JP2015105238A - Apparatus and method for producing chemical product - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an apparatus and a method for producing a chemical product, in each of which the production efficiency of the chemical product can be improved.SOLUTION: An apparatus 1 for producing the chemical product includes: a gasification part 11 for generating synthesis gas containing carbon monoxide from a carbon source; a hydrogen gas generation part 18 for generating hydrogen gas by decomposing water; and a catalytic reaction part 16 for synthesizing the chemical product by a catalytic reaction by using the generated synthesis gas and the generated hydrogen gas. It is preferable that water is decomposed by a thermochemical decomposition reaction to generate the hydrogen gas in the hydrogen gas generation part 18.

Description

  The present invention relates to an apparatus and a method for producing a chemical product.

  Conventionally, a method of producing bioethanol by chemically reacting a synthesis gas (a mixed gas of carbon monoxide and hydrogen) obtained by gasifying biomass using a catalyst is known (for example, Patent Document 1). reference).

JP 2013-213089 A

  There is a desire to further improve the production efficiency of alcohol such as bioethanol.

  A main object of the present invention is to provide a chemical production apparatus and a chemical production method capable of improving the production efficiency of a chemical such as alcohol.

  The chemical product manufacturing apparatus according to the present invention includes a gasification section, a hydrogen gas generation section, and a catalytic reaction section. The gasification unit generates synthesis gas from a carbon source. The hydrogen gas generator generates hydrogen gas by decomposing water. The catalytic reaction unit synthesizes a chemical by catalytic reaction using synthesis gas and hydrogen gas.

  The hydrogen gas generation unit preferably generates hydrogen gas by decomposing water by a thermochemical decomposition reaction.

  The hydrogen gas generator preferably decomposes water using heat released from the gasifier.

  The chemical product manufacturing apparatus may further include a measurement unit and an adjustment unit. The measuring unit measures the composition ratio of carbon monoxide and hydrogen in the synthesis gas supplied to the catalytic reaction unit. An adjustment part adjusts the usage-amount with respect to synthesis gas of the hydrogen gas generated from a hydrogen gas generation part based on the composition ratio of carbon monoxide and hydrogen measured by the measurement part.

  The chemical product may be at least one selected from the group consisting of alcohol, aldehyde, and sulfonic acid.

  The chemical may be ethanol.

  The ratio of hydrogen to carbon monoxide (hydrogen / carbon monoxide) contained in the synthesis gas generated in the gasification section may be less than 2.

  The chemical product manufacturing method according to the present invention includes a step of obtaining a synthesis gas, a step of generating hydrogen gas, and a step of synthesizing the chemical product. In the step of obtaining the synthesis gas, the synthesis gas is obtained from a carbon source. In the step of generating hydrogen gas, water is decomposed to generate hydrogen gas. In the step of synthesizing the chemical product, the chemical product is synthesized by a catalytic reaction using synthesis gas and hydrogen gas.

  In the step of generating hydrogen gas, it is preferable to generate hydrogen gas by decomposing water with thermal energy.

  ADVANTAGE OF THE INVENTION According to this invention, the manufacturing apparatus and manufacturing method which can improve the production efficiency of a chemical can be provided.

It is a block diagram which shows the structure of the alcohol manufacturing apparatus which concerns on 1st Embodiment. It is a block diagram which shows the structure of the alcohol manufacturing apparatus which concerns on 2nd Embodiment. It is a block diagram which shows the structure of the alcohol manufacturing apparatus which concerns on 3rd Embodiment.

  Hereinafter, an example of the preferable form which implemented this invention is demonstrated. However, the following embodiment is merely an example. The present invention is not limited to the following embodiments.

(First embodiment)
FIG. 1 is a block diagram showing a configuration of an alcohol production apparatus 1 according to the first embodiment.

  The alcohol production apparatus 1 is an apparatus that produces alcohol from a carbon source. The alcohol may be at least one of ethanol, methanol, propanol, butanol and the like.

  As shown in FIG. 1, the alcohol production apparatus 1 includes a gasification unit 11, a purification unit 12, a catalyst reaction unit 16, a gas-liquid separation unit 17, and a hydrogen gas generation unit 18.

  The gasification unit 11 generates synthesis gas from a carbon source. By partially oxidizing (incomplete combustion) the carbon source supplied to the gasification unit 11, the gas source 11 is changed to synthesis gas. For example, non-fossil organic resources such as organic waste and biomass can be used as the carbon source. “Syngas” refers to a gas containing carbon monoxide and hydrogen. The synthesis gas may include at least one of carbon dioxide gas, nitrogen gas, oxygen gas, and the like, for example.

  In the present embodiment, an example in which synthesis gas is generated by partially oxidizing a carbon source will be described. However, the present invention is not limited to this. For example, the synthesis gas may be generated by fermentation of microorganisms.

The purification unit 12 purifies the synthesis gas supplied from the gasification unit 11. Purification unit 12 can, for example, can be constituted by the absorption tower 13, the desulfurization unit 14, and the CO ₂ separation section 15.

  The absorption tower 13 is connected to the gasification unit 11. The absorption tower 13 separates and removes the impurities from the synthesis gas by dissolving the impurities in the synthesis gas generated in the gasification unit 11.

  The absorption tower 13 is connected to the desulfurization section 14. The desulfurization unit 14 separates and removes sulfur from the synthesis gas. Impurities and sulfur removed in the absorption tower 13 and the desulfurization section 14 deteriorate the catalyst or lower the purity of the alcohol to be produced. Therefore, it is preferable to remove the impurities and sulfur before reaching the catalyst reaction section 16. .

The desulfurization unit 14 is connected to the CO ₂ separation unit 15. The CO ₂ separation unit 15 separates and removes CO ₂ in the synthesis gas.

  The hydrogen gas generation unit 18 decomposes water to generate hydrogen gas. The hydrogen gas generated in the hydrogen gas generation unit 18 is supplied to the catalyst reaction unit 16.

The hydrogen gas generator 18 may generate hydrogen gas by decomposing water by a thermochemical decomposition reaction, for example. Here, the “thermochemical decomposition reaction” refers to a reaction in which hydrogen is generated from water using a plurality of chemical reactions in which the reaction proceeds at a lower temperature than the temperature required when water is decomposed only by heat. Specific examples of the thermochemical decomposition reaction include a sodium cycle. In the sodium cycle, water is decomposed at 400 ° C. by using three reactions of H ₂ O + Na ₂ O ₂ → 2 NaOH + 1 / 2O ₂ , 2NaOH + 2Na → H ₂ + 2Na ₂ O, 2Na ₂ O → Na ₂ O ₂ + 2Na. Generate hydrogen gas.

  But the hydrogen gas generation part 18 may generate | occur | produce hydrogen gas by methods other than the method using a thermochemical decomposition reaction. The hydrogen gas generator 18 may generate hydrogen gas by electrolyzing, pyrolyzing, or photolyzing water, for example. However, from the viewpoint of reducing energy required for generating hydrogen gas, it is preferable to use a method of generating hydrogen gas by a thermochemical decomposition reaction.

  In the hydrogen gas generator 18, oxygen gas is also generated together with hydrogen gas. The oxygen gas is preferably separated from the hydrogen gas and supplied to the gasification unit 11.

  The hydrogen gas generator 18 preferably decomposes water using heat released from the gasifier 11. In this case, the amount of heat separately applied to the hydrogen gas generator 18 can be reduced. Therefore, the energy required for producing alcohol can be reduced.

  The catalytic reaction unit 16 synthesizes alcohol by a catalytic reaction using the synthesis gas supplied from the purification unit 12 and the hydrogen gas supplied from the hydrogen gas generation unit 18. Examples of the catalyst preferably used for the catalytic reaction include a quaternary catalyst composed of rhodium, manganese, lithium, and magnesium.

  The catalytic reaction unit 16 is connected to the gas-liquid separation unit 17. The gas-liquid separation unit 17 is supplied with a product containing alcohol from the catalyst reaction unit 16. The product to be supplied generally contains water, unreacted synthesis gas and the like in addition to alcohol. The gas-liquid separator 17 separates a liquid component containing alcohol and a gas component containing unreacted synthesis gas. The separated gas component containing unreacted synthesis gas is supplied again to the catalytic reaction unit 16.

  Moreover, the gas-liquid separation part 17 refine | purifies alcohol by distilling the liquid containing alcohol and water.

By the way, it can be considered that alcohol is produced using cellulose-based biomass as a raw material, using synthesis gas mainