JP7262330B2 - Systems for producing adsorbents and methods of producing adsorbents - Google Patents

Description

One of the embodiments of the present invention relates to an adsorbent manufacturing system and an adsorbent manufacturing method. For example, one embodiment of the present invention relates to a system and method for producing a metal-loaded porous material that functions as an adsorbent.

In recent years, attempts have been made in various fields to reduce the burden on the environment by effectively utilizing organic matter, including organic wastes derived from plants and animals. For example, Patent Literature 1 discloses improving water quality by using a carbonized material in which calcium is supported on rice husks as a phosphate adsorbent. Patent Documents 2 and 3 disclose that a combustible gas obtained by gasifying organic waste (hereinafter referred to as dry distillation gas) is used to generate power.

JP-A-2007-75706 Japanese Patent Application Laid-Open No. 2004-352960 Japanese Patent Application Laid-Open No. 2006-87221

One of the embodiments of the present invention is to manufacture a metal-supporting porous material that functions as an adsorbent capable of adsorbing compounds containing phosphorus and arsenic with high efficiency and low cost, and at the same time generate electricity. One object is to provide a method for supplying energy and a system for realizing this method.

One embodiment of the invention is a system for manufacturing an adsorbent. The system comprises a gasification power plant, an immersion device for immersing the char in a liquid containing metal salts, and a reduction device for reducing the metal salt on the immersed char. The gasification power generation device has a gasification device for gasifying organic matter to produce a dry distillation gas and a carbide, and a power generation device for generating power using the dry distillation gas.

One embodiment of the invention is a method of making an adsorbent. This method includes gasifying organic matter to produce a dry distillation gas and a carbide, immersing the carbide in a liquid containing a metal salt to support the metal salt on the carbide, generating power using the dry distillation gas, carrying a It involves reducing the metal salt with a reducer using a portion of the carbonization gas.

According to the embodiments of the present invention, it is possible to efficiently and at low cost produce a metal-supporting porous material capable of adsorbing compounds containing phosphorus, nitrogen, arsenic, etc., and to simultaneously supply electric energy. It can contribute to the utilization and fixation of carbon dioxide in the atmosphere.

1 is a conceptual diagram showing the utilization of organic matter and the utilization and fixation of carbon dioxide realized by a system for manufacturing an adsorbent, which is one of the embodiments of the present invention. FIG. 1 is a block diagram of a system for manufacturing an adsorbent that is one embodiment of the present invention; FIG. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic cross-sectional view of a gasifier included in a system for manufacturing an adsorbent, which is one embodiment of the present invention; BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic cross-sectional view of a gasifier included in a system for manufacturing an adsorbent, which is one embodiment of the present invention; BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic cross-sectional view of a gasifier included in a system for manufacturing an adsorbent, which is one embodiment of the present invention; 1 is a block diagram of a power generator included in a system for manufacturing an adsorbent, which is one embodiment of the present invention; FIG. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic cross-sectional view of a heat exchanger included in a system for manufacturing an adsorbent, which is one embodiment of the present invention; BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic cross-sectional view of an immersion device included in a system for manufacturing an adsorbent, which is one embodiment of the present invention; BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic cross-sectional view of a drying device included in a system for manufacturing an adsorbent, which is one of the embodiments of the present invention; BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic cross-sectional view of a reduction device included in a system for manufacturing an adsorbent, which is one embodiment of the present invention; BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic cross-sectional view of a reduction device included in a system for manufacturing an adsorbent, which is one embodiment of the present invention; BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic cross-sectional view of a reduction device included in a system for manufacturing an adsorbent, which is one embodiment of the present invention; BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic cross-sectional view of a reduction device included in a system for manufacturing an adsorbent, which is one embodiment of the present invention;

Hereinafter, each embodiment of the present invention will be described with reference to the drawings and the like. However, the present invention can be implemented in various aspects without departing from the gist thereof, and should not be construed as being limited to the description of the embodiments illustrated below.

In the drawings, in order to make the description clearer, the width, thickness, shape, etc. of each part may be schematically represented compared to the actual embodiment, but this is only an example and limits the interpretation of the present invention. not something to do. In this specification and each drawing, elements having the same functions as those described with respect to the previous drawings may be denoted by the same reference numerals, and redundant description may be omitted.

Hereinafter, in this specification, biomass is a kind of organic matter, and refers to substances derived from living organisms and their metabolites. Examples include materials derived from trees. Specific examples include wood products such as plate-like or column-like wood, thinning wood, pruning waste wood, construction waste wood, powdered sawdust, and particle boats. There are no restrictions on the type of wood, and cedar, cypress, and bamboo may be used. Other examples include agricultural waste such as rice husks, bagasse, corn cobs and leaves, and agricultural by-products such as straw, straw and hay. Other examples include plants used as raw materials for fibers such as hemp, flax, cotton, sisal, abaca, and palm hair. Alternatively, algae such as seaweed may be used. Alternatively, silage derived from food residue and animal excreta can be used.

1. Overview FIG. 1 shows a system (hereinafter referred to as a , system) 100 is a conceptual diagram for explaining the utilization and fixation of carbon dioxide. Plants create biological resources by reducing carbon dioxide through photosynthesis and fixing it as various organic substances. Biological resources are used not only as an energy source (food) for other organisms, but also as functional and structural materials such as natural fibers and wood for various purposes. The system 100 makes effective use of organic residues and by-products, ie, biomass, which have been used in various ways to produce adsorbents and simultaneously create electrical energy. As a result, it is possible to contribute not only to the improvement of water quality through the use of adsorbents, but also to the fixation and utilization of carbon dioxide in the atmosphere.

Specifically, system 100 gasifies biomass to produce char and carbonization gas. Carbide is a porous body containing carbon as a main component, and functions as a support for metal contained in the adsorbent. Although the details will be described later, after the metal salt is adsorbed on the carbide to obtain a carbide (precursor carbide) on which the metal salt is supported, the supported metal salt is reduced to a metal (zero-valent metal) for adsorption. wood is obtained. This adsorbent is used for water pollutants in water bodies such as rivers, lakes, and seas, especially metal phosphates, metaphosphates, pyrophosphates, and phosphate esters such as phosphoric acid, calcium, iron, and aluminum. Phosphorus-containing compounds exemplified by organic phosphoric acids, metal salts of arsenic acid, metal salts of arsenous acid, metal salts of hydroarsenic acid, metal salts of meta-arsenous acid, or organic arsenic such as organic arsinic acids. It is possible to efficiently adsorb and fix compounds containing arsenic.

The dry distillation gas includes combustible or reducing gases such as hydrogen, carbon monoxide, methane, propane, and alkanes such as butane. System 100 utilizes both the flammability and reducing power of the carbonization gas. The former combustible gas is used for power generation by burning, contributing to the creation of electrical energy. Furthermore, exhaust heat generated during power generation can be used for drying the precursor carbide. On the other hand, the latter high-temperature dry distillation gas is used for reduction of the metal salt supported on the precursor carbide. This makes it possible to efficiently convert the precursor carbide into an adsorbent.

Generally, in biomass gasification power generation, high-temperature dry distillation gas of about 500 to 1300° C. is generated in the gasification furnace 124, which will be described later. Therefore, the dry distillation gas has a large thermal energy. In system 100, this thermal energy is also utilized in the production of adsorbents. For example, since the dry distillation gas used for the reduction reaction of the metal salt accounts for several percent of the total, heat energy is extracted from the surplus dry distillation gas, and this heat energy is used to dry the precursor carbide and reduce the metal salt. can be accelerated. As a result, the energy of the dry distillation gas can be efficiently used. Details of the system 100 are described below.

2. System FIG. 2 shows a block diagram for explaining the configuration of the system 100. As shown in FIG. The system 100 comprises a gasification power plant 110, an immersion device 180, and a reduction device 220 as a basic configuration. System 100 may further include drying apparatus 200 , reducing gas source 250 and flare stack 270 .

2-1. Gasification Power Generation Device The gasification power generation device 110 has a main function of carbonizing the biomass 102 to generate carbonized matter and dry distillation gas, and to generate power using the dry distillation gas. have. The gasification power plant 110 may further include a heat exchanger (first heat exchanger) 150, a gas purifier 160, a gas holder 166, a heat exchanger (second heat exchanger) 168, etc. as an arbitrary configuration. good.

(1) Gasifier The gasifier 120 is a device for carbonizing the biomass 102 to produce dry distillation gas and porous carbide 104 . There are no particular restrictions on the structure of the gasifier 120 . FIG. 3 shows a schematic cross-sectional view of an internal combustion gasifier as the gasifier 120 . The gasification apparatus 120 shown here is an example, and as will be described later, the gasification furnace 124 may be an external heat type, and its structure may be a batch type closed coal kiln, a continuous rotary kiln, or a rocking gas furnace. A gasification furnace, a screw furnace, a fixed bed furnace (downdraft, updraft), etc. may also be used. Either type has a flow path for introducing dry distillation gas generated by carbonization into the reduction device 220 .

As shown in FIG. 3, the gasifier 120 has a rotary gasifier 124 with a cylindrical shape and a heating chamber 122 with burners 130 that supply thermal energy for carbonizing the biomass 102 . It is provided so as to cover the gasification furnace 124 . The gasifier 120 may be provided with a hopper 134 for charging the biomass 102 to be carbonized and a screw feeder 136 positioned below the hopper 134 . Biomass 102 is continuously fed into gasifier 124 by screw feeder 136 .

The gasification furnace 124 exemplified here is a rotary kiln type gasification furnace, and the gasification furnace 124 and the heating chamber 122 are arranged from a horizontal plane so that the side where the biomass 102 is introduced is higher than the side where the carbide 104 is carried out. Inclined. Gasifier 124 is configured to rotate within heating chamber 122 by drive 126 . The drive unit 126 rotates the gasification furnace 124 around the central axis of the heating chamber 122 using, for example, chains, belts, and gears. The biomass 102 supplied to the gasification furnace 124 is transported from the hopper 134 side to the burner 130 side by the continuous rotation of the gasification furnace 124. concentration), heated by heat from burner 130 at a temperature of about 400°C to 1300°C. As a result, the carbonization of the biomass 102 progresses and a dry distillation gas is generated. The dry distillation gas is taken out from the exhaust duct 138 and then supplied to the reduction device 220 and the power generation device 170 through the first gas supply pipe 128 . The resulting carbide 104 is carried out of the gasifier 120 from the bottom of the gasification furnace 124 via a rotary valve 132 for preventing gas leakage, and is dipped in the dipping device 180 . Depending on the case, the rotary valve 132 may be installed in two stages, upper and lower, in which case the upper and lower rotary valves are alternately opened to discharge the carbide. Also, a mechanism capable of cooling the rotary valve 132 may be provided around the rotary valve 132 .

In order to maintain the temperature of the dry distillation gas, the first gas supply pipe 128 may be covered with a heat insulating means 140 such as a heat insulating material. Alternatively, the first gas supply pipe 128 may be provided with a heating device (not shown) for heating the dry distillation gas generated by the gasifier 120 or for maintaining the temperature. By providing the heat retaining means 140 and/or the heating device, the dry distillation gas can be supplied to the reducing device 220 while maintaining a high temperature, and the metal salt can be efficiently reduced.

As an optional configuration, a mechanism for supplying oxygen to the carbonized gas to be produced may be provided. FIG. 3 shows an example in which an introduction port 148 for introducing oxygen or air is provided in the exhaust duct 138 via a valve 142 as this function. By adding a small amount of oxygen to the carbonization gas, the temperature of the gasifier 120 can be controlled, typically increased, and the tar contained in the carbonization gas is burned to reduce the concentration of tar in the carbonization gas. can do. Note that if the amount of oxygen supply is too large, the biomass 102 will burn and the carbide cannot be obtained, so it is preferable to control the amount of oxygen supply. Although not shown, a reforming furnace for removing tar by a steam reforming reaction is connected to the first gas supply pipe 128 as a tar separator, and after removing the tar, the dry distillation gas is transferred to the heat exchanger 150 or to power generation. It may be supplied to the device 170, the reducing device 220, or the like.

As another example of the gasifier 120, an external combustion gasifier is shown in FIG. As shown in FIG. 4, the external combustion gasifier 120 basically has a gasification furnace 124 and a heating chamber 122 surrounding the gasification furnace 124 . The heating chamber 122 is provided so as to form a space with the gasification furnace 124 , and the heating chamber 122 is provided with a heat medium inlet 144 and a heat medium outlet 146 connected to this space. An externally heated heat medium is introduced into this space via the former, and the heat medium is discharged from the latter. As a result, the heated heat medium comes into contact with the outer wall of the gasification furnace 124, and the gasification furnace 124 is heated. As the heat medium, gas heated by an electric heater or the like may be used, or high-temperature gas obtained by burning fuel such as light oil, heavy oil, or carbide may be used. Alternatively, dry distillation gas generated by gasification may be used. When using such an external combustion gasifier 120, although an energy source for heating the heat medium is required, the carbide 104 can be obtained with a relatively high yield.

As another example of the gasifier 120, a fixed-bed gasifier is shown in FIG. A gasification apparatus 120 shown in FIG. 5 has a continuous furnace type gasification furnace 124 , and a heater 131 for heating the gasification furnace 124 is provided around the gasification furnace 124 . A rotary valve 133 is provided above the gasification furnace 124 . Instead of the rotary valve 133, a screw feeder 136 (see FIGS. 3 and 4) may be provided. The introduction port 148 for introducing oxygen or air can be installed at any location, and is provided below the gasification furnace 124 in the example shown in FIG. The bottom of the gasifier 124 may be slanted (see dashed line in FIG. 5), and this structure allows the carbides 104 that form in the gasifier 124 to collect at the bottom of the gasifier 124 .

Biomass 102 is introduced from hopper 134 into gasifier 124 , and oxygen or air is introduced into gasifier 124 through inlet 148 . The biomass 102 is carbonized by the heat from the heater 131 to produce dry distillation gas and porous carbonized matter 104 . A dry distillation gas is taken out from a first gas supply pipe 128 connected to the gasification furnace 124 and introduced into the heat exchanger 150 and/or the reduction device 220 . By using the gasifier 120 shown in FIG. 5, the tar content accompanying the carbonization gas can be reduced. If the inside of the gasification furnace 124 reaches a sufficient temperature during gasification, the heater 131 can be omitted.

(2) Power Generation Device The structure and type of the power generation device 170 are not restricted, and a gas turbine type, gas engine type, or dual fuel engine type power generation device can be used as appropriate. For example, in the case of a gas engine system, as shown in the block diagram of FIG. The generator 170 is configured by the generator 176 and the like. Electrical energy is output from transformer 176 . Optionally, the power plant 170 may include a cooler 178 for cooling the gas engine 172 to obtain thermal energy produced by the gas engine 172 . The heat energy obtained by the cooler 178 can be supplied to the drying device 200 or the reducing device 220 through a gaseous or liquid heat transfer medium. Although not shown, a compression device for compressing the dry distillation gas and supplying it to the gas engine 172 may be provided. Although the configuration in which the gas engine 172 and the generator 174 are separated has been described here, the power generator 170 may have a configuration in which the generator and the gas engine are integrated.

(3) Heat Exchanger The heat exchanger 150 is connected to the first gas supply pipe 128 of the gasifier 120 and provided to cool the high-temperature dry distillation gas and take out heat energy. There are no restrictions on the type and structure of the heat exchanger 150, and various types such as plate type, shell-tube type, and fin-tube type can be applied. The heat exchanger 150 illustrated in FIG. 7 is a shell-and-tube heat exchanger. The heat exchanger 150 has an outer shell 152, and the outer shell 152 is provided with an inlet 154 and an outlet 156 for introducing and discharging the dry distillation gas, respectively. A flow path for the carbonization gas is formed in the outer shell 152 and connected to an inlet 154 and an outlet 156 . Fins 158 may be provided within the outer shell 152 to allow the heat transfer medium to efficiently contact the flow path.

The heat transfer medium may be gas such as air or nitrogen, water, alcohol such as ethylene glycol, silicone oil, or aromatic compound such as biphenyl or diphenyl ether. These heat transfer media are injected into the outer shell 152, contact with the flow path to exchange heat with the dry distillation gas, and then are taken out to the outside. When the heat transfer medium is gas such as air or nitrogen, the heat transfer medium heated by heat exchange can be directly introduced into the chamber 202 of the drying apparatus 200 or the reduction furnace 222 (described later) of the reduction apparatus 220 . On the other hand, when the heat transfer medium is liquid, it is supplied to the drying device 200 and the reduction device 220 so as to circulate inside the tube heater 216 provided around the chamber 202 . When the heat transfer medium is a liquid, the heat exchanged liquid heat transfer medium is again heat-exchanged with a gas such as air or nitrogen in a heat exchanger different from the heat exchanger 150, and the heated gas is sent to the drying device. It can be introduced into the chamber 202 of 200 or the reduction furnace 222 of the reduction device 220 .

(4) Other Configurations There are no restrictions on the configuration of the gas purification device 160, and for example, it can include a steam concentrator 162, a dust filter 164, a scrubber (not shown), a desulfurization device, and the like. By appropriately providing these structures, ammonia, hydrogen cyanide, hydrochloric acid, dust, dioxin, sulfur oxides, nitrogen oxides, hydrogen sulfide, and the like contained in the dry distillation gas are removed. The gas holder 166 can be provided to store the dry distillation gas, and is configured using a variable volume type or constant volume type gas holder. The type and capacity of gas holder 166 are appropriately adjusted according to the scale of system 100 . The heat exchanger 168 has a function of cooling the dry distillation gas supplied to the power generator 170, and its structure can also be arbitrarily selected. For example, heat exchanger 168 may have the same or similar construction as heat exchanger 150 .

