JP4457728B2 - Gasification method for contained materials - Google Patents

Description

The present invention relates to a method for gasifying a contained material, and more particularly, to a method for thermochemical gasification of a material containing an organic material.
More specifically, the present invention relates to a gasification method for a contained material having a step of removing tar generated simultaneously with the gasification of the contained material.
In this case, the content of organic substances includes forests, agricultural products, seaweeds, seafood, etc., and organic organic resources (biomass) consisting of organic wastes after using them, or biomass and the rest are general wastes. , Industrial waste, coal, solid fuel such as RDF / RPF, liquid fuel such as kerosene / heavy oil, or a mixture with gas fuel such as natural gas.

Conventionally, as materials containing organic substances, biomass such as forests, agricultural products, seaweeds, seafood, etc., and organic organic resources derived from organic waste after using them are used as energy and industrial raw materials. Development of biomass conversion technology for conversion is progressing.
Recently, a method of gasifying biomass to produce a gas fuel containing carbon monoxide or hydrogen and a method of producing a liquid fuel such as methanol or dimethyl ether have been proposed (see Patent Document 1).

When biomass is thermochemically decomposed and gasified in a reactor, generally a mixed gas containing H ₂ , CO, CO _2, etc. and a tar content (that is, a solid or liquid containing carbon as a main component), etc. Generated.
Usually, in biomass gasification, air, oxygen, water vapor, and combinations thereof are used as gasifying agents.
For example, in the thermochemical decomposition of biomass when steam is used as a gasifying agent, it is considered that biomass (CxHyOz) is decomposed into H ₂ , CO, etc. mainly by the following four chemical reactions (for example, patents) Reference 2).

CxHyOz → (x−z) C + zCO + (y / 2) H ₂ (1)
C + H ₂ O → H ₂ + CO (2)
CO + H ₂ O → CO ₂ + H ₂ (3)
C + CO ₂ → 2CO (4)

Thus, the biomass (CxHyOz) itself is first pyrolyzed to produce H ₂ and CO [Equation (1)], and the tar content (denoted as C), which is a decomposition product, reacts with water vapor (H ₂ O). Further, H ₂ , CO, and CO ₂ are generated [formula (2) and formula (3)], and carbon dioxide (CO ₂ ) generated by the reaction of formula (3) is generated by the reaction of formula (1). It reacts with the produced C to further generate CO [formula (4)].
Incidentally, although the reaction of formula (3) is an equilibrium reaction, a large amount of H ₂ O is present under the above conditions, and CO ₂ is reduced to CO by the reaction of formula (4). move on.

In addition, when other gasifying agents are used, a mixed gas containing H ₂ , CO, CO _{2 and the} like, tar content, and the like are obtained by thermochemical decomposition of biomass.
H ₂ gas fuel can be synthesized directly by gasification of biomass, and liquid fuel such as dimethyl ether and methanol can be synthesized from the H ₂ and CO mixed gas produced from biomass by the following chemical reaction using a catalyst. Can do.

3H ₂ + 3CO → CH ₃ OCH ₃ + CO ₂ (5)
2H ₂ + CO → CH ₃ OH (6)

However, in the gasification with steam, the reactions of the above formulas (2) and (3) proceed, but generally, in the thermochemical decomposition of biomass, a relatively large amount of tar is generated by the reaction of formula (1), This tar content moves in the apparatus in a state where it is contained in a mixed gas such as H ₂ and CO, and adheres to the inside of various apparatuses, and is likely to cause deterioration of the function of the apparatus and clogging. Cause problems.

For the gasification of biomass, a method of thermochemically decomposing biomass using heat generated and generated by combustion of natural gas (for example, methane gas) and CO ₂ has been proposed (for example, see Patent Document 2). In this method, since CO ₂ is present during the thermochemical decomposition of biomass, the reaction of the above formula (4) is promoted, and it is expected that the amount of C in the formula, that is, mainly the tar content is reduced. In practice, however, even with this method, it cannot be said that the amount of tar generated is sufficiently reduced.

Further, methods for directly removing a tar content contained in various gases have been studied (see Non-Patent Documents 1 and 2, for example).
For example, a method of directly removing a tar content contained in a gas by water cooling or adsorption at a low temperature of 403 K (130 ° C.) or less, or a method of removing a tar using a catalyst at a high temperature of 873 to 1173 K (for example, Non-patent documents 3, 4 and 5).
However, if the tar removal method at a low temperature of 403K or less is used, it is not only necessary to cool the mixed gas produced by gasifying biomass, but also effective for synthesizing effective gas components and liquid fuel as gas fuel. There is a disadvantage that even a gas component is absorbed and removed.

