  • a first firing step in which the biomass residue is fired in a carbon combustion temperature range for a predetermined time, and a temperature higher than the first firing temperature after the first firing step, and a temperature range lower than the phase transition temperature range for a predetermined time. It is preferable to include a second firing step for firing.
  • the carbon component contained in the biomass residue is efficiently burned to remove the black component derived from carbon by the first firing step of firing in a carbon combustion temperature range, specifically, a temperature range of 400 to 600 ° C. for a predetermined time. It is possible to remove impurities and increase the purity by the second firing step of firing for a predetermined time in a temperature range below the phase transition temperature range, specifically, a temperature range below 800 ° C. without causing crystallization of silica. Can be done.
  • the gasification step may employ a pyrolysis process in which the biomass is heated and carbonized in a low oxygen concentration atmosphere.
  • FIG. 3 shows an example of an apparatus for producing crystalline silica for using the above-mentioned method for producing amorphous silica.
  • the amorphous silica production apparatus separates the biomass residue from a gasification furnace that pyrolyzes and gasifies biomass containing silicic acid plants and a mixture of the pyrolysis gas and biomass residue discharged from the gasification furnace. It is equipped with a separation mechanism such as a centrifuge cyclone filter, a crusher for crushing the biomass residue separated by the separation mechanism, and a firing furnace for calcining the crushed biomass residue to obtain amorphous silica. ..
  • As the firing furnace an electric firing furnace, a gas firing furnace, or the like can be appropriately used.
  • the gasification furnace is composed of a jet bed furnace in which biomass is flowed by steam to cause a water gas reaction and a water gas shift reaction, and the biomass residue is separated from a mixture of pyrolysis gas and biogas residue discharged from the jet bed furnace by a separation mechanism. It is further equipped with a reactor that produces fuel from the produced pyrolysis gas.
  • Superheated steam generated by a boiler using fossil fuels such as kerosene or biomass, and oxygen gas generated by the oxygen generator PSA (Pressure Swing Adsorption) are put into the gasification furnace together with the biomass, and in the gasification furnace.
  • Biomass residue contained in the generated water gas reaction and water gas shift reaction is separated by a cyclone, crushed to a predetermined particle size by a crusher, charged into a firing furnace, and fired to obtain high purity.
  • Amorphous silica can be obtained.
  • the synthetic gas from which the biomass residue has been removed by the cyclone is led to a heat exchanger for air preheating, and then washed with a scrubber to remove ammonia gas, hydrogen chloride gas, and the like.
  • CO 2 is removed from the synthetic gas purified by the gas purification unit in the CO 2 adsorption tower, and the synthetic gas whose temperature has been raised and raised by the temperature riser and booster is charged into the FT synthesis reactor.
  • Oil is synthesized by the FT reaction and vaporized as a gas component, which is liquefied in a condenser to obtain a liquid fuel as a fuel.
  • the lower hydrocarbon gas that has passed through the condenser is used as off-gas for fuel of the gas generator.
  • FIG. 4 shows another example of a crystalline silica manufacturing apparatus for using the above-mentioned amorphous silica manufacturing method.
  • the configuration of producing amorphous silica by gasifying biomass as a raw material in a gasification furnace, crushing the biomass residue separated by a cyclone with a crusher, and firing in a firing furnace is the same as in FIG. It differs from FIG. 3 in that the synthetic gas that has passed through the cyclone is used as a fuel for a gas generator without FT synthesis.
  • silica that can be used as a raw material for cosmetics (foundation raw material) from rice husks.
  • the qualities required for silica as a raw material for cosmetics are amorphous, a particle size of about 10 ⁇ m, and a silica purity of 97% or more. If the silica purity is 97% or more, it can be evaluated that it is white and does not contain harmful substances.
  • the operating conditions of the gasifier are the upper temperature of the gasifier (operating condition 1), which is the temperature of the second region R2 (see FIG. 2) where the water-gas shift reaction is mainly performed, and the steam / carbon ratio (operating condition 2). ), Air / pure oxygen substitution rate (operating condition 3), and processing amount (operating condition 4), what will be the gasification rate, biomass residue composition, and particle size when changed with respect to the basic conditions? Was tested.
  • the basic conditions are the conditions under which biofuel can be obtained with maximum efficiency when FT synthesis is performed using biomass, the upper temperature of the gasifier is 950 ° C, the steam / carbon ratio is 1.7, and air / carbon.
  • the pure oxygen substitution rate is set to 0% (pure oxygen 100%), and the processing amount is set to 1 t / day.
  • the temperature of the first region R1 is set to about 500 to 600 ° C.
  • operating condition 1 was 800 ° C. (basic condition 950 ° C.)
  • operating condition 2 was 1.7 (basic condition 1.7)
  • operating condition 3 was 100% (basic condition 0%).
  • the biomass residue under the specific operating condition in which the operating condition 4 is set to 1 t / d (basic condition 1 t / d) is fired at 800 ° C.
  • the ash becomes white (specifically, light pink).
  • 600 ° C and 550 ° C it was found that the ash became almost white (specifically, ultra-light gray), and the test results under other operating conditions showed that the ash was gray or black-gray even under the same firing conditions. Only ash was obtained.
  • thermogravimetric analysis results are shown in FIGS. 5 (a) and 5 (b).
  • FIG. 5 (b) when the biomass residue gasified under the basic conditions is heated (calcined), there are two exothermic peaks of carbon combustion (time 41.55 min. And 44.13 min.).
  • FIG. 5 (a) Experiment No. In No. 3, it was found that the exothermic peak of carbon combustion became one (time 42.83 min.).
  • the ash after the combustion experiment was mainly silica and had a slightly flat shape, but it was not melted and the complicated structure derived from rice husks was maintained.
  • crystalline silica cristobalite 0.6%, quartz 0.3%) was identified although it was a trace amount.
  • combustion temperature rise rates There are two types of combustion temperature rise rates: rapid (put in the furnace at the set temperature) and low speed (heat up at 200 ° C / hour in the furnace), and the combustion temperature is 600 to 800 ° C [800 ° C or higher.
  • the temperature was set to between [Crystalize], and the burning time was set to a different time in 1-hour units of 1 to 5 hours.
  • the experimental results are shown in FIG.
  • the ash of the biomass residue gasified under the basic conditions (the upper temperature of the gasification furnace was 950 ° C.) was not whitened even when the heating rate, the combustion temperature, and the combustion time were changed.
  • the ash of the biomass residue (Samples Nos. 1 to 10) gasified under specific operating conditions (the upper temperature of the gasification furnace is 800 ° C., which is below the phase transition temperature range at which silica crystallizes) is whitened. It's easier. It is probable that due to the decrease in gasification temperature, silica did not crystallize and carbon did not carbonize and became flammable soft carbon.
  • sample No. As shown in the results of 2, 3, 6 and 8, it becomes easier to whiten by lowering the temperature rise rate of combustion, and combustion at 800 ° C. for 2 hours or more, 750 ° C. for 4 hours, and 700 ° C. for 5 hours. It was confirmed that the gasified ash was whitened by performing the above.
  • FIG. 7 the sample No.
  • the component analysis result for the white ash of No. 6 is shown. Due to low temperature combustion, the carbon (C) concentration of the white ash became 0.1% or less, and the silica (SiO 2 ) was highly purified to 97% or more. Further, as components other than silica, potassium (K), sodium (Na), calcium (Ca), iron (Fe), phosphorus (P) and the like were contained in a trace amount.
  • the water-gas shift reaction is carried out in a temperature range below the phase transition temperature range in which silica contained in the biomass residue crystallizes. It was confirmed that it is preferable that the amount of water vapor supplied or the amount of oxygen gas mixed with the water vapor is adjusted so that the flow time of the biomass residue is less than a predetermined time in the gasification step.
  • the firing step Before the firing step is executed, it is preferable to include a crushing step of crushing the biomass residue generated in the gasification step to about 5 to 15 ⁇ m.
  • the biomass residue In the firing step, the biomass residue is predetermined in the carbon combustion temperature range. It is preferable to include a first firing step of firing for a time and a second firing step of firing for a predetermined time in a temperature range equal to or lower than the phase transition temperature range after the first firing step.
  • Carbon contained in the biomass residue by slowly raising the temperature at 100 to 200 ° C./hour toward the temperature range of 400 to 600 ° C., which is the combustion temperature range of carbon, and holding the temperature at 400 to 600 ° C. for 2 to 3 hours.
  • the carbon-derived black component can be removed by efficiently burning the component, and then by heating at a high temperature of 700 to 800 ° C. for 1 to 3 hours, impurities are removed without causing crystallization of silica. Purity can be increased.
  • Gasifier 20 Gas purification device 30: FT synthesis reactor 100: BTL plant R1: 1st region R2: 2nd region

Abstract

Provided is a method for manufacturing amorphous silica using biomass derived from a silicicolous plant as a raw material, said method including: a gasification step for thermally decomposing and gasifying the biomass; and a firing step for firing a biomass residue produced in the gasification step. In the gasification step, the gasification is performed in a temperature range below the phase transition temperature range in which amorphous silica is crystallized.

Description

非晶質シリカの製造方法及び非晶質シリカの製造装置Amorphous silica manufacturing method and amorphous silica manufacturing equipment
　本発明は、籾殻などのケイ酸植物由来のバイオマスからエネルギー回収するとともに、バイオマスに含まれるシリカを付加価値の高い状態で分離回収する非晶質シリカの製造方法及び非晶質シリカの製造装置に関する。 The present invention relates to a method for producing amorphous silica and an apparatus for producing amorphous silica, which recovers energy from biomass derived from silicic acid plants such as rice husks and separates and recovers silica contained in the biomass in a high value-added state. ..
　特許文献１には、籾殻を乾留して得られるくん炭に１０００℃以下の水蒸気を供給して、水成ガス反応を生起することにより白色の粒状ケイ酸質を得る粒状ケイ酸質製造方法が開示されている。 Patent Document 1 describes a method for producing granular silicic acid, which obtains white granular silicic acid by supplying water vapor at 1000 ° C. or lower to charcoal obtained by carbonizing rice husks and causing an aquatic gas reaction. It is disclosed.
　特許文献２には、ケイ酸を多く含む籾殻から熱分解処理によってエネルギーを回収した後に残るガス化残渣の有効活用手段を開発し、水田地帯で完結する籾殻ガス化残渣の循環利用システムを提供することを目的とした籾殻ガス化残渣の循環利用システムが提案されている。 Patent Document 2 develops a means for effectively utilizing the gasification residue remaining after recovering energy from rice husks containing a large amount of silicic acid by thermal decomposition treatment, and provides a recycling system for the gasification residue of rice husks completed in a paddy field. A system for recycling rice husk gasification residues has been proposed for the purpose of this.
　当該籾殻ガス化残渣の循環利用システムは、籾殻を熱分解処理して、分解ガスとガス化残渣を得るガス化炉と、前記分解ガスを電気、熱または液体燃料等のエネルギー源に転換するエネルギー転換設備と、前記ガス化残渣の粒径を整える粒度調整設備とを具え、粒度調整された前記ガス化残渣を、水稲用農薬の吸着剤として潅水後の水田へ散布するシステムである。 The rice husk gasification residue circulation utilization system is a gasification furnace that thermally decomposes rice husks to obtain decomposition gas and gasification residue, and energy for converting the decomposition gas into an energy source such as electricity, heat, or liquid fuel. This system is equipped with a conversion facility and a particle size adjusting facility for adjusting the particle size of the gasified residue, and sprays the gasified residue whose particle size has been adjusted as an adsorbent for pesticides for paddy rice to paddy fields after irrigation.
　特許文献３には、硫酸、塩酸、硝酸などの鉱酸を使用せずに、農作物、草食物、木材などの有機系廃棄物から高純度の非晶質シリカを得る方法として、酸化ケイ素を含む有機系廃棄物を出発原料として準備する工程と、前記有機系廃棄物を、水酸基を有するカルボン酸水溶液中に浸漬する工程と、続いて前記有機系廃棄物を水洗処理する工程と、さらに前記有機系廃棄物を大気雰囲気中で加熱する工程とを備えた非晶質シリカの製造方法が提案されている。 Patent Document 3 contains silicon oxide as a method for obtaining high-purity amorphous silica from organic wastes such as agricultural products, grass foods, and wood without using mineral acids such as sulfuric acid, hydrochloric acid, and nitrate. A step of preparing the organic waste as a starting material, a step of immersing the organic waste in a carboxylic acid aqueous solution having a hydroxyl group, a step of subsequently washing the organic waste with water, and further the organic waste. A method for producing amorphous silica including a step of heating system waste in an air atmosphere has been proposed.
特公昭４９－３０３５３号公報Special Publication No. 49-30353 特開２００９－２３９６５号公報JP-A-2009-23965 ＷＯ２００８／０５３７１１号公報WO2008 / 053711
　特許文献１に開示された粒状ケイ酸質製造方法は、籾殻を乾留して得たくん炭を水性ガス化して炭素分を除去することで粒状ケイ酸質を製造する方法であるが、くん炭を得る際に生じる乾留ガスは回収されることなく無駄に排気されており、資源回収という観点で更なる改良の余地があった。また、得られた粒状ケイ酸質の純度も９０％と、それほど高くないために用途が限られるという問題もあった。 The method for producing granular silicic acid disclosed in Patent Document 1 is a method for producing granular silicic acid by carbonizing the charcoal obtained by carbonizing rice husks into water gas to remove carbon content. The dry distillation gas generated when the gas was obtained was wasted without being recovered, and there was room for further improvement from the viewpoint of resource recovery. Further, the purity of the obtained granular silicic acid is 90%, which is not so high, so that there is a problem that the use is limited.
　ところで、近年、バイオマスに水蒸気を供給して水性ガス反応及び水性ガスシフト反応が起こり、得られた水性ガスをＦＴ合成の原料として用いてバイオ燃料を生成するＦＴ合成技術が注目されている。 By the way, in recent years, FT synthesis technology for producing biofuel by supplying water vapor to biomass to cause a water gas reaction and a water gas shift reaction and using the obtained water gas as a raw material for FT synthesis has attracted attention.
　バイオマスとして籾殻などを採用し、籾殻などに水蒸気を供給して得られた水性ガスからバイオ燃料を生成するとともに、バイオマス残渣からシリカを回収して再利用すれば、非常に効率のよい再資源化システムを構築することができる。 If rice husks are used as biomass, biofuel is generated from the water gas obtained by supplying water vapor to the rice husks, and silica is recovered from the biomass residue and reused, it can be recycled very efficiently. You can build a system.
　しかし、このような再資源化システムでは、ガス化効率を高めるために水性ガスシフト反応時の温度が９５０℃前後の高温に設定されているので、当該温度によってバイオマス残渣に含まれるシリカの一部が結晶化して再利用が困難な状況になる虞があった。 However, in such a recycling system, the temperature at the time of the water-gas shift reaction is set to a high temperature of about 950 ° C. in order to improve the gasification efficiency, and therefore, a part of silica contained in the biomass residue is set depending on the temperature. There was a risk that it would crystallize and become difficult to reuse.
　また炭素成分自体が結晶化してシリカに取り込まれると、その後にバイオマス残渣を焼成しても炭素分を除去しきれず、シリカの純度が低下するとともに灰色がかったシリカとなる。そのため、何れの場合にも用途が制限されるという問題があった。 If the carbon component itself crystallizes and is incorporated into silica, the carbon content cannot be completely removed even if the biomass residue is subsequently fired, and the purity of the silica decreases and the silica becomes grayish. Therefore, there is a problem that the use is limited in any case.
　特許文献２に開示された籾殻ガス化残渣の循環利用システムでは、ガス化残渣に含まれるシリカを専ら水稲用農薬の吸着剤に用いるシステムであり、シリカを他の用途に用いる場合には、純度を上げるための工夫が必要となっていた。 The rice husk gasification residue recycling system disclosed in Patent Document 2 is a system in which silica contained in the gasification residue is exclusively used as an adsorbent for agricultural chemicals for paddy rice, and when silica is used for other purposes, its purity is high. It was necessary to devise a way to raise it.
　特許文献３に開示された非晶質シリカの製造方法では、カルボン酸水溶液などの処理水を後処理するための水処理設備が必要となるばかりか、処理後の有機系廃棄物を大気雰囲気中で加熱処理する際にエネルギー損失を来し、経済性の観点で更なる工夫の余地があった。 The method for producing amorphous silica disclosed in Patent Document 3 requires not only a water treatment facility for post-treating treated water such as an aqueous carboxylic acid solution, but also the treated organic waste in an air atmosphere. There was room for further ingenuity from the viewpoint of economic efficiency due to energy loss during heat treatment.
　本発明の目的は、上述した問題点に鑑み、ケイ酸植物由来のバイオマスを原料として、効率的にエネルギー回収するとともに純度の高い高品質なシリカを得ることができる非晶質シリカの製造方法及び非晶質シリカの製造装置を提供する点にある。 In view of the above-mentioned problems, an object of the present invention is a method for producing amorphous silica, which can efficiently recover energy and obtain high-purity and high-quality silica using a biomass derived from a silicic acid plant as a raw material. The point is to provide an apparatus for producing amorphous silica.
　上述の目的を達成するため、本発明による非晶質シリカの製造方法の第一の特徴構成は、ケイ酸植物由来のバイオマスを原料とする非晶質シリカの製造方法であって、前記バイオマスを熱分解処理してガス化するガス化ステップと、前記ガス化ステップで生じたバイオマス残渣を焼成処理する焼成ステップと、を含む点にある。 In order to achieve the above object, the first characteristic configuration of the method for producing amorphous silica according to the present invention is a method for producing amorphous silica using biomass derived from a silicic acid plant as a raw material, and the biomass is used. The point is that it includes a gasification step of pyrolyzing and gasifying, and a firing step of firing the biomass residue generated in the gasification step.
　ガス化ステップによってケイ酸植物由来のバイオマスが熱分解されて燃料として回収され、残ったバイオマス残渣が焼成処理されることによってバイオマス残渣に残存していた炭素成分などの不純物が除去され、純度の高いシリカが得られる。 Biomass derived from silicic acid plants is thermally decomposed by the gasification step and recovered as fuel, and the remaining biomass residue is calcined to remove impurities such as carbon components remaining in the biomass residue, resulting in high purity. Silica is obtained.
　同第二の特徴構成は、上述の第一の特徴構成に加えて、前記ガス化ステップは、非晶質シリカが結晶化する相転移温度域より低い温度域でガス化するステップである点にある。 The second feature configuration is that, in addition to the first feature configuration described above, the gasification step is a step of gasifying in a temperature range lower than the phase transition temperature range in which the amorphous silica crystallizes. be.
　相転移温度域以下の温度域でガス化されるので、非晶質のシリカが結晶化することがない。また炭素成分自体が結晶化したりシリカに取り込まれたりするようなことがなく、後の焼成ステップで純度の高いシリカが得られるようになる。 Since it is gasified in the temperature range below the phase transition temperature range, amorphous silica does not crystallize. Further, the carbon component itself is not crystallized or incorporated into silica, and high-purity silica can be obtained in a later firing step.
　同第三の特徴構成は、上述の第二の特徴構成に加えて、前記ガス化ステップは、前記バイオマス残渣の滞留時間が所定時間以下になるように調整される点にある。 The third feature configuration is that, in addition to the second feature configuration described above, the gasification step is adjusted so that the residence time of the biomass residue is equal to or less than a predetermined time.
　バイオマス残渣の滞留時間が調整されることによってバイオマス残渣に含まれるシリカの結晶化の確率を低減し、炭素成分自体が結晶化してシリカに取り込まれる確率を低減することができる。その結果、後の焼成ステップで純度の高いシリカを得ることができるようになる。 By adjusting the residence time of the biomass residue, the probability of crystallization of silica contained in the biomass residue can be reduced, and the probability that the carbon component itself crystallizes and is incorporated into silica can be reduced. As a result, high-purity silica can be obtained in a later firing step.
　同第四の特徴構成は、上述の第二または第三の特徴構成に加えて、前記ガス化ステップで得られたガスから燃料を生成する燃料生成ステップを備えている点にある。 The fourth characteristic configuration is that, in addition to the above-mentioned second or third characteristic configuration, a fuel generation step of generating fuel from the gas obtained in the gasification step is provided.
　ガス化ステップで得られたガスを燃料生成ステップにより燃料に変換することにより、燃料としての用途を広げることができる。 By converting the gas obtained in the gasification step into fuel in the fuel generation step, the application as fuel can be expanded.
　同第五の特徴構成は、上述の第一から第四の何れかの特徴構成に加えて、前記焼成ステップの実行前に、前記ガス化ステップで生じたバイオマス残渣を粉砕処理する粉砕ステップを備えている点にある。 The fifth characteristic configuration includes, in addition to any of the first to fourth characteristic configurations described above, a pulverization step for pulverizing the biomass residue generated in the gasification step before the execution of the calcination step. There is a point.
　ガス化ステップで生じたバイオマス残渣を粉砕処理した後に焼成ステップを実行することにより、焼成による不純物の分離が効率的に行なえるとともに、粒径の揃ったシリカを得ることができる。 By executing the firing step after pulverizing the biomass residue generated in the gasification step, impurities can be efficiently separated by firing and silica having a uniform particle size can be obtained.
　同第六の特徴構成は、上述の第一から第五の何れかの特徴構成に加えて、前記焼成ステップは、前記バイオマス残渣を炭素の燃焼温度域で所定時間焼成する第１焼成ステップと、前記第１焼成ステップの後に前記相転移温度域より低い温度域で所定時間焼成する第２焼成ステップとを含む点にある。 The sixth characteristic configuration is, in addition to any of the first to fifth characteristic configurations described above, the firing step includes a first firing step in which the biomass residue is fired in a carbon combustion temperature range for a predetermined time. The point is that the first firing step is followed by a second firing step in which firing is performed in a temperature range lower than the phase transition temperature range for a predetermined time.
　炭素の燃焼温度域で所定時間焼成する第１焼成ステップにより、バイオマス残渣に含まれる炭素成分を効率的に燃焼させて炭素由来の黒色成分を除去することができ、相転移温度域より低い温度域で所定時間焼成する第２焼成ステップによりシリカの結晶化を招くことなく不純物を除去して純度を上げることができる。 By the first firing step of firing in a carbon combustion temperature range for a predetermined time, the carbon component contained in the biomass residue can be efficiently burned to remove the carbon-derived black component, and the temperature range is lower than the phase transition temperature range. By the second firing step of firing for a predetermined time, impurities can be removed and the purity can be increased without causing crystallization of silica.
　本発明による非晶質シリカの製造装置の第一の特徴構成は、上述した第一から第六の何れかの特徴構成を備えた非晶質シリカの製造方法に用いられる非晶質シリカの製造装置であって、ケイ酸植物を含むバイオマスを熱分解処理してガス化するガス化炉と、前記ガス化炉から排出された熱分解ガスとバイオマス残渣の混合物からバイオマス残渣を分離する分離機構と、前記分離機構で分離されたバイオマス残渣を焼成して非晶質シリカを得る焼成炉と、を備えている点にある。 The first characteristic configuration of the amorphous silica production apparatus according to the present invention is the production of amorphous silica used in the method for producing amorphous silica having any of the above-mentioned first to sixth characteristic configurations. An apparatus that provides a gasification furnace that thermally decomposes and gasifies biomass containing silicic acid plants, and a separation mechanism that separates the biomass residue from a mixture of the thermal decomposition gas discharged from the gasifier and the biomass residue. The point is that the biomass residue separated by the separation mechanism is calcined to obtain amorphous silica.
　ガス化炉でケイ酸植物を含むバイオマスが熱分解され、遠心分離機で熱分解ガスとバイオマス残渣が分離され、焼成炉でバイオマス残渣が焼成されてシリカが得られる。 Biomass containing silicic acid plants is thermally decomposed in a gasification furnace, the pyrolysis gas and biomass residue are separated by a centrifuge, and the biomass residue is calcined in a calcining furnace to obtain silica.
　同第二の特徴構成は、上述の第一の特徴構成に加えて、前記分離機構で分離されたバイオマス残渣を破砕する破砕機をさらに備えている点にある。 The second characteristic configuration is that, in addition to the first characteristic configuration described above, a crusher for crushing the biomass residue separated by the separation mechanism is further provided.
　遠心分離機で分離されたバイオマス残渣を破砕機で破砕して粒度調整することにより焼成炉でバイオマス残渣を効率的に焼成することができる。 By crushing the biomass residue separated by the centrifuge with a crusher and adjusting the particle size, the biomass residue can be fired efficiently in the firing furnace.
　同第三の特徴構成は、上述の第一または第二の特徴構成に加えて、前記ガス化炉の後段には、前記ガス化炉で生成され前記分離機構で前記バイオマス残渣が分離された熱分解ガスから燃料を生成する反応装置を備えている点にある。 In addition to the above-mentioned first or second characteristic configuration, the third characteristic configuration is the heat generated in the gasification furnace and the biomass residue separated by the separation mechanism in the subsequent stage of the gasification furnace. It is equipped with a reactor that produces fuel from decomposition gas.
　ガス化炉で得られた熱分解ガスから反応装置により燃料を生成することで、バイオマスが保有するエネルギーを効率的に再利用することができる。 By generating fuel from the pyrolysis gas obtained in the gasification furnace with a reactor, the energy possessed by the biomass can be efficiently reused.
　以上説明した通り、本発明によれば、ケイ酸植物由来のバイオマスを原料として、効率的にエネルギー回収するとともに純度の高い高品質なシリカを得ることができる非晶質シリカの製造方法及び非晶質シリカの製造装置を提供することができるようになった。 As described above, according to the present invention, a method for producing amorphous silica and amorphous silica capable of efficiently recovering energy and obtaining high-purity and high-quality silica using silicic acid plant-derived biomass as a raw material. It has become possible to provide equipment for producing quality silica.
図１は本発明による非晶質シリカの製造方法の一例を示す説明図である。FIG. 1 is an explanatory diagram showing an example of a method for producing amorphous silica according to the present invention. 図２はＢＴＬプラントを構成するカス化炉及びＦＴ合成反応器の説明図である。FIG. 2 is an explanatory diagram of a cascading furnace and an FT synthesis reactor constituting the BTL plant. 図３は非晶質シリカの製造装置の一例を示す説明図である。FIG. 3 is an explanatory diagram showing an example of an apparatus for producing amorphous silica. 図４は非晶質シリカの製造装置の他の例を示す説明図である。FIG. 4 is an explanatory diagram showing another example of the device for producing amorphous silica. 図５（ａ）は実験Ｎｏ．３のガス化灰の熱重量分析結果の説明図、図５（ｂ）は基本条件によるガス化灰の熱重量分析結果の説明図である。FIG. 5A shows Experiment No. 3 is an explanatory diagram of the thermogravimetric analysis result of the gasified ash, and FIG. 5B is an explanatory diagram of the thermogravimetric analysis result of the gasified ash under the basic conditions. 図６はバイオマス残渣に対する低温燃焼実験の結果説明図である。FIG. 6 is an explanatory diagram of the results of a low temperature combustion experiment on a biomass residue. 図７は白色灰の成分分析結果の説明図である。FIG. 7 is an explanatory diagram of the component analysis result of white ash.
　以下、本発明による非晶質シリカの製造方法及び非晶質シリカの製造装置の一例を説明する。
　図１には、本発明による非晶質シリカの製造方法の一態様が示されている。農家で生産された籾米がライスセンターに出荷され、あるいはカントリーエレベータに貯蔵され、籾摺りされた後の大量の籾殻がＢＴＬ（Biomass To Liquid）プラントに原料として搬入される。 Hereinafter, an example of the method for producing amorphous silica and the apparatus for producing amorphous silica according to the present invention will be described.
FIG. 1 shows one aspect of the method for producing amorphous silica according to the present invention. Rice produced by farmers is shipped to rice centers or stored in country elevators, and a large amount of rice husks after being hulled are brought into a BTL (Biomass To Liquid) plant as raw materials.
　ＢＴＬプラントにはガス化炉とＦＴ合成反応器が設けられ、ガス化炉で籾殻が分解された合成ガスがＦＴ合成反応器（「ＦＴ合成炉」ともいう。）に供給されてＦＴ合成されることによりバイオ燃料（軽油やジェット燃料など）の液体燃料が生成される。 The BTL plant is provided with a gasification furnace and an FT synthesis reactor, and the synthetic gas obtained by decomposing the paddy shell in the gasification furnace is supplied to the FT synthesis reactor (also referred to as “FT synthesis reactor”) for FT synthesis. This produces liquid fuel for biofuels (light oil, jet fuel, etc.).
　生成されたバイオ燃料は輸送用燃料や農作業用燃料に用いられ、ＢＴＬプラントで生じた廃熱は園芸施設や温泉などの保温用熱源に供される。また、ＦＴ合成反応器でＦＴ合成することにより得られたオフガスはガスエンジン発電機やボイラなどの熱源利用機器に供され、熱源利用機器による発電電力が施設内で利用される。 The generated biofuel is used as fuel for transportation and fuel for agricultural work, and the waste heat generated in the BTL plant is used as a heat source for heat retention such as horticultural facilities and hot springs. Further, the off-gas obtained by FT synthesis with the FT synthesis reactor is used for heat source utilization equipment such as a gas engine generator and a boiler, and the power generated by the heat source utilization equipment is used in the facility.
　ガス化炉で熱分解された籾殻の残渣に含まれる大量のシリカ成分の一部は圃場に肥料として供され、残りは吸着剤などの原料として工業的に利用される。 A part of the large amount of silica component contained in the residue of rice husks pyrolyzed in the gasification furnace is used as fertilizer in the field, and the rest is industrially used as a raw material such as an adsorbent.
　図２には、ＢＴＬプラント１００の基本構成が示されている。
　当該ＢＴＬプラント１００は、バイオマスから液体燃料の原料となる合成ガスを生成するガス化炉１０と、生成された合成ガスから灰分等の固形物、硫化水素ガスや塩化水素ガス、アンモニア等を除去するサイクロン、スクラバー、活性炭吸着塔などを備えたガス精製装置２０と、ガス精製装置２０を経て精製された合成ガスから燃料を合成するＦＴ合成反応器３０を備えている。 FIG. 2 shows the basic configuration of the BTL plant 100.
The BTL plant 100 removes solids such as ash, hydrogen sulfide gas, hydrogen chloride gas, ammonia and the like from the gasification furnace 10 that generates synthetic gas that is a raw material for liquid fuel from biomass and the generated synthetic gas. It includes a gas purification device 20 equipped with a cyclone, a scrubber, an activated charcoal adsorption tower, and the like, and an FT synthesis reactor 30 that synthesizes fuel from synthetic gas purified through the gas purification device 20.
　ガス化炉１０は、炉温が５００℃以上１０００℃以下の高温下で、バイオマスを水蒸気或いは過熱水蒸気で還元加熱して合成ガス（Ｈ２、ＣＯ）を生成する反応塔を備えている。 Gasifier 10, the furnace temperature is at a high temperature of 500 ° C. or higher 1000 ° C. or less, and a reaction tower biomass and reduced heating with steam or superheated steam to produce a synthesis gas (H 2, CO).
　例えば高周波加熱などにより常圧で約５００℃程度に加熱された水蒸気とバイオマスとが反応塔の内部で水性ガス反応や、水性ガスシフト反応して、反応塔上部の排気口から排気され、排気管を経てガス精製装置２０に導かれる。水性ガス反応は主に反応塔の下部で生じ、水性ガスシフト反応は主に反応塔を上昇する過程で生じる。ガス精製装置２０には誘引送風機が設けられ、反応塔内部が負圧に維持され、反応塔内で生成されたガスがガス精製装置２０に誘引されて精製される。 For example, steam and biomass heated to about 500 ° C. at normal pressure by high-frequency heating or the like undergo a water-gas reaction or a water-gas shift reaction inside the reaction tower, and are exhausted from the exhaust port at the top of the reaction tower to open the exhaust pipe. Then, it is guided to the gas purification device 20. The water gas reaction occurs mainly in the lower part of the reaction column, and the water gas shift reaction occurs mainly in the process of ascending the reaction column. The gas purification device 20 is provided with an attracting blower, the inside of the reaction tower is maintained at a negative pressure, and the gas generated in the reaction tower is attracted to the gas purification device 20 for purification.
　バイオマス供給装置は一端が反応塔の下方にフランジ接続された筒状のケーシングと筒状のケーシングに収容されたスクリュー羽根とを備えたスクリューコンベア機構で構成され、他端側に定量供給機構を備えたホッパーが設けられている。数ｍｍ程度に破砕された籾殻などの乾燥系のバイオマスがホッパーに充填され、スクリュー羽根で圧密に搬送されて反応塔に投入される。バイオマス供給装置の下方に設けられた水蒸気供給部のノズル先端から供給される水蒸気によって反応塔の内部でバイオマスが流動する噴流床が形成される。 The biomass supply device is composed of a screw conveyor mechanism having a tubular casing whose one end is flanged below the reaction tower and screw blades housed in the tubular casing, and a fixed quantity supply mechanism on the other end side. There is a hopper. Dry biomass such as rice husks crushed to about several mm is filled in the hopper, consolidated by screw blades, and put into the reaction tower. A jet bed in which biomass flows is formed inside the reaction tower by steam supplied from the tip of a nozzle of a steam supply unit provided below the biomass supply device.
　噴流床が形成される領域が主に水性ガス反応が行なわれる第１領域Ｒ１となる。更に第１領域Ｒ１の上方に主に水性ガスシフト反応が行なわれる第２領域Ｒ２が形成される。 The region where the jet bed is formed is the first region R1 where the water gas reaction is mainly performed. Further, a second region R2 in which the water-gas shift reaction is mainly performed is formed above the first region R1.
　水性ガス反応とは、次式に示すように、５００℃以上の高温環境下でバイオマスである固体炭素Ｃと水蒸気Ｈ２Ｏとから一酸化炭素ＣＯと水素Ｈ２が生成される吸熱反応をいう。水蒸気供給部に加えて少量の酸素ガスまたは空気を反応塔に供給する酸素供給部が設けられ、バイオマスの一部の燃焼により必要な反応熱が与えられる。
Ｃ＋Ｈ２Ｏ　→　ＣＯ＋Ｈ２ As shown in the following equation, the water gas reaction is an endothermic reaction in which carbon monoxide CO and hydrogen H 2 are produced from solid carbon C and water vapor H 2 O, which are biomass, in a high temperature environment of 500 ° C. or higher. .. In addition to the steam supply unit, an oxygen supply unit that supplies a small amount of oxygen gas or air to the reaction tower is provided, and the required reaction heat is given by burning a part of the biomass.
C + H 2 O → CO + H 2
　水性ガスシフト反応とは、次式に示すように、通常は８００℃前後の高温環境下で一酸化炭素ＣＯと水蒸気Ｈ２Ｏとから二酸化炭素ＣＯ２と水素Ｈ２が生成される発熱反応をいう。
ＣＯ＋Ｈ２Ｏ　→　ＣＯ２＋Ｈ２ As shown in the following equation, the water-gas shift reaction is an exothermic reaction in which carbon dioxide CO 2 and hydrogen H 2 are produced from carbon monoxide CO and water vapor H 2 O in a high temperature environment of about 800 ° C. ..
CO + H 2 O → CO 2 + H 2
　第１領域Ｒ１でバイオマスから生成された合成ガス及びチャーや灰はそのガス流れ方向下流側の第２領域Ｒ２に上昇して上述した水性ガスシフト反応が促進される。なお、水性ガスシフト反応に必要な水蒸気は水蒸気供給部から供給され、第１領域Ｒ１で水性ガス反応に寄与しなかった水蒸気が消費される。 Syngas and char and ash generated from biomass in the first region R1 rise to the second region R2 on the downstream side in the gas flow direction, and the above-mentioned water-gas shift reaction is promoted. The water vapor required for the water-gas shift reaction is supplied from the water vapor supply unit, and the water vapor that did not contribute to the water-gas reaction is consumed in the first region R1.
　反応塔で得られた合成ガスが後段のガス精製装置２０で精製され、不純物が除去された後にヒータ及び圧縮機を介して高温高圧に加熱及び加圧されてＦＴ合成反応器３０に投入され、ＦＴ合成される。 The synthetic gas obtained in the reaction tower is purified by the gas purification apparatus 20 in the subsequent stage, and after impurities are removed, it is heated and pressurized to a high temperature and high pressure via a heater and a compressor, and charged into the FT synthesis reactor 30. FT is synthesized.
　ＦＴ合成とは、Ｆｉｓｃｈｅｒ－Ｔｒｏｐｓｃｈ合成の略で、「ＦＴ法」や「ＦＴ反応」とも呼ばれ、一酸化炭素と水素から触媒反応を用いて液体炭化水素を合成する一連の合成反応プロセスを指す。 FT synthesis is an abbreviation for Fischer-Tropsch synthesis, also called "FT method" or "FT reaction", and refers to a series of synthetic reaction processes that synthesize liquid hydrocarbons from carbon monoxide and hydrogen using a catalytic reaction. ..