The flare stack 270 is provided for burning the surplus dry distillation gas introduced into the reduction device 220 . In the present system 100, the surplus dry distillation gas supplied to the reduction device 220 may be introduced into the power generation device 170 via the heat exchanger 168 and combusted to be reused for power generation (see FIG. 2). Since the dry distillation gas used for the reduction reaction of the metal salt accounts for several percent of the total, the excess dry distillation gas is introduced into the power generation device 170 via the heat exchanger 168 to efficiently use the thermal energy of the dry distillation gas. be able to. Furthermore, since the temperature of the gas discharged from the reduction device 220 is lowered, the load on the heat exchanger 168 can be reduced and the size of the heat exchanger 168 can be reduced.

2-2. Immersion Apparatus Carbide 104 obtained by carbonization is immersed in an immersion apparatus 180 and metal salts are adsorbed in the pores and/or on the surface of the carbide 104 . There are no restrictions on the structure of the immersion device 180, and basically a tank 182 for storing a suspension or solution containing a metal salt used for immersion (hereinafter collectively referred to as a liquid containing a metal salt or an immersion liquid). (Fig. 8). A discharge port may be provided at the bottom of the tank 182, and the immersion liquid can be stored and discharged by opening and closing a valve 190 connected to the discharge port. As an optional configuration, the tank 182 may further include a stirring device 192, a heater 196 for heating the immersion liquid, a cooling device for cooling the immersion liquid, an ultrasonic irradiation device (not shown), and the like. The immersion liquid is stirred by using the stirring device 192, and the concentration distribution of the metal salt in the immersion liquid can be reduced. Agitation of the immersion liquid may be performed by circulating the immersion liquid. The heater 196 has a heating element inside and may be configured to be electrically heated, or may have a hollow structure in which a heat transfer medium supplied from the heat exchangers 150 and 168 is circulated. It may be configured to allow By irradiating the immersion liquid with ultrasonic waves from the ultrasonic irradiation device during immersion, the immersion liquid can be efficiently permeated into the pores of the carbide 104 . The immersion device 180 may further include a lid 184 having one or more through holes 186 therein. The through-hole 186 includes, for example, a gas source for introducing gas such as nitrogen, argon, and air, a decompression device for evacuating the inside of the tank 182, a pressurization device for pressurizing the inside of the tank 182, and a A pressure gauge, a thermometer, or the like for measuring pressure or temperature may be connected.

Since the carbide 104 has a lower specific gravity than water, it floats on the immersion liquid. Therefore, a case 194 that can be accommodated in the tank 182 may be used in combination with the immersion device 180 . The case 194 is provided with a plurality of openings and is constructed of material and structure such that it has a higher specific gravity than the immersion liquid. The plurality of openings are set so that the mesh size is smaller than that of the carbide 104 . This not only prevents the carbides 104 from floating on the immersion liquid and preventing sufficient contact with the immersion liquid, but also allows the immersed carbides 104 to be easily recovered, and the carbides 104 to be removed from the case 194 . can be prevented from leaking out. Separation of the carbide 104 and the immersion liquid is performed by a dehydrator or the like installed after the immersion device 180 . As the dehydrator, for example, a conventionally known dehydrator such as a centrifugal dehydrator can be appropriately used.

2-3. Drying Apparatus By immersing the carbide 104, a precursor carbide 106 carrying a metal salt is obtained. The drying device 200 is a device having a function of drying the precursor carbide 106, and its structure is not restricted. For example, as shown in FIG. 9, a drying apparatus 200 includes a chamber 202 containing a precursor carbide 106 and provided with one or more drying gas inlets 206 and gas outlets 210 . The dry gas supply port 206 is connected to the heat exchanger 150 or the heat exchanger 168, whereby the gaseous heat transfer medium supplied from the heat exchanger 150 or the heat exchanger 168 is introduced into the chamber 202. . The gaseous heat transfer medium is flow controlled using valve 208 . As a result, the thermal energy of the high-temperature dry distillation gas generated in the gasification device 120 can be supplied to the drying device 200, and the energy during gasification can be efficiently reused. This contributes to the reduction of the manufacturing cost of the adsorbent. The system 100 may be configured to supply the heat energy obtained by the cooler 178 to the drying device 200 via a heat transfer medium.

Alternatively, a tube heater 216 for circulating a separately heated heat transfer medium or a heat transfer medium supplied from the heat exchangers 150 and 168 may be provided outside or inside the chamber 202 . FIG. 9 shows an example in which the tube heater 216 is installed outside the chamber 202 . In this case, a liquid heat transfer medium can be used in the heat exchangers 150,168. Optionally, the drying apparatus 200 may include a separator 214 to prevent contact between the bottom of the chamber 202 and the precursor charcoal 106, a lid 204, or a drain (not shown). One or more through holes 212 may be provided in the lid 204 . For example, a thermometer or a pressure gauge may be installed in the through-hole 212 , and a decompression device for promoting drying may be connected to the chamber 202 through the through-hole 212 .

2-4. Reduction Device The reduction device 220 has a function of reducing the metal salt supported on the dried precursor carbide 106 to metal. The structure of the reduction device 220 is also not particularly limited, and for example, a continuous furnace structure schematically shown in FIG. 10 can be adopted. The reduction apparatus 220 shown here includes a reduction furnace 222, a heater 228 for heating the reduction furnace 222, and a first gas supply pipe for introducing the dry distillation gas supplied from the gasifier 120 into the reduction furnace 222. 128. The first gas supply pipe 128 is provided with a valve 234 for controlling the flow rate of the reducing gas. As an optional configuration, a heater 246 for heating the dry distillation gas may be provided so as to cover the first gas supply pipe 128 .

The reducing furnace 222 may be provided with a rotary valve 226 and a hopper 224 for charging the precursor carbide 106 . A rotary valve 230 can be provided at the bottom of the reduction furnace 222 for removing the resulting adsorbent. Also, each of the rotary valves 226, 230 may be configured with two rotary valves to have a two-stage configuration. By providing the two rotary valves 226 and 230, it is possible to prevent leakage of the dry distillation gas introduced into the reducing furnace 222, and to reduce the metal salt safely. Moreover, by installing these, the precursor carbide 106 can be continuously put into the reduction furnace 222 and the adsorbent obtained by the reduction can be taken out. Note that the bottom of the reduction furnace 222 may be inclined (see the dotted line in FIG. 10), and this structure allows the adsorbent to be collected at the bottom of the reduction furnace 222 . The reducing furnace 222 is further provided with a gas collecting pipe 244 , and the dry distillation gas that has reacted with the precursor carbide 106 or excess dry distillation gas is discharged through the gas collecting pipe 244 .

The reducing device 220 may further have a second gas supply pipe 240 for separately supplying reducing gas. A reducing gas source 250 is connected to the second gas supply pipe 240 ( FIG. 2 ), and the flow rate of the reducing gas is controlled by a valve 242 . As a result, for example, when the amount of reducing gas generated in the gasifier 120 is insufficient, or even when the gasifier 120 is not in operation, a sufficient amount of reducing gas is supplied into the reducing device 220 to produce precursors. A reduction treatment can be performed on the carbide 106 . The reducing gas supplied from the reducing gas source 250 may be hydrogen, carbon monoxide, alkane, or a mixture thereof. Alternatively, the reducing gas may be mixed with an inert gas such as nitrogen or argon. Alternatively, the precursor carbide 106 may be heat treated in an oxygen-free or inert gas atmosphere. Due to the heat treatment, carbon, oxygen, hydrogen, or sulfur contained in the precursor carbide 106 reacts to form a reducing gas. The reducing gas reduces the precursor carbide 106 .

The reduction device 220 may further include a third gas supply pipe 236 connected to a gas replacement device (not shown) for replacing the atmosphere (gas) in the reduction furnace 222 . Since the dry distillation gas contains combustible gases such as hydrogen and alkanes and toxic gases such as carbon monoxide, air, nitrogen, or rare gas ( Helium, argon, etc.) can be supplied to discharge the residual dry distillation gas from the reduction furnace 222 . A gas source (not shown) such as air, nitrogen, or argon is connected to the gas replacement device. Alternatively, the gas replacement device may be a fan or compressor for introducing outside air. Furthermore, the first gas supply pipe 128, the second gas supply pipe 240, and the third gas supply pipe 236 are not connected to the reduction furnace 222 independently, but are connected to the reduction furnace 222 as a single supply pipe. I don't mind. In this case, these gas supply pipes are connected outside the reduction furnace 222, and the supply of these gases is controlled by switching valves.

The reductor 220 need not be continuous and may be batchwise. For example, as shown in FIG. 11, instead of the rotary valve 226, an opening/closing door 223 is provided at the opening of the reducing furnace 222. Using this, the precursor carbide 106 is introduced into the reducing furnace 222, and the generated adsorbent is taken out. good too. Although not shown, a plurality of openings may be provided, and the charging of the precursor carbide 106 and the taking out of the adsorbent may be performed via different openings. Further, in the example shown in FIG. 11, the reducing apparatus 220 is configured such that the precursor carbide 106 is introduced from above the reducing furnace 222 through the opening. Device 220 may be configured.

Alternatively, as shown in FIG. 12, the reduction device 220 may be a rotary kiln type reduction device. That is, the reduction apparatus 220 includes a rotary reducing furnace 222 having a cylindrical shape and a heating chamber 221 covering the reducing furnace 222, and the reducing furnace 222 may be configured to rotate within the heating chamber 221 by a drive unit 232. good. The temperature inside the reduction furnace 222 is controlled by a burner 231 provided in the heating chamber 221 . The dry distillation gas is supplied from the gasification furnace 124 via the first gas supply pipe 128 . The reductor 220 may also be configured to receive a supply of reducing gas from a reducing gas source 250 . The heating chamber 221 is provided with a gas collection tube 244 through which gas generated after the precursor carbide 106 reacts with the dry distillation gas or excess dry distillation gas is discharged.

The precursor carbide 106 supplied to the reducing furnace 222 through the screw feeder 225 is transported from the hopper 224 side to the burner 231 side by the continuous rotation of the reducing furnace 222 . In the atmosphere of the dry distillation gas, the precursor carbide 106 is heated by the heat of the burner 231, thereby reducing the metal salt supported on the precursor carbide 106 and generating an adsorbent.

Alternatively, as shown in FIG. 13, an external combustion reducing device 220 can be used. The external combustion type reduction device 220 shown in FIG. 13 has a reduction furnace 222 rotated by a drive unit 232 and a heating chamber 221 covering it. A space is formed between the reduction furnace 222 and the heating chamber 221 , and a heat medium inlet 227 and a heat medium outlet 229 are provided in the space in the heating chamber 221 . The heating of the reducing furnace 222 may be carried out in the same manner as the external combustion gasifier 120 described above, or the dry distillation gas may be introduced inside the reducing furnace 222 and between the heating chamber 221 and the reducing furnace 222. good too. In the latter case, the dry distillation gas is introduced from the first gas supply pipe 128 and/or the heat medium inlet 227, respectively.

As will be described later, in the system 100, the dry distillation gas that has been used for reduction processing in the reduction device 220 can be introduced into the power generation device 170 to generate power. In order to generate power using the gas, it is necessary to cool the dry distillation gas to about 50° C. in the heat exchanger 168 . Since the temperature of the dry distillation gas introduced between the heating chamber 221 and the reduction furnace 222 is lowered, by introducing the gas discharged from the heat medium discharge port 229 into the heat exchanger 168, the heat exchanger 168 This is preferable because it can reduce the load on That is, one of the advantages of the system 100 is that the reduction device 220 can be used like a heat exchanger.

Although not shown, the system 100 is configured such that a tube heater for circulating the heat transfer medium supplied from the heat exchanger 150 or the like is provided outside the reduction furnace 222 to heat the reduction furnace 222, similar to the drying apparatus 200. You may This also makes it possible to utilize the thermal energy of the dry distillation gas for reduction of the precursor carbide 106 via the heat transfer medium. Note that drying and reduction of precursor carbide 106 may be performed in reduction device 220 without providing drying device 200 in system 100 .

3. System Flow The flow of power generation using the system 100 and the production of the adsorbent will be specifically described below.