Furthermore, when the tar removal method using water is adopted, the installation area becomes large due to the large load of wastewater treatment, and the equipment cost increases.
Moreover, the burden required for maintenance and management of facilities is large, which is a big problem in practice.
Because of this, it is not suitable for the tar removal method that is generated during biomass gasification.
Further, the method of using a catalyst at a high temperature later requires that the mixed gas produced by biomass gasification must be processed at a high temperature, and the reaction of the above formula (3) proceeds, so that the latter stage gas or liquid fuel synthesis the desired CO to process ends up converted to CO _2.

JP 7-41767 A Japanese Patent Laid-Open No. 10-259384 Hasler, P., and Nussbaumer, T., Biomass Biomass Bioenergy, 16, 385 (1999) Devi, L., Ptasinski, K.J., and Janssen, F.J.J.G., Biomass Bioenergy, 24, 125 (2003) Arauzo, J., Radlein, D., Piskorz, J., and Scott, D.S., Ind. Eng. Chem. Res., 36, 67 (1997) Garcia, L., Salvador, M.L., Arauzo, J., and Biobao, R., J. Anal. Appl. Pyrolysis, 58-59, 491 (2001) Myren, C., Hornell, C., Bjornbom, E., and Sjostrom, K., Biomass Bioenergy, 23, 217 (2002)

In order to effectively produce gas fuels such as hydrogen and carbon monoxide by gasifying biomass and to effectively produce liquid fuels such as methanol and dimethyl ether, the effective gas components generated by gasification are wasted. It is important to remove tars that are easily used, and that are generated during the gasification of biomass and adhere to the inside of various production apparatuses, which tend to cause deterioration of the function of the apparatus itself and clogging.
Of the above two methods for removing tar, the method of removing directly by water cooling or adsorption at a low temperature may be effective in terms of tar removal, but it is a mixed gas that becomes a gas fuel generated by biomass gasification. Components and mixed gas components effective for liquid fuel synthesis are also adsorbed and removed.

In addition, as described above, the wastewater treatment load is large, which is not preferable in terms of equipment cost, installation area, equipment maintenance, and the like.
Moreover, since the latter method must be processed at high temperature, it is not preferable for the same reason.
In particular, when a gas mixture produced by gasification is used for liquid fuel synthesis, it is not an effective tar removal method in that it is difficult to obtain a gas composition preferable for liquid fuel production.

Therefore, in order to gasify biomass and effectively convert it to gas fuel or liquid fuel, it is possible to reduce the effective mixed gas components generated by gasification of biomass, and to have a compact facility and It is desired that the operation cost can be reduced and the tar can be easily and effectively removed.
In particular, in a so-called gasification-liquid fuel synthesis system in which biomass is once gasified and liquid fuel is synthesized, the gas generated by biomass gasification is directly used as gas fuel or liquid fuel synthesis for effective use of heat. It is desirable to remove tar effectively and easily to maintain and maintain in a certain temperature range so that it can be used.

For this purpose, the mixed gas component produced from biomass is reacted in a specific temperature range, and the mixed gas component used for synthesis of gas fuel or liquid fuel is effectively reduced without being reduced by adsorption or absorption. It is preferred to use a tar remover that can remove only the.
If it is possible to remove only the tar without affecting the mixed gas component, it is preferable from the viewpoint of effective use of organic waste, improvement of functionality of the apparatus, and manufacturing cost.

The present invention has been made in order to overcome the above-mentioned problems against the background of such a situation.
That is, an object of the present invention is to provide a method of effectively removing tar without reducing the effective mixed gas component generated by biomass gasification.

  Thus, as a result of intensive research on the background of such problems, the present inventors have determined that a mixed gas containing tar produced by gasification of a substance containing an organic substance has a specific specific surface area and an average fine particle size. It has been found that if the mixed gas is processed using a specific carbonaceous substance having a pore size, only tar can be effectively removed in a specific temperature range (283 to 973 K, preferably 423 to 773 K). The present invention has been completed based on knowledge.