　ＦＴ合成反応器３０に投入された合成ガスは、触媒が分散された溶媒中に投入されて所望の炭化水素に合成される。触媒の種類や性状により変化するが、例えば、メタノールを合成する場合には、水素と一酸化炭素の比率Ｈ２／ＣＯは約２であることが好ましい。また本実施形態で軽油を合成する場合には水素と一酸化炭素の比率Ｈ２／ＣＯは約１であることが好ましい。 The syngas charged into the FT synthesis reactor 30 is charged into a solvent in which a catalyst is dispersed and synthesized into a desired hydrocarbon. Although it varies depending on the type and properties of the catalyst, for example, when synthesizing methanol, the ratio H 2 / CO of hydrogen to carbon monoxide is preferably about 2. Further, when synthesizing light oil in the present embodiment, the ratio H 2 / CO of hydrogen to carbon monoxide is preferably about 1.
　つまり、ＦＴ合成で所望の炭化水素を効率的に得るために、水素と一酸化炭素の比率Ｈ２／ＣＯが調整されている必要があり、この比率は同じ種類の炭化水素を得る場合でもＦＴ合成で使用される触媒の種類にも依存する。 That is, in order to efficiently obtain the desired hydrocarbon in FT synthesis, the ratio H 2 / CO of hydrogen and carbon monoxide needs to be adjusted, and this ratio is FT even when the same type of hydrocarbon is obtained. It also depends on the type of catalyst used in the synthesis.
　ガス化炉で籾殻が熱分解される際の温度は、少なくとも籾殻に含まれるシリカが結晶化する相転移温度域よりも低い温度域である必要があり、シリカが結晶化すると健康への影響の観点からも工業的利用に不向きとなる。また非晶質シリカであっても純度が低く炭素成分が含まれていると黒く着色した状態となるので、ファンデーションなどの化粧品、食品添加剤、医薬品添加剤、樹脂添加剤、塗料添加剤、ゴム充填剤などの材料には使用できず、用途が制限される。 The temperature at which the rice husks are thermally decomposed in the gasification furnace must be at least a temperature range lower than the phase transition temperature range in which the silica contained in the rice husks crystallizes, and the crystallization of silica has an effect on health. From the viewpoint, it is not suitable for industrial use. Even if it is amorphous silica, if it has low purity and contains carbon components, it will be colored black, so cosmetics such as foundations, food additives, pharmaceutical additives, resin additives, paint additives, rubber. It cannot be used for materials such as fillers, and its use is limited.
　本発明による非晶質シリカの製造方法によれば、籾殻からエネルギーを再生しながらも、純度の高い非晶質シリカを効率的に得ることができる。なお、農業廃棄物の一つである籾殻は約７０％がセルロース、ヘミセルロース、リグニン等の炭水化物であり、約１５～２０％がシリカであり、残部の大半が水分でアルカリ不純物を僅かに含んでいる。このようなシリカを含むバイオマスを資源として再生する場合に本発明が好適に用いられる。従って、本発明の適用対象は籾殻に限るものではなく、稲わら、麦わら、竹、トウモロコシ、サトウキビ、薄、トクサなどケイ酸植物由来のバイオマスとなる。 According to the method for producing amorphous silica according to the present invention, high-purity amorphous silica can be efficiently obtained while regenerating energy from rice husks. Rice husks, which are one of the agricultural wastes, are about 70% carbohydrates such as cellulose, hemicellulose, and lignin, about 15 to 20% silica, and most of the rest is water and contains a small amount of alkaline impurities. There is. The present invention is preferably used when such biomass containing silica is regenerated as a resource. Therefore, the application of the present invention is not limited to rice husks, but biomass derived from silicic acid plants such as rice straw, straw, bamboo, corn, sugar cane, thin, and horsetail.
　以下、非晶質シリカの製造方法について詳述する。
　ケイ酸植物由来のバイオマスを原料とする非晶質シリカの製造方法は、バイオマスをガス化炉で熱分解処理するガス化ステップと、ガス化ステップで生じたバイオマス残渣を焼成炉で焼成処理する焼成ステップと、を含む。ガス化ステップによってケイ酸植物由来のバイオマスが水素と一酸化炭素に熱分解されて燃料として回収され、残ったバイオマス残渣が焼成処理されることによってバイオマス残渣に残存していた炭素成分などの不純物が除去され、純度の高いシリカが得られる。 Hereinafter, the method for producing amorphous silica will be described in detail.
A method for producing amorphous silica using biomass derived from a siliceous plant as a raw material is a gasification step in which biomass is thermally decomposed in a gasification furnace and a firing process in which the biomass residue generated in the gasification step is fired in a firing furnace. Including steps. By the gasification step, the biomass derived from the silicic acid plant is thermally decomposed into hydrogen and carbon monoxide and recovered as fuel, and the remaining biomass residue is calcined to remove impurities such as carbon components remaining in the biomass residue. It is removed to give high purity silica.
　上述したように、バイオマスに水蒸気を供給して水性ガス反応及び水性ガスシフト反応を生起させ、水素ガスや一酸化炭素ガスのような合成ガスを生成するプロセスを採用するものでは、バイオマス残渣に含まれるシリカが結晶化する相転移温度域よりも低い温度域、例えば８００℃以下の温度域で、水性ガスシフト反応させることが好ましい。相転移温度域以下の温度域で水性ガスシフト反応が行なわれるので、非晶質のシリカが結晶化することがない。また炭素成分自体が結晶化したりシリカに取り込まれたりするようなことがなく、後の焼成ステップで炭素成分が効果的に除去されて純度の高いシリカが得られるようになる。 As described above, those adopting a process of supplying water vapor to biomass to cause a water gas reaction and a water gas shift reaction to generate a synthetic gas such as hydrogen gas or carbon monoxide gas are included in the biomass residue. It is preferable to carry out the water-gas shift reaction in a temperature range lower than the phase transition temperature range in which silica crystallizes, for example, a temperature range of 800 ° C. or lower. Since the water-gas shift reaction is carried out in a temperature range below the phase transition temperature range, amorphous silica does not crystallize. Further, the carbon component itself is not crystallized or incorporated into silica, and the carbon component is effectively removed in the subsequent firing step to obtain highly pure silica.
　ガス化ステップは、バイオマス残渣の流動時間、つまり反応塔に投入されたバイオマスが水性ガス反応により灰化したバイオマス残渣がガス精製装置２０に向けて反応塔から流出するまでの時間が所定時間以下になるように水蒸気の供給量または水蒸気への酸素ガスの混合量が調整されることが好ましい。 In the gasification step, the flow time of the biomass residue, that is, the time until the biomass residue in which the biomass charged into the reaction tower is incinerated by the water gas reaction flows out from the reaction tower toward the gas purification apparatus 20 is set to a predetermined time or less. It is preferable that the amount of water vapor supplied or the amount of oxygen gas mixed with water vapor is adjusted so as to be.
　バイオマスが水蒸気によって流動しながら水性ガス反応により熱分解され、さらに水性ガスシフト反応が生起されてバイオマス残渣が残る。その際の水蒸気の供給量または水蒸気への酸素ガスの混合量を調整することにより、バイオマス残渣の滞留時間が調整される。その結果、バイオマス残渣に含まれるシリカの結晶化の確率を低減し、炭素成分自体が結晶化してシリカに取り込まれる確率を低減することができる。このような調整により後の焼成ステップで純度の高いシリカを得ることができるようになる。 Biomass is thermally decomposed by water gas reaction while flowing by water vapor, and further water gas shift reaction occurs and biomass residue remains. By adjusting the amount of water vapor supplied or the amount of oxygen gas mixed with the water vapor at that time, the residence time of the biomass residue is adjusted. As a result, the probability of crystallization of silica contained in the biomass residue can be reduced, and the probability that the carbon component itself is crystallized and incorporated into silica can be reduced. Such adjustment makes it possible to obtain high-purity silica in a later firing step.
　外部エネルギーを消費することなく水蒸気を生成するという観点で、ガス化ステップで得られた熱分解ガスの保有熱を利用して熱交換することにより水蒸気を加熱する水蒸気過熱ステップを備えていることが好ましく経済性を高めることができる。 From the viewpoint of generating steam without consuming external energy, it is possible to have a steam superheating step that heats steam by exchanging heat using the heat possessed by the thermal decomposition gas obtained in the gasification step. It is possible to preferably increase the economic efficiency.
　また、ガス化ステップで得られたガスを原料にＦＴ合成処理してバイオ燃料を生成するバイオ燃料生成ステップを備えていることが好ましく、エネルギーの効率的利用の観点で燃料としての用途を広げることができる。 In addition, it is preferable to have a biofuel generation step in which the gas obtained in the gasification step is used as a raw material for FT synthesis processing to generate biofuel, and the application as a fuel is expanded from the viewpoint of efficient use of energy. Can be done.
　焼成ステップの実行前に、ガス化ステップで生じたバイオマス残渣を粉砕処理する粉砕ステップを備えていることが好ましく、焼成による不純物の分離が効率的に行なえるとともに、粒径の揃ったシリカを得ることができ、これにより焼成ステップにおける白色化の促進と均質化を実現できる。 Prior to the execution of the calcination step, it is preferable to include a pulverization step for pulverizing the biomass residue generated in the gasification step, so that impurities can be efficiently separated by calcination and silica having a uniform particle size can be obtained. This allows for the promotion and homogenization of whitening in the firing step.
　焼成ステップでは、バイオマス残渣を炭素の燃焼温度域で所定時間焼成する第１焼成ステップと、第１焼成ステップの後に第１焼成温度より高い温度であり、相転移温度域より低い温度域で所定時間焼成する第２焼成ステップとを含むことが好ましい。 In the firing step, a first firing step in which the biomass residue is fired in a carbon combustion temperature range for a predetermined time, and a temperature higher than the first firing temperature after the first firing step, and a temperature range lower than the phase transition temperature range for a predetermined time. It is preferable to include a second firing step for firing.
　炭素の燃焼温度域、具体的には４００～６００℃の温度域で所定時間焼成する第１焼成ステップにより、バイオマス残渣に含まれる炭素成分を効率的に燃焼させて炭素由来の黒色成分を除去することができ、相転移温度域以下の温度域、具体的には８００℃以下の温度域で所定時間焼成する第２焼成ステップによりシリカの結晶化を招くことなく不純物を除去して純度を上げることができる。 The carbon component contained in the biomass residue is efficiently burned to remove the black component derived from carbon by the first firing step of firing in a carbon combustion temperature range, specifically, a temperature range of 400 to 600 ° C. for a predetermined time. It is possible to remove impurities and increase the purity by the second firing step of firing for a predetermined time in a temperature range below the phase transition temperature range, specifically, a temperature range below 800 ° C. without causing crystallization of silica. Can be done.
　なお、ガス化ステップでは水性ガス反応以外に、低酸素濃度雰囲気化でバイオマスを加熱して乾留処理するような熱分解プロセスを採用するものであってもよい。 In addition to the water gas reaction, the gasification step may employ a pyrolysis process in which the biomass is heated and carbonized in a low oxygen concentration atmosphere.
　図３には、上述した非晶質シリカの製造方法を使用するための晶質シリカの製造装置の一例が示されている。
　当該非晶質シリカの製造装置は、ケイ酸植物を含むバイオマスを熱分解処理してガス化するガス化炉と、ガス化炉から排出された熱分解ガスとバイオマス残渣の混合物からバイオマス残渣を分離する分離機構、例えば遠心分離機サイクロンフィルターなどと、分離機構で分離されたバイオマス残渣を破砕する破砕機と、破砕されたバイオマス残渣を焼成して非晶質シリカを得る焼成炉とを備えている。焼成炉として電気焼成炉やガス焼成炉などを適宜用いることができる。 FIG. 3 shows an example of an apparatus for producing crystalline silica for using the above-mentioned method for producing amorphous silica.
The amorphous silica production apparatus separates the biomass residue from a gasification furnace that pyrolyzes and gasifies biomass containing silicic acid plants and a mixture of the pyrolysis gas and biomass residue discharged from the gasification furnace. It is equipped with a separation mechanism such as a centrifuge cyclone filter, a crusher for crushing the biomass residue separated by the separation mechanism, and a firing furnace for calcining the crushed biomass residue to obtain amorphous silica. .. As the firing furnace, an electric firing furnace, a gas firing furnace, or the like can be appropriately used.
　ガス化炉はバイオマスを水蒸気により流動させて水性ガス反応及び水性ガスシフト反応させる噴流床炉で構成され、噴流床炉から排出された熱分解ガスとバイオガス残渣の混合物から分離機構でバイオマス残渣が分離された熱分解ガスから燃料を生成する反応装置をさらに備えている。 The gasification furnace is composed of a jet bed furnace in which biomass is flowed by steam to cause a water gas reaction and a water gas shift reaction, and the biomass residue is separated from a mixture of pyrolysis gas and biogas residue discharged from the jet bed furnace by a separation mechanism. It is further equipped with a reactor that produces fuel from the produced pyrolysis gas.
　灯油などの化石燃料またはバイオマスを用いたボイラにより生成された過熱水蒸気、及び、酸素発生装置ＰＳＡ（Pressure Swing Adsorption）で生成された酸素ガスが、バイオマスとともにガス化炉に投入され、ガス化炉で生じる水性ガス反応及び水性ガスシフト反応によって生成された合成ガスに含まれるバイオマス残渣がサイクロンによって分離され、破砕機で所定の粒径に破砕された後に焼成炉に投入され、焼成されることにより高純度の非晶質シリカが得られる。 Superheated steam generated by a boiler using fossil fuels such as kerosene or biomass, and oxygen gas generated by the oxygen generator PSA (Pressure Swing Adsorption) are put into the gasification furnace together with the biomass, and in the gasification furnace. Biomass residue contained in the generated water gas reaction and water gas shift reaction is separated by a cyclone, crushed to a predetermined particle size by a crusher, charged into a firing furnace, and fired to obtain high purity. Amorphous silica can be obtained.
　サイクロンでバイオマス残渣が除去された合成ガスが空気予熱用の熱交換器に導かれ、その後にスクラバーで洗浄されてアンモニアガスや塩化水素ガスなどが除去される。ガス精製部で精製された合成ガスからＣＯ２吸着塔でＣＯ２が除去され、昇温昇圧器で昇温昇圧された合成ガスがＦＴ合成反応器に投入される。ＦＴ反応によって油が合成されガス成分として気化したものが凝縮器で液化されて燃料としての液体燃料が得られる。凝縮器を通過した低級炭化水素ガスはオフガスとしてガス発電機の燃料に供される。 The synthetic gas from which the biomass residue has been removed by the cyclone is led to a heat exchanger for air preheating, and then washed with a scrubber to remove ammonia gas, hydrogen chloride gas, and the like. CO 2 is removed from the synthetic gas purified by the gas purification unit in the CO 2 adsorption tower, and the synthetic gas whose temperature has been raised and raised by the temperature riser and booster is charged into the FT synthesis reactor. Oil is synthesized by the FT reaction and vaporized as a gas component, which is liquefied in a condenser to obtain a liquid fuel as a fuel. The lower hydrocarbon gas that has passed through the condenser is used as off-gas for fuel of the gas generator.
　図４には、上述した非晶質シリカの製造方法を使用するための晶質シリカの製造装置の他の例が示されている。バイオマスを原料としてガス化炉でガス化し、サイクロンで分離されたバイオマス残渣を破砕機で破砕し、焼成炉で焼成することにより非晶質シリカを生成する構成は図３と同一である。サイクロンを通過した合成ガスをＦＴ合成することなく、ガス発電機の燃料として用いられる点が図３と相違する。 FIG. 4 shows another example of a crystalline silica manufacturing apparatus for using the above-mentioned amorphous silica manufacturing method. The configuration of producing amorphous silica by gasifying biomass as a raw material in a gasification furnace, crushing the biomass residue separated by a cyclone with a crusher, and firing in a firing furnace is the same as in FIG. It differs from FIG. 3 in that the synthetic gas that has passed through the cyclone is used as a fuel for a gas generator without FT synthesis.
　上述した非晶質シリカの製造方法を適用して、籾殻から化粧品原料（ファンデーション原料）として使用可能なシリカの製造条件の策定実験を行なった。
　化粧品原料としてシリカに求められる品質は、非晶質であること、粒径が１０μｍ程度であること、シリカ純度が９７％以上であること、の三点となる。シリカ純度が９７％以上であれば、白色を呈し有害物質を含まないと評価できる。 By applying the above-mentioned method for producing amorphous silica, an experiment was conducted to formulate conditions for producing silica that can be used as a raw material for cosmetics (foundation raw material) from rice husks.
The qualities required for silica as a raw material for cosmetics are amorphous, a particle size of about 10 μm, and a silica purity of 97% or more. If the silica purity is 97% or more, it can be evaluated that it is white and does not contain harmful substances.
　ガス化炉の運転条件として、主に水性ガスシフト反応が行なわれる第２領域Ｒ２（図２参照）の温度であるガス化炉の上部温度（運転条件１）、水蒸気／炭素の比（運転条件２）、空気／純酸素置換率（運転条件３）、処理量（運転条件４）を、基本条件に対して変化させた場合に、ガス化率、バイオマス残渣の組成、粒度がどのようになるかを試験した。 The operating conditions of the gasifier are the upper temperature of the gasifier (operating condition 1), which is the temperature of the second region R2 (see FIG. 2) where the water-gas shift reaction is mainly performed, and the steam / carbon ratio (operating condition 2). ), Air / pure oxygen substitution rate (operating condition 3), and processing amount (operating condition 4), what will be the gasification rate, biomass residue composition, and particle size when changed with respect to the basic conditions? Was tested.
　基本条件とは、バイオマスを用いてＦＴ合成する場合に最大効率でバイオ燃料を得ることができる条件であり、ガス化炉の上部温度が９５０℃、水蒸気／炭素の比が１．７、空気／純酸素置換率が０％（純酸素１００％）、処理量１ｔ／日に設定されている。なお、第１領域Ｒ１の温度は約５００～６００℃に設定されている。 The basic conditions are the conditions under which biofuel can be obtained with maximum efficiency when FT synthesis is performed using biomass, the upper temperature of the gasifier is 950 ° C, the steam / carbon ratio is 1.7, and air / carbon. The pure oxygen substitution rate is set to 0% (pure oxygen 100%), and the processing amount is set to 1 t / day. The temperature of the first region R1 is set to about 500 to 600 ° C.