3-1. Carbonization First, biomass 102 is placed in gasifier 120 using hopper 134 and screw feeder 136 (FIGS. 3-5). In the gasifier 124, the biomass 102 is carbonized by the energy obtained by the burners 130 or the heated heat medium in the absence of oxygen or in the presence of low concentrations of oxygen. During carbonization, part of the biomass 102 becomes high temperature (700° C. to 1300° C.) dry distillation gas containing at least water vapor, carbon monoxide, hydrogen, or alkanes, and the residue becomes the char 104 . Carbonized gas has reducing power and combustibility possessed by hydrogen, carbon monoxide, etc., and thermal energy due to high temperature. The carbide 104 is a porous material in which pores of various sizes are formed in which pores due to the structure of the biomass 102 and pores generated by desorption of dry distillation gas are intricately mixed. All or part of the obtained carbide 104 is subjected to the immersion treatment. If not all of the carbide 104 is used, another portion can be used for various purposes.

Part of the dry distillation gas generated during this carbonization is transported to the reduction furnace 222 of the reduction device 220 via the first gas supply pipe 128 . As a result, the thermal energy and reducing power of the dry distillation gas are supplied to the reducing device 220 . Meanwhile, the remaining carbonized gas is introduced into the heat exchanger 150 to be cooled and at the same time heat the heat transfer medium used in the heat exchanger 150 . That is, part of the thermal energy of the dry distillation gas is transferred to the heat transfer medium.

3-2. Power Generation The cooled dry distillation gas is supplied to the power generation device 170 via the gas purification device 160 and the like (see FIG. 2). The dry distillation gas is used to drive the gas engine 172 in the power generator 170, thereby generating power. Thus, in system 100, carbonization gas is removed from biomass 102 and electrical energy is created using the combustibility of the carbonization gas. Considering that the biomass 102 is an organic substance obtained by photosynthesis, that is, by fixing carbon dioxide, it can be said that this process of power generation is creation of energy indirectly using the fixed carbon dioxide.

3-3. Soaking and Drying All or part of the char 104 obtained by carbonizing the biomass 102 is subjected to a soaking treatment in a soaking device 180 . As a result, the metal salt is adsorbed on the pore walls and surface of the carbide 104 to obtain the precursor carbide 106 .

Precursor carbide 106 is then dried using drying apparatus 200 . As mentioned above, part of the thermal energy of the carbonized gas is transferred in heat exchanger 150 to the heat transfer medium. The heated heat transfer medium is introduced into the chamber 202 of the drying apparatus 200 or into a tube heater 216 provided in the chamber 202 . Thus, in system 100, a portion of the thermal energy of the carbonization gas is utilized for drying precursor carbide 106 via a heat transfer medium. The thermal energy used at this time is the thermal energy of the dry distillation gas obtained by carbonization of a batch different from the carbonization of the biomass 102 which is the raw material of the precursor carbonized material 106 to be dried. Therefore, if other batches of carbonized precursor 106 are not dried during carbonization of biomass 102, the entire amount of dry distillation gas is supplied to heat exchanger 150 and stored in gas holder 166, or It can be used for power generation. On the other hand, if carbonization is not performed during drying of precursor carbide 106 , a separately heated heat transfer medium may be supplied to chamber 202 and tube heater 216 .

3-4. Reduction The dried precursor carbide 106 is subjected to a reduction treatment in a reduction device 220 to reduce the metal salt to metal to obtain an adsorbent. Reduction is performed by heating the reduction furnace 222 and supplying a reducing gas. At this time, part of the dry distillation gas generated in the gasifier 120 can be used. Specifically, the valve 234 is opened and the dry distillation gas is introduced into the reduction furnace 222 from the first gas supply pipe. The carbonized gas immediately after being produced has a high temperature and contains gases having reducing power such as hydrogen and carbon monoxide. Therefore, by supplying the dry distillation gas into the reduction furnace 222 , the thermal energy and reducing power of the dry distillation gas can be utilized in the reduction of the precursor carbide 106 . The system 100 may also use the thermal energy of the heat transfer medium provided by the heat exchangers 150 and 168 to heat the reduction furnace 222 . The adsorbent can be manufactured by the above process.

Note that drying may be performed using the reducing device 220 without providing the drying device 200 . In this case, an inert gas is introduced into the reduction furnace 222 to dry the precursor carbide 106 . Alternatively, the screw feeder 225 side of the reducing furnace 222 may be the drying area and the burner 231 side may be the reducing area, and the drying process and the reducing process may be performed simultaneously in the reducing device 220 . Furthermore, two reducing devices 220 may be connected in series, one reducing device 220 performing the drying process, and the other reducing device 220 performing the reducing process.

When the precursor carbide 106 is reduced in an inert gas atmosphere or an atmosphere with a low oxygen concentration, the counter ion of the metal salt in the precursor carbide 106 reacts with the carbon constituting the precursor carbide 106 by heating. As a result, carbon monoxide or hydrogen is produced. For example, in the case of the precursor carbide 106 containing iron sulfate, sulfurous acid gas generated by heating reacts with carbon in the precursor carbide 106 to produce carbon monoxide and sulfur trioxide. Alternatively, the oxygen and carbon in the precursor carbide 106 react to form carbon monoxide. Alternatively, the water contained in the precursor carbide 106 is thermally decomposed to produce methane and hydrogen. Carbon monoxide, sulfur dioxide, sulfur trioxide, methane, or hydrogen may be used to reduce the precursor carbide 106 . However, if the precursor carbide 106 is reduced in the presence of sulfur oxide gas, by-products may be generated. The reduction treatment may be performed after replacing the inside of the furnace 222 with an inert gas.

As in the drying process, the thermal energy and reducing power used during reduction are the thermal energy and reduction of the dry distillation gas obtained by carbonization of a batch different from the carbonization of the biomass 102, which is the raw material of the precursor carbonized material 106 subjected to reduction. Power. Therefore, if the carbonization of the biomass 102 does not involve the reduction of other batches of precursor charcoal 106, the entire amount of dry distillation gas is supplied to the heat exchanger 150 and stored in the gas holder 166, or It can be used for power generation. On the other hand, if carbonization is not performed during the reduction of the precursor carbide 106 , the reducing furnace 222 is heated using the heater 228 and the reducing gas is supplied from the reducing gas source 250 to the reducing furnace 222 .