That is, the present invention is (1) a method of thermochemically decomposing a substance containing an organic substance to gasify it into hydrogen and carbon monoxide, wherein the hydrogen and carbon monoxide produced by gasification tar contained in the mixed gas, have a tar removal step to remove with a carbonaceous material, consists in gasification of containing machine-based material temperature of the carbonaceous material is 423～773K.

(2) The gas of the inclusion system material according to (1), wherein the carbonaceous material used in the tar removal step has a specific surface area of 250 m ² / g or more and an average pore diameter of 0.1 nm or more. Lies in the chemical law.

In addition, ( 3 ), the carbonaceous material used in the tar removal step resides in the gasification method for an inclusion system material described in (1) above, which is activated carbon.

As long as this invention meets this purpose, it is naturally possible to employ a configuration in which two or more selected from the above 1 to 3 are combined.

  The carbonaceous material referred to in the present invention is a material mainly containing carbon having a tar removing function, such as coke, activated coke, coal, activated carbon, charcoal, graphite (graphite), graphite, fullerene, carbon black, carbon. There are nanotubes.

  According to the gasification method of the inclusion system material of the present invention, since the tar removal step for removing the tar contained in the mixed gas of hydrogen and carbon monoxide generated by gasification using the carbonaceous material is provided. Tar can be effectively removed in the temperature range of at least 283 to 973K without reducing the effective mixed gas component generated by gasification of biomass, which is an organic material.

  Hereinafter, a preferred embodiment of a method for removing tar contained in a mixed gas generated from biomass which is an organic material of the present invention will be described based on the drawings.

[Description of Tar Removal Method Generated from Biomass and Included in Mixed Gas (First Embodiment)]
FIG. 1 is a flowchart showing a method of producing gas fuel by thermochemical gasification from biomass.
FIG. 2 is a schematic diagram for explaining a method for removing tar contained in a mixed gas generated from biomass of the present invention in a method of producing gas fuel by thermochemical gasification from biomass.
In the case of gas fuel production, if tar removal is possible, it is easy to operate and maintain using gas fuel and energy conversion equipment such as gas engines, gas turbines, boilers, steam turbines, or fuel cells. There is little load and it becomes possible to switch to electric power.

As shown in FIG. 1, in this 1st Embodiment, it has a biomass gasification process A, a tar removal process B, and a cooling process, and a reactive gas is stored.
Hereinafter, these steps will be described in detail with reference to FIG.
In the biomass gasification step A shown in FIG. 2, biomass is supplied to a gasification furnace together with water vapor and heated, and thermally decomposed by a chemical reaction such as the above-described formulas (1) to (4), etc. Make it.
More specifically, for example, solid (for example, wood powder) biomass is supplied from the supply means 1 to the gasifier 2.

At that time, if the biomass is supplied to the gasification furnace 2 with excess air mixed therein, oxygen in the air is transported to the gas collecting bag, and then dimethyl ether is synthesized using this to synthesize dimethyl ether or the like. There is a possibility that copper (Cu) in the synthesis catalyst may be oxidized to deactivate the catalyst.
In order to avoid this, in the supply means 1 of the biomass gasification step A, air is used as a non-reactive carrier gas (here, nitrogen N ₂ ) so that the carbon contained in the biomass is incompletely combusted. It is preferable to dilute and carry biomass or a H ₂ · CO mixed gas generated from biomass into the carrier gas.

As the gasification furnace 2, for example, a fixed bed type is used.
The gasification furnace 2 has a configuration in which a quartz tube 3 is surrounded by an electric furnace 4.
In order to prevent the biomass from being lowered in the quartz tube 3 before it is gasified, the inside of the quartz tube 3 of the gasification furnace 2 has a plate 5 (that is, a tray-shaped one having a plurality of eyes). ) Is disposed, and ceramic balls 6 are laminated thereon.

When the biomass is supplied from the supply means 1, it is deposited on the ceramic balls 6.
And when water vapor | steam is supplied there, chemical reactions, such as Formula (1)-Formula (4) mentioned above, will occur, and biomass will be decomposed | disassembled thermochemically.
At that time, if the temperature of the gasification furnace 2 is kept at 773 to 1273 K, the biomass and water vapor are heated to this temperature range.

If it is this temperature range, reaction of the said Formula (1)-Formula (4) will advance efficiently from a viewpoint of reaction efficiency.
The temperature of the gasification furnace 2 is temperature-controlled through, for example, a thermocouple 7.
The reaction between biomass and water vapor proceeds favorably in the above temperature range, and the biomass is decomposed thermochemically and completely gasified.

A gas containing H ₂ and CO generated by thermochemical decomposition of biomass, that is, a mixed gas of H ₂ and CO, passes through the gaps of the ceramic balls 6 and passes through the eyes of the eye plate 5 to lower tar removal step B Move to.
At that time, the H ₂ · CO mixed gas contains a gaseous (ie, vaporized) tar content.
The tar removal step B is a step unique to the present invention, and the carbonaceous material 8 adsorbs the gaseous tar content contained in the H ₂ · CO mixed gas generated in the biomass gasification step A. Furthermore, the tar content adsorbed on the surface of the carbonaceous material can be modified to H ₂ and CO with water vapor.

Particularly limited, the mixed gas produced in the biomass gasification step A has a specific surface area of 250 m ² / g or more and an average pore diameter of 0.1 nm or more, preferably from 283 to 973 K, preferably from 423 to 773 K. By passing through a layer of carbonaceous material 8 kept in the temperature range, only the tar contained in the mixed gas produced from the biomass is effectively removed, and a purified gas fuel containing no tar is produced. can do.
In order to remove tar effectively, more preferably, the specific surface area of the carbonaceous material 8 is 800 m ² / g or more and the average pore diameter is 0.5 nm or more.

In the configuration example shown in FIG. 2, the tar removal step B is formed in a state continuous with the biomass gasification step A.
That is, the quartz tube 3 of the gasification furnace 2 is extended downward as it is, is surrounded by the electric furnace 4, and the eye plate 5 is disposed inside the quartz tube 3.
And the carbonaceous material 8 is laminated | stacked on the upper part of this eye plate 5, The removal of a tar part is performed by this carbonaceous material.
As the carbonaceous material 8, for example, activated carbon is preferably used.
In particular, good results can be obtained when the specific surface area of the carbonaceous material 8 is 250 m ² / g or more and the average pore diameter is 0.1 nm or more.

The carbonaceous material 8 adsorbs the gaseous tar content contained in the H ₂ · CO mixed gas that has been carried from the biomass gasification step A by the carrier gas.
In addition, the shape of the carbonaceous material 8 used for tar removal of the present invention may be powder, granular, pellet, plate, honeycomb, or the like, or may be held on a carrier of another material. .
When the tar removal characteristic of the carbonaceous material 8 is deteriorated, a conventional activation method such as steam treatment or heat treatment can be used.
And the water vapor carried from the biomass gasification step A attacks the carbon (C) in the tar content adsorbed on the surface of the carbonaceous material, thereby causing the chemical reaction of the above-described formula (2), H ₂ and CO are newly generated.

At that time, if the inside of the furnace of the tar removal step B including the carbonaceous material 8 is heated to a temperature range of 283 to 973 K and the tar content is adsorbed to the carbonaceous material 8 within this temperature range, the tar is efficiently obtained. Can be removed.
Incidentally, the H ₂ and CO produced in the biomass gasification step A pass through the voids of the carbonaceous material 8 with little involvement in the reaction in the tar removal step B.

In this way, biomass is completely gasified in the biomass gasification step A, so that not only H ₂ and CO etc. but also a tar content, that is, a solid containing a high molecular organic compound having a relatively high-order carbon chain as a skeleton The liquid material is also vaporized, so to speak, it is in a state of being separated for each molecule.
And since it adsorb | sucks with the carbonaceous substance 8 and reacts with water vapor | steam, the carbon in a tar part becomes easy to receive the attack of water vapor | steam, and tar can be removed efficiently.

Therefore, according to the present invention, it is not necessary to newly add natural gas or the like as in the prior art, and the tar content that is a by-product generated from biomass, which is unnecessary, is effectively improved by further reforming. It can be used for.
In addition, by modifying the tar content to H ₂ , CO, or the like in this way, the tar content can be reduced, and the problem of clogging due to adhesion to various devices will also be solved.
As described above, the mixed gas that has passed through the tar removal step B flows into the water cooler 9.

The H ₂ / CO mixed gas is cooled by the water cooler 9, and at the same time, tar remaining in the mixed gas is liquefied and adhered to the wall surface of the glass bottle and removed.
When the composition of the H ₂ · CO mixed gas from which tar content and the like are removed in this way is detected, N ₂ , CO ₂ , and CH _{4 as} carrier gases in addition to H ₂ and CO are detected. The following hydrocarbons and organic compounds were not detected.

N ₂ , CO ₂ , and CH ₄ , for example, later synthesize dimethyl ether do not affect the reaction at all and do not affect the carbonaceous material 8, and do not deteriorate or deactivate the carbonaceous material 8. There is no problem even if it is contained in the H ₂ · CO mixed gas.
The mixed gas that has passed through the water cooler 9 is measured in volume by a volume meter 10 and stored in a storage tank 11.
In the storage tank 11, for example, when dimethyl ether is synthesized in a later step, the production rate of the H ₂ · CO mixed gas in the biomass gasification step A is higher than the synthesis rate of dimethyl ether (that is, the consumption rate of the H ₂ · CO mixed gas). When it is too large, it serves as a buffer for temporarily storing the H ₂ · CO mixed gas.

[Description of Tar Removal Method Generated from Biomass and Included in Mixed Gas (Second Embodiment)]
FIG. 3 is a flowchart showing a method for producing liquid fuel by thermochemical liquefaction from biomass.
FIG. 4 shows a method for synthesizing a liquid fuel by thermochemical gasification from biomass and using the produced mixed gas (liquid fuel synthesizing step), and the tar contained in the mixed gas produced from the biomass of the present invention. It is a schematic diagram for demonstrating a removal method intelligibly.

As shown in FIG. 3, the second embodiment includes a biomass gasification step A, a tar removal step B, and a liquid fuel synthesis step C, and dimethyl ether is generated.
Here, the biomass gasification step A and the tar removal step B are the same as the steps shown in FIG.

Then, as shown in FIG. 4, the mixed gas that has undergone the tar removal step B is pressurized by the booster 12 and sent to the reaction furnace 13 that executes the liquid fuel synthesis step C.
Similar to the gasification furnace 2 in the biomass gasification step A, the reaction furnace 13 has a configuration in which the quartz tube 3 is surrounded by an electric furnace 4, and a dimethyl ether synthesis catalyst 14 having a size of 1 mm is packed inside the reaction furnace 13. .
As the dimethyl ether synthesis catalyst 14, for example, a Cu / ZnO catalyst, a Cu / Cr ₂ O ₃ / ZnO catalyst or the like mixed with γ-alumina or zeolite is preferably used.

It is preferable from the viewpoint of the reaction efficiency of dimethyl ether if the H ₂ · CO mixed gas is pressurized to 1 to 10 MPa and reacted in a temperature range of 423 to 673 K.
Under these conditions, the chemical reaction of equation (5) previously described on dimethylether synthesis catalyst 14 proceeds effectively, since H ₂ and CO in the H 2 _· CO mixed gas is synthesized efficiently dimethyl ether is there.
Synthesized dimethyl ether is a gas at normal temperature, but its boiling point is as high as 248.7K compared to N ₂ , CO ₂ , CH ₄ (or remaining H ₂ or CO) in the H ₂ · CO mixed gas, It can be easily separated by cooling.

  Further, in a liquid fuel synthesizing process of methanol, dimethyl ether or the like by the refined mixed gas after tar removal, when liquid fuel is synthesized in a temperature range of 423 to 773 K using a synthesis catalyst such as methanol or dimethyl ether, the liquid is converted from biomass. A significant improvement in the thermal efficiency of the fuel production system is expected.

In 1st and 2nd embodiment mentioned above, it adheres to various apparatuses by the gasification method of biomass which has the tar removal process which removes the tar content contained in the mixed gas produced | generated by gasification of biomass effectively. Thus, the problem of clogging and the like can be solved.
In addition, effective mixed gas components gasified from biomass can be used for gas fuel or liquid fuel production without wasting, and effective use of not only biomass but also organic waste, biomass gasification- It is also preferable from the viewpoint of functionality and manufacturing cost of a gas fuel production apparatus and an integrated system of biomass gasification and liquid fuel synthesis.

The present invention has been described above. However, the present invention is not limited to the embodiments, and it is needless to say that various other modifications can be made without departing from the essence of the present invention.
For example, the experimental apparatus shown in FIGS. 2 and 4 is shown to explain the biomass gasification and gas fuel production and liquid fuel production method of the present invention. As long as they are the same, it is possible to adopt other forms as long as they are the same in principle.

In fact, the tar removal method used in the present invention is a gasification furnace in which a substance containing an organic substance is decomposed thermochemically or gasified using a gasifying agent containing oxygen, air, or steam as required. Removes tar contained in product gas when processing in gasification melting furnace, pyrolysis furnace, carbonization furnace, carbonization furnace, gasification reforming furnace, incinerator, and equipment such as boilers and other combustion equipment Can also be used.
Further, at the stage of practical use, the tar removal method or the shape of the apparatus needs to be scaled up and the form changed accordingly.
Various forms such as a fixed bed, a moving bed, a fluidized bed, a cylindrical drum, a spouted bed, an air current transport, or a combination thereof can be considered as a form of the tar removing device, but it is not particularly limited thereto.

Tar removal section using various carbonaceous materials using a gasification unit made of quartz comprising a biomass gasification section and a tar removal section having the atmospheric pressure downdraft gasification furnace shown in FIGS. The tar removal characteristics were evaluated at each temperature.
The raw material biomass was supplied by a screw feeder, and air was used as a gasifying agent.
The gasifier was heated from the outside by an electric furnace.
The length of the quartz reaction tube was 730 mm and the inner diameter was 21 mm.

A carbonaceous material having a thickness of 20 mm was installed in the tar removal part (removal part temperature 473 to 773 K), and the tar removal characteristics were evaluated with a certain volume of carbonaceous material.
The gas from the gasifier was cooled with water and 253K, and then passed through a wet gas meter (W-NK-0.5; Shinagawa) and collected in a gas collection bag and analyzed.
As the biomass, macamba (250-500 um) dried at 378 K for 24 hours was used.
N ₂ gas was used as the carrier gas.

In the biomass gasification step, carbon-based raw material speed: about 5.0 × 10 ⁻³ C-mol · min ⁻¹ , air ratio ([O ₂ ] / [C]): 0.3 Then, biomass and air were supplied, and a gasification operation was performed at 1173 K for 60 minutes under atmospheric pressure.
The gas produced by the gasification of biomass was analyzed using a gas chromatograph TCD (GC-8A; Shimazu, Molecular Sieve 5A, Polapack Q) and FID (GC353B; GL Science, Squalane).
The gasification rate based on carbon was 79.5 C-mol%.

Tar was defined as a substance other than gas.
The weight of the carbonaceous material layer before and after the reaction was measured and used as the tar amount from which the increment was removed.
Tar removal rate was defined as the ratio of the amount of tar removed to the amount of tar.

Examples will be described below.
Needless to say, the present invention is not limited to these examples.
[Example 1]
In the biomass gasifier shown in FIGS. 2 and 4, the tar removal temperature 673K is obtained by using activated carbon AC-1 (1-2 mm) having a specific surface area of 1150 m ² / g and an average pore diameter of 0.61 nm as the carbonaceous material. The tar removal characteristics were evaluated.

[Example 2]
In the same manner as in Example 1, activated carbon AC-2 (1 to 2 mm) having a specific surface area of 490 m ² / g and an average pore diameter of 0.97 nm was used as the carbonaceous material, and the tar removal characteristics were obtained at a tar removal part temperature of 673K. evaluated.

Example 3
In the same manner as in Example 1, using a activated carbon AC-3 (1-2 mm) having a specific surface area of 1120 m ² / g and an average pore diameter of 1.7 nm as the carbonaceous material, the tar removal characteristics at a tar removal temperature of 673K evaluated.

Example 4
Using the same specific surface area 1120 m ² / g as in Example 3 and activated carbon AC-3 (1 to 2 mm) having an average pore diameter of 1.7 nm as the carbonaceous material, the tar removal part temperature of 973 K is the same as in Example 1. The tar removal characteristics were evaluated.

Example 5
Using the same specific surface area 1120 m ² / g as in Example 3 and activated carbon AC-3 (1 to 2 mm) having an average pore diameter of 1.7 nm as the carbonaceous material, the tar removal part temperature 573 K is the same as in Example 1. The tar removal characteristics were evaluated.

Example 6
Using the same specific surface area 1120 m ² / g as that of Example 3 and activated carbon AC-3 (1 to 2 mm) having an average pore diameter of 1.7 nm as the carbonaceous material, the tar removal part temperature 473K is the same as in Example 1. The tar removal characteristics were evaluated.