　様々な運転条件で試験した結果、運転条件１を８００℃（基本条件９５０℃）、運転条件２を１．７（基本条件１．７）、運転条件３を１００％（基本条件０％）、運転条件４を１ｔ／ｄ（基本条件１ｔ／ｄ）に設定した特定運転条件でのバイオマス残渣に対して、８００℃で焼成した場合に灰が白色化（具体的には薄桃色）しており、６００℃及び５５０℃で焼成した場合に灰がほぼ白色（具体的には極薄灰色）となることが判明し、他の運転条件による試験結果では、同様の焼成条件でも灰色または黒灰色の灰しか得られなかった。 As a result of testing under various operating conditions, operating condition 1 was 800 ° C. (basic condition 950 ° C.), operating condition 2 was 1.7 (basic condition 1.7), and operating condition 3 was 100% (basic condition 0%). When the biomass residue under the specific operating condition in which the operating condition 4 is set to 1 t / d (basic condition 1 t / d) is fired at 800 ° C., the ash becomes white (specifically, light pink). , 600 ° C and 550 ° C, it was found that the ash became almost white (specifically, ultra-light gray), and the test results under other operating conditions showed that the ash was gray or black-gray even under the same firing conditions. Only ash was obtained.
　図５（ａ），（ｂ）には熱重量分析結果が示されている。図５（ｂ）に示すように、基本条件でガス化処理したバイオマス残渣を加熱（焼成）する場合には、炭素燃焼の発熱ピークが２つ（時間４１．５５ｍｉｎ．と４４．１３ｍｉｎ．）存在しているが、図５（ａ）に示すように、実験Ｎｏ．３では炭素燃焼の発熱ピークが１つ（時間４２．８３ｍｉｎ．）になることが判明した。 The results of thermogravimetric analysis are shown in FIGS. 5 (a) and 5 (b). As shown in FIG. 5 (b), when the biomass residue gasified under the basic conditions is heated (calcined), there are two exothermic peaks of carbon combustion (time 41.55 min. And 44.13 min.). However, as shown in FIG. 5 (a), Experiment No. In No. 3, it was found that the exothermic peak of carbon combustion became one (time 42.83 min.).
　基本条件でのガス化処理では、９５０℃の高温でガス化される際に炭素成分の一部が結晶化して燃え難くなっているが、実験Ｎｏ．３では８００℃でガス化されるというマイルドな条件の下で、炭素がソフトカーボン即ち官能基が多い燃えやすい炭素のみになったことにより炭素がほぼ完全に燃焼し、白色化したと考えられる。 In the gasification treatment under the basic conditions, when gasified at a high temperature of 950 ° C, a part of the carbon component crystallized and became hard to burn. In No. 3, it is considered that the carbon was almost completely burned and whitened because the carbon became only soft carbon, that is, flammable carbon having many functional groups under the mild condition of gasification at 800 ° C.
　ＳＥＭ画像で観察したところ、燃焼実験後の灰はシリカ主体でやや扁平な形状であったが、溶融はしておらず、もみ殻由来の複雑な構造は維持したままであった。しかし、８００℃×３時間燃焼後のシリカは、微量ではあるが結晶質のシリカ（クリストバライト０．６％、石英０．３％）が同定された。 When observed by SEM images, the ash after the combustion experiment was mainly silica and had a slightly flat shape, but it was not melted and the complicated structure derived from rice husks was maintained. However, as the silica after burning at 800 ° C. for 3 hours, crystalline silica (cristobalite 0.6%, quartz 0.3%) was identified although it was a trace amount.
　次に、基本条件（ガス化炉の上部温度が９５０℃）でガス化処理したバイオマス残渣（試料Ｎｏ．１，２，３）及び、特定運転条件（ガス化炉の上部温度が８００℃）でガス化処理したバイオマス残渣（試料Ｎｏ．１～１０）を、粉砕処理した後に、電気マッフル炉（空気雰囲気）を用いて以下の各種条件で加熱して炭素を燃焼し、粒子の外観（炭素の除去状況）を観察した。 Next, under the basic conditions (upper temperature of the gasification furnace is 950 ° C.) and the biomass residue (Sample Nos. 1, 2, 3) gasified under the specific operating conditions (upper temperature of the gasification furnace is 800 ° C.). After the gasified biomass residue (Samples Nos. 1 to 10) is crushed, it is heated in an electric muffle furnace (air atmosphere) under the following conditions to burn carbon, and the appearance of particles (carbon The removal status) was observed.
　燃焼の昇温速度を、急速（設定温度の炉内に投入）と低速（炉内に入れて２００℃/時間で昇温）の２種類とし、燃焼温度を６００～８００℃［８００℃以上は結晶化する］の間の温度とし、燃焼時間を１～５時間の１時間単位で異ならせた時間とした。 There are two types of combustion temperature rise rates: rapid (put in the furnace at the set temperature) and low speed (heat up at 200 ° C / hour in the furnace), and the combustion temperature is 600 to 800 ° C [800 ° C or higher. The temperature was set to between [Crystalize], and the burning time was set to a different time in 1-hour units of 1 to 5 hours.
　図６に実験結果が示されている。
　基本条件（ガス化炉の上部温度が９５０℃）でガス化処理したバイオマス残渣の灰については、昇温速度、燃焼温度、燃焼時間を変えても白色化しなかった。 The experimental results are shown in FIG.
The ash of the biomass residue gasified under the basic conditions (the upper temperature of the gasification furnace was 950 ° C.) was not whitened even when the heating rate, the combustion temperature, and the combustion time were changed.
　特定運転条件（ガス化炉の上部温度が、シリカが結晶化する相転移温度域以下の温度域である８００℃）でガス化処理したバイオマス残渣（試料Ｎｏ．１～１０）の灰は白色化しやすくなった。ガス化温度の低下により、シリカが結晶化することなく、また炭素が炭化せず燃えやすいソフトカーボンになったためと考えられる。 The ash of the biomass residue (Samples Nos. 1 to 10) gasified under specific operating conditions (the upper temperature of the gasification furnace is 800 ° C., which is below the phase transition temperature range at which silica crystallizes) is whitened. It's easier. It is probable that due to the decrease in gasification temperature, silica did not crystallize and carbon did not carbonize and became flammable soft carbon.
　さらに、試料Ｎｏ．２，３，６，８の結果に示すように、燃焼の昇温速度を低速にすることで白色化しやすくなり、８００℃で２時間以上、７５０℃で４時間、７００℃で５時間の燃焼を行うことで、ガス化灰を白色化することが確認できた。 Furthermore, sample No. As shown in the results of 2, 3, 6 and 8, it becomes easier to whiten by lowering the temperature rise rate of combustion, and combustion at 800 ° C. for 2 hours or more, 750 ° C. for 4 hours, and 700 ° C. for 5 hours. It was confirmed that the gasified ash was whitened by performing the above.
　試料Ｎｏ．１，４，５，７，９，１０の結果に示すように、急速に昇温すると白色化が困難であることが確認された。シリカの一部が溶けて炭素をコーティングし、燃えにくくなるためと考えられる。 Sample No. As shown in the results of 1, 4, 5, 7, 9 and 10, it was confirmed that whitening was difficult when the temperature was raised rapidly. It is thought that this is because a part of silica melts and coats carbon, making it difficult to burn.
　図７には、試料Ｎｏ．６の白色灰に対する成分分析結果が示されている。低温燃焼により白色灰の炭素（Ｃ）濃度は０．１％以下となり、シリカ（ＳｉＯ２）が高純度化して９７％以上となっていた。
　また、シリカ以外の成分として、カリウム（Ｋ）、ナトリウム（Ｎａ）、カルシウム（Ｃａ）、鉄（Ｆｅ）、リン（Ｐ）などが微量に含まれていた。 In FIG. 7, the sample No. The component analysis result for the white ash of No. 6 is shown. Due to low temperature combustion, the carbon (C) concentration of the white ash became 0.1% or less, and the silica (SiO 2 ) was highly purified to 97% or more.
Further, as components other than silica, potassium (K), sodium (Na), calcium (Ca), iron (Fe), phosphorus (P) and the like were contained in a trace amount.
　しかし、有害元素として規制されている鉛（Ｐｂ）、ヒ素（Ａｓ）濃度は規準値以下であることが確認された。また、シリカ結晶である石英、クリストバライト、トリジマイトは定量下限未満であり、シリカは低温燃焼後も非結晶であった。なお、粒度分布は事前粉砕の条件（粉砕量、粉砕媒体の種類と数、粉砕時間）を調整することで１０μｍ前後に粉砕できることが確認された。 However, it was confirmed that the concentrations of lead (Pb) and arsenic (As), which are regulated as harmful elements, are below the standard values. Further, the silica crystals such as quartz, cristobalite and tridimite were below the lower limit of quantification, and silica was amorphous even after low temperature combustion. It was confirmed that the particle size distribution can be crushed to around 10 μm by adjusting the conditions for pre-crushing (crushing amount, type and number of crushing medium, crushing time).