As described above, in the system 100, not only the carbonized material produced by the carbonization of the biomass 102, but also the thermal energy of the dry distillation gas is used for drying and reducing the precursor carbonized material 106, and the reducing power is used for reducing the precursor carbonized material 106. can be done. Therefore, it is not necessary to separately supply thermal energy or reducing gas from the outside for drying or reducing the precursor carbide 106, or even if supplied, the cost can be greatly reduced. Therefore, the adsorbent can be efficiently manufactured at low cost. Furthermore, in the system 100, the combustibility of the dry distillation gas after the use of thermal energy can be used to generate electricity and create electric energy.

Looking at the flow of the system 100 from another perspective, this flow is that the dry distillation gas generated by the pyrolysis of the biomass 102 under anoxic conditions is used for the reduction of metal compounds and power generation, and the non-gasified residue is A process in which some char 104 is converted into an adsorbent. Organic matter such as biomass is produced by fixing carbon dioxide in the atmosphere using light energy and water as an electron donor. In addition, since the adsorbent produced in this flow adsorbs compounds containing phosphorus after being used to improve water quality, it can be reused for soil fertilization by burying it in agricultural land. . Therefore, the system 100 not only contributes to the improvement of water quality, but also can fix carbon dioxide in the atmosphere, and can be positioned as one of the effective means for countermeasures against the greenhouse effect.

4. Manufacture of Adsorbent A method of manufacturing an adsorbent using the system 100 will now be described in detail.

4-1. Carbonization First, the biomass 102 as a raw material is installed in the gasification furnace 124 of the gasification device 120 . Biomass 102 may be introduced via hopper 134 and transported inside gasifier 124 by screw feeder 136 . The biomass 102 may be any material that provides a porous carbonized product by carbonization, and typical examples thereof include wood and fiber waste. Heating is performed using a burner 130 or by supplying a heat medium so that the temperature in the gasification furnace 124 is 400° C. or more and 1300° C. or less. At least part of the dry distillation gas generated by carbonization is supplied to the power generator 170 via the heat exchanger 150 and used for power generation. It should be noted that the heat generated in the heat exchangers 150, 168 may be used to dry the biomass 102 prior to carbonization of the biomass 102. This allows the biomass 102 to be carbonized with less energy in the gasifier 120 .

4-2. Immersion The resulting carbide is immersed in an immersion liquid. The metal salts include sulfates, nitrates, and hydrochlorides of iron, nickel, cobalt, vanadium, manganese, magnesium, calcium, etc. Among them, iron sulfates that provide metals capable of efficiently fixing compounds containing phosphorus or arsenic. , nitrates and hydrochlorides are preferred. Specific examples include ferrous sulfate, ferric sulfate, ferrous nitrate, ferric nitrate, ferrous chloride, and ferric chloride. Also, a polyferric sulfate solution can be used. The concentration of the metal salt in the immersion liquid can be, for example, 1% or more and 80% or less by weight, or 15% or more and 60% or less by weight. As a solvent for the immersion liquid, water and alcohol can be used, but water is preferable because it is low in toxicity, non-flammable and inexpensive. The temperature of the immersion liquid during immersion may be adjusted to 0°C to 150°C, 0°C to 100°C, or 0°C to 70°C. The immersion liquid may be replaced for each batch, but may be replaced for each batch. That is, the dipping liquid may be reused in multiple batches.

By repeating the immersion of the carbide 104, the metal salt concentration gradually decreases. Therefore, the immersion liquid after immersion may be concentrated. At this time, the heat transfer medium supplied from the heat exchangers 150 and 168 may be used as the heat energy required for concentration. In this case, for example, a heat transfer medium supplied from the heat exchangers 150 and 168 is circulated in the heater 196 to heat the immersion liquid, thereby performing the concentration. As a result, the immersion liquid is concentrated by indirectly utilizing the thermal energy of the dry distillation gas.

The immersion may be performed after cooling the carbide 104 to room temperature, or may be performed while the temperature is high. For example, the immersion temperature is preferably 0° C. to 150° C., 0° C. to 100° C., 0° C. to 90° C., or 0° C. to 70° C. The immersion time can be selected arbitrarily, and is preferably 1 minute or longer. The immersion may be performed while irradiating ultrasonic waves to the immersion liquid, or the immersion may be performed after reducing the pressure, followed by pressurization. The immersion may be performed under normal pressure, or may be performed under reduced pressure or increased pressure. For example, the pressure in the chamber 202 is -0.1 MPa or more and 0.9 MPa or less, -0.1 MPa or more and 0.40 MPa or less, or -0.1 MPa or more and 0.1 MPa or less in gauge pressure (pressure difference with respect to atmospheric pressure). do it. Moreover, when pressurizing after depressurization, it can be carried out at a gauge pressure of 0 MPa or more and 0.9 MPa or less, or 0 MPa or more and 0.4 MPa or less as a gauge pressure with the atmospheric pressure being zero.

4-3. Drying After soaking, the resulting precursor carbide 106 is dried. Drying may be performed at room temperature, but may be performed at a temperature higher than room temperature using the thermal energy of the dry distillation gas obtained by carbonizing the biomass 102 of another batch as described above. That is, the heat energy of the heat transfer medium obtained by the heat exchangers 150 and 168 or the cooler 178 can be used to set the chamber 202 to an arbitrary temperature. For example, drying may be performed by setting the temperature to be selected from the range of 50° C. to 250° C. or 60° C. to 200° C.

4-4. Reduction After drying, the precursor carbide 106 is introduced into the reduction furnace 222 of the reduction device 220 . Also, another batch of biomass 102 is installed in the gasifier 124 of the gasifier 120 and gasification is started. Part of the dry distillation gas obtained by gasification is introduced into the reduction furnace 222 through the first gas supply pipe 128 . If necessary, the heater 228 is driven to heat the reduction furnace 222 . The introduction amount of the dry distillation gas and the heater 228 are adjusted so that the temperature of the reduction furnace 222 is 200° C. or higher and 1200° C. or lower, 400° C. or higher and 1200° C. or lower, or 600° C. or higher and 900° C. or lower. If the amount of the dry distillation gas is insufficient, the reducing gas may be separately introduced from the reducing gas source 250 .

Reduction can be monitored and controlled using the concentration of reducing gas in the exhaust gas from gas collection tube 244 . Specifically, when the concentration of the reducing gas in the exhaust gas is low, it may be determined that it is necessary to increase the introduction amount of the dry distillation gas or to introduce the reducing gas from the reducing gas source 250 . Alternatively, it may be determined that the reduction is completed when the concentration of the reducing gas becomes constant. By this reduction treatment, at least part of the metal salt in the carbide is reduced to a zero-valent metal, and the adsorbent is obtained.

According to the above-described method, a metal-supporting porous material capable of adsorbing a compound containing phosphorus or arsenic can be produced efficiently and at low cost, using an organic substance such as biomass as a starting material, while simultaneously supplying electric energy. becomes possible.

Each of the embodiments described above as embodiments of the present invention can be implemented in combination as appropriate as long as they do not contradict each other. Appropriate additions, deletions, or design changes made by those skilled in the art based on each embodiment are also included in the scope of the present invention as long as they have the gist of the present invention.

Even if there are other actions and effects different from the actions and effects brought about by each of the above-described embodiments, those that are obvious from the description of the present specification or those that can be easily predicted by those skilled in the art are of course the present invention. is understood to be brought about by

100: System, 102: Biomass, 104: Carbide, 106: Precursor carbide, 110: Gasification power plant, 120: Gasification device, 122: Heating chamber, 124: Gasification furnace, 126: Actuator, 128: Third 1 gas supply pipe, 130: burner, 131: heater, 132: rotary valve, 133: rotary valve, 134: hopper, 136: screw feeder, 138: exhaust duct, 140: heat retaining means, 142: valve, 144: heat Medium inlet, 146: heat medium outlet, 148: inlet, 150: heat exchanger, 152: outer shell, 154: inlet, 156: outlet, 158: fins, 160: gas refiner, 162: steam concentrator , 164: dust filter, 166: gas holder, 168: heat exchanger, 170: power generator, 172: gas engine, 174: generator, 176: transformer, 178: cooler, 180: immersion device, 182: tank, 184: lid, 186: through-hole, 190: valve, 192: stirrer, 194: case, 196: heater, 200: drying device, 202: chamber, 204: lid, 206: dry gas supply port, 208: valve, 210: Gas outlet, 212: Through hole, 214: Separator, 216: Tube heater, 220: Reduction device, 221: Heating chamber, 222: Reduction furnace, 223: Open/close door, 224: Hopper, 225: Screw feeder, 226 : Rotary valve 227: Heat medium inlet 228: Heater 229: Heat medium outlet 230: Rotary valve 231: Burner 232: Actuator 234: Valve 236: Third gas supply pipe 240 : second gas supply pipe, 242: valve, 244: gas collection pipe, 246: heater, 250: reducing gas source, 270: flare stack

Claims (16)

A gasification power generation device having a gasification device for gasifying an organic matter to produce a dry distillation gas and a carbide, and a power generation device for generating power using the dry distillation gas,
an immersion device for immersing the carbide in a liquid containing a metal salt, and a reducing device for reducing the metal salt on the immersed carbide ,
A system for producing an adsorbent , wherein the gasification power plant is configured to supply a portion of the dry distillation gas to the reduction device . A gasification power generation device having a gasification device for gasifying an organic matter to produce a dry distillation gas and a carbide, and a power generation device for generating power using the dry distillation gas,
an immersion device for immersing the carbide in a liquid containing a metal salt;
a reducing device for reducing the metal salt on the soaked carbide and a drying device for drying the soaked carbide;
A system for producing an adsorbent , wherein the gasification power plant further comprises a first heat exchanger configured to supply thermal energy of the dry distillation gas to the drying device. 3. The system of claim 2 , wherein said first heat exchanger is further configured to supply said thermal energy to said reducer. A gasification power generation device having a gasification device for gasifying an organic matter to produce a dry distillation gas and a carbide, and a power generation device for generating power using the dry distillation gas,
an immersion device for immersing the carbide in a liquid containing a metal salt;
a reducing device for reducing the metal salt on the soaked carbide and a drying device for drying the soaked carbide;
The gasification power plant has a gas engine and a second heat exchanger,
The system for producing adsorbents , wherein the second heat exchanger is configured to supply thermal energy produced by the gas engine to the drying device. A gasification power generation device having a gasification device for gasifying an organic matter to produce a dry distillation gas and a carbide, and a power generation device for generating power using the dry distillation gas,
An immersion device for immersing said carbide in a liquid containing a metal salt, and
a reduction device for reducing the metal salt on the immersed carbide;
A system for producing an adsorbent , wherein the reduction device is configured to supply a portion of the supplied dry distillation gas to the gasification power generation device. 3. The system of claim 1 , further comprising a reducing gas source for supplying reducing gas to the reducer. gasifying organic matter to produce dry distillation gas and char;
immersing the carbide in a liquid containing a metal salt to support the metal salt on the carbide;
generating electricity using the dry distillation gas;
A method for producing an adsorbent, comprising reducing the supported metal salt with a reduction device using a portion of the dry distillation gas. 8. The method of claim 7 , wherein the reduction is performed by supplying a portion of the dry distillation gas to the reduction device. further comprising drying the carbide on which the metal salt is supported using a drying device;
8. The method according to claim 7 , wherein said drying is performed by supplying thermal energy of said dry distillation gas to said drying device. 10. The method of claim 9 , further comprising supplying said heat energy of said carbonized gas to said reducer. further comprising drying the carbide on which the metal salt is supported using a drying device;
8. The method of claim 7 , further comprising supplying thermal energy generated by said power generation to said drying device. 8. The method of claim 7 , wherein said reduction is performed by additionally supplying a reducing gas to said reduction device. 8. The method of claim 7 , further comprising generating electricity using a portion of the dry distillation gas supplied to the reducer. 8. The method of claim 7 , wherein said metal salt is an iron salt. 8. The method of claim 7 , further comprising concentrating the liquid. 16. The method of claim 15 , wherein said concentrating is performed by supplying thermal energy of said carbonized gas to said liquid.

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