Example 7
In the same manner as in Example 1, activated carbon AC-3 (1 to 2 mm) having a specific surface area of 250 m ² / g and an average pore diameter of 1.7 nm was used as the carbonaceous material, and the tar removal characteristics were obtained at a tar removal part temperature of 283K. evaluated.

Example 8
Tar removal part temperature 673K in the same manner as in Example 1 using charcoal (1 to 2 mm) with a specific surface area of 250 m ² / g and an average pore diameter of 0.4 nm, which is a carbonaceous material and gas-activated with water vapor at 1073 K. The tar removal characteristics were evaluated.

[Comparative Example 1]
In order to remove tar, alumina balls (1 to 2 mm) having a specific surface area of 10 m ² / g and an average pore diameter of 0.5 nm, which are non-carbon substances, are used in the same manner as in Example 1 instead of carbonaceous substances. The tar removal characteristics were evaluated at a tar removal temperature of 673K.

〔result〕
In each Example, the reduction | decrease of the gas component produced | generated by gasification of biomass was not seen by passing a tar removal part.
The removal rate of the generated tar at the tar removal portion was as follows.
Example 1 32.4%
Example 2 ... 15.0%
Example 3 52.6%
Example 4 ... 15.0%
Example 5: 100.0%
Example 6: 89.6%
Example 7 20.0%
Example 8 ... 10.6%
Comparative example 5.6%
In addition, in FIG. 5, the tar removal conditions and evaluation by a carbonaceous substance were compared and shown collectively.

[Evaluation]
From the result of an Example, it has shown that the activated carbon used for this invention is effective in tar removal also in the temperature range of 283-973K.
In addition, from the comparison of Example 1, Example 2, and Example 3, if the same volume is used, the tar removal characteristics of the activated carbon are increased, the larger the specific surface area, the larger the average pore diameter, the higher the tar removal characteristics. Is clearly shown.

Moreover, from the comparison of Example 3, Example 4, Example 5, and Example 6 and Example 7, if the same activated carbon is used, the maximum tar removal characteristic is exhibited at 573K.
Also, it is shown that if activated carbon having a large specific surface area and a large average pore diameter is used, a sufficiently high tar removal characteristic can be obtained even at 973K. However, when alumina balls are used, an effective tar removal characteristic at 673K is It clearly shows that it cannot be obtained.

  The present invention relates to a gasification method of an organic material, that is, a gasification method of a contained material having a step of removing tar generated simultaneously with the gasification of the contained material. As long as it can be utilized, it can be applied to other fields, for example, the field of waste treatment, etc., and its field of use is wide-ranging.

FIG. 1 is a flowchart showing a method of producing gas fuel by thermochemical gasification from biomass. FIG. 2 is a schematic diagram for easily explaining the method for removing tar contained in the mixed gas produced from the biomass of the present invention. FIG. 3 is a flowchart showing a method for producing liquid fuel by thermochemical liquefaction from biomass. FIG. 4 shows a method for synthesizing a liquid fuel by a thermochemical gas from biomass and synthesizing a liquid fuel (liquid fuel synthesizing step) from the biomass. It is a schematic diagram for demonstrating a removal method clearly. FIG. 5 is a comparative view collectively showing the tar removal conditions and evaluation by the carbonaceous material.

Explanation of symbols

A ... Biomass gasification process B ... Tar removal process C ... Liquid fuel synthesis process 1 ... Supply means 2 ... Gasification furnace 3 ... Quartz tube 4 ... Electric furnace 5 ... Glass plate 6 ... Ceramic ball 7 ... Thermocouple 8 ... Carbonaceous Substance 9 ... Water cooler 10 ... Volume meter 11 ... Storage tank 12 ... Booster 13 ... Reactor 14 ... Dimethyl ether synthesis catalyst

Claims (3)

A method of thermochemically decomposing a substance containing an organic substance to gasify it into hydrogen and carbon monoxide,
A tar removal step for removing tar contained in a gas mixture of hydrogen and carbon monoxide generated by gasification using a carbonaceous material;
A gasification method for an inclusion type material, wherein the temperature of the carbonaceous material is 423 to 773K. ^2. The gasification method for an inclusion-based material according to claim 1, wherein the carbonaceous material used in the tar removal step has a specific surface area of 250 m ² / g or more and an average pore diameter of 0.1 nm or more. .   2. The gasification method for an inclusion-based material according to claim 1, wherein the carbonaceous material used in the tar removal step is activated carbon.

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