　以上の実験の結果、バイオマスを水蒸気により流動させて水性ガス反応及び水性ガスシフト反応させるガス化ステップでは、バイオマス残渣に含まれるシリカが結晶化する相転移温度域以下の温度域で、水性ガスシフト反応させることが好ましいこと、ガス化ステップでは、バイオマス残渣の流動時間が所定時間以下になるように水蒸気の供給量または水蒸気への酸素ガスの混合量が調整されることが好ましいことが裏付けられた。 As a result of the above experiments, in the gasification step in which the biomass is fluidized by water vapor to cause a water-gas reaction and a water-gas shift reaction, the water-gas shift reaction is carried out in a temperature range below the phase transition temperature range in which silica contained in the biomass residue crystallizes. It was confirmed that it is preferable that the amount of water vapor supplied or the amount of oxygen gas mixed with the water vapor is adjusted so that the flow time of the biomass residue is less than a predetermined time in the gasification step.
　なお、焼成ステップの実行前に、ガス化ステップで生じたバイオマス残渣を５～１５μｍ程度に粉砕処理する粉砕ステップを備えていることが好ましく、焼成ステップでは、バイオマス残渣を炭素の燃焼温度域で所定時間焼成する第１焼成ステップと、第１焼成ステップの後に相転移温度域以下の温度域で所定時間焼成する第２焼成ステップとを含むことが好ましい。 Before the firing step is executed, it is preferable to include a crushing step of crushing the biomass residue generated in the gasification step to about 5 to 15 μm. In the firing step, the biomass residue is predetermined in the carbon combustion temperature range. It is preferable to include a first firing step of firing for a time and a second firing step of firing for a predetermined time in a temperature range equal to or lower than the phase transition temperature range after the first firing step.
　炭素の燃焼温度域である４００～６００℃の温度域に向けて、１００～２００℃／時間でゆっくり昇温し、４００～６００℃で２～３時間保持することにより、バイオマス残渣に含まれる炭素成分を効率的に燃焼させて炭素由来の黒色成分を除去することができ、その後７００～８００℃の高温で１～３時間加熱することにより、シリカの結晶化を招くことなく不純物を除去して純度を上げることができる。 Carbon contained in the biomass residue by slowly raising the temperature at 100 to 200 ° C./hour toward the temperature range of 400 to 600 ° C., which is the combustion temperature range of carbon, and holding the temperature at 400 to 600 ° C. for 2 to 3 hours. The carbon-derived black component can be removed by efficiently burning the component, and then by heating at a high temperature of 700 to 800 ° C. for 1 to 3 hours, impurities are removed without causing crystallization of silica. Purity can be increased.
　上述した様々な実施形態は、本発明によるガス化炉、ガス化炉の運転方法、及びバイオマスガス化処理方法の一具体例を説明したに過ぎず、当該記載により本発明の範囲が限定されるものではなく、各部の具体的構成は本発明の作用効果が奏される範囲で適宜変更設計可能であることはいうまでもない。 The various embodiments described above merely describe specific examples of the gasification furnace, the operation method of the gasification furnace, and the biomass gasification treatment method according to the present invention, and the description limits the scope of the present invention. Needless to say, the specific configuration of each part can be appropriately modified and designed within the range in which the effects of the present invention are exhibited.
１０：ガス化炉
２０：ガス精製装置
３０：ＦＴ合成反応器
１００：ＢＴＬプラント
Ｒ１：第１領域
Ｒ２：第２領域
  10: Gasifier 20: Gas purification device 30: FT synthesis reactor 100: BTL plant R1: 1st region R2: 2nd region

Claims (9)

  1. 　ケイ酸植物由来のバイオマスを原料とする非晶質シリカの製造方法であって、
    　前記バイオマスを熱分解処理してガス化するガス化ステップと、
    　前記ガス化ステップで生じたバイオマス残渣を焼成処理する焼成ステップと、
    を含む非晶質シリカの製造方法。     A method for producing amorphous silica using biomass derived from silicic acid plants as a raw material.
    A gasification step of pyrolyzing the biomass to gasify it,
    A firing step of firing the biomass residue generated in the gasification step, and a firing step.
    A method for producing amorphous silica including.
  2. 　前記ガス化ステップは、非晶質シリカが結晶化する相転移温度域より低い温度域でガス化するステップである請求項１記載の非晶質シリカの製造方法。 The method for producing amorphous silica according to claim 1, wherein the gasification step is a step of gasifying in a temperature range lower than the phase transition temperature range in which amorphous silica crystallizes.
  3. 　前記ガス化ステップは、前記バイオマス残渣の滞留時間が所定時間以下になるように調整される請求項２記載の非晶質シリカの製造方法。 The method for producing amorphous silica according to claim 2, wherein the gasification step is adjusted so that the residence time of the biomass residue is not more than a predetermined time.
  4. 　前記ガス化ステップで得られたガスから燃料を生成する燃料生成ステップを備えている請求項２または３記載の非晶質シリカの製造方法。 The method for producing amorphous silica according to claim 2 or 3, further comprising a fuel generation step of producing fuel from the gas obtained in the gasification step.
  5. 　前記焼成ステップの実行前に、前記ガス化ステップで生じたバイオマス残渣を粉砕処理する粉砕ステップを備えている請求項１から４の何れかに記載の非晶質シリカの製造方法。 The method for producing amorphous silica according to any one of claims 1 to 4, further comprising a crushing step of crushing the biomass residue generated in the gasification step before executing the firing step.
  6. 　前記焼成ステップは、前記バイオマス残渣を炭素の燃焼温度域で所定時間焼成する第１焼成ステップと、前記第１焼成ステップの後に前記相転移温度域より低い温度域で所定時間焼成する第２焼成ステップとを含む請求項１から５の何れかに記載の非晶質シリカの製造方法。 The firing step includes a first firing step in which the biomass residue is fired in a carbon combustion temperature range for a predetermined time, and a second firing step in which the biomass residue is fired in a temperature range lower than the phase transition temperature range for a predetermined time after the first firing step. The method for producing amorphous silica according to any one of claims 1 to 5, which comprises.
  7. 　請求項１から６の何れかに記載の非晶質シリカの製造方法に用いられる非晶質シリカの製造装置であって、
    　ケイ酸植物を含むバイオマスを熱分解処理してガス化するガス化炉と、
    　前記ガス化炉から排出された熱分解ガスとバイオマス残渣の混合物からバイオマス残渣を分離する分離機構と、
    　前記分離機構で分離されたバイオマス残渣を焼成して非晶質シリカを得る焼成炉と、
    を備えている非晶質シリカの製造装置。     A device for producing amorphous silica used in the method for producing amorphous silica according to any one of claims 1 to 6.
    A gasifier that pyrolyzes and gasifies biomass containing silicic acid plants,
    A separation mechanism that separates the biomass residue from the mixture of the pyrolysis gas and the biomass residue discharged from the gasification furnace, and
    A firing furnace that calcins the biomass residue separated by the separation mechanism to obtain amorphous silica.
    Amorphous silica manufacturing equipment.
  8. 　前記分離機構で分離されたバイオマス残渣を破砕する破砕機をさらに備えている請求項７記載の非晶質シリカの製造装置。 The amorphous silica manufacturing apparatus according to claim 7, further comprising a crusher for crushing the biomass residue separated by the separation mechanism.
  9. 　前記ガス化炉の後段には、前記ガス化炉で生成され前記分離機構で前記バイオマス残渣が分離された熱分解ガスから燃料を生成する反応装置を備えている請求項７または８記載の非晶質シリカの製造装置。
          The amorphous according to claim 7 or 8, wherein a reaction device for generating fuel from a pyrolysis gas produced in the gasification furnace and separated from the biomass residue by the separation mechanism is provided in the subsequent stage of the gasification furnace. Equipment for producing quality silica.
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Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2003529518A (en) * 2000-03-31 2003-10-07 アグリテック，インク． Precipitated silica and silica gel with or without deposited carbon from biomass ash solution and process
WO2007026680A1 (en) * 2005-08-31 2007-03-08 Kurimoto, Ltd. Amorphous silicon oxide powder and method for production thereof
CN103695015A (en) * 2014-01-06 2014-04-02 中盈长江国际新能源投资有限公司 Device and method for accelerating gas generating speed by biomass pyrolysis and obtaining nanoscale carbon dioxide material

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4259777B2 (en) * 2001-07-31 2009-04-30 井上 斉 Biomass gasification method
US7998448B2 (en) * 2006-10-27 2011-08-16 Kurimoto, Ltd. Amorphous silica and its manufacturing method
JP2008214158A (en) * 2007-03-06 2008-09-18 Maywa Co Ltd Process for manufacturing amorphous silica from chaff
CN101570315B (en) * 2009-06-15 2011-06-01 江苏大学 Method and device for producing hydrogen through biomass gasification by using single fluidized bed and two-step method
BRPI0905139A2 (en) * 2009-12-21 2011-08-09 Gomes Tairi Tonon Process for the production of high purity silica from rice husks
CN106829970A (en) * 2017-03-31 2017-06-13 章斐虹 A kind of method that rice husk prepares biomass nano silica
CN110423635B (en) * 2019-09-12 2020-06-19 吉林大学 Method for rice husk pyrolysis power generation and comprehensive utilization

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2003529518A (en) * 2000-03-31 2003-10-07 アグリテック，インク． Precipitated silica and silica gel with or without deposited carbon from biomass ash solution and process
WO2007026680A1 (en) * 2005-08-31 2007-03-08 Kurimoto, Ltd. Amorphous silicon oxide powder and method for production thereof
CN103695015A (en) * 2014-01-06 2014-04-02 中盈长江国际新能源投资有限公司 Device and method for accelerating gas generating speed by biomass pyrolysis and obtaining nanoscale carbon dioxide material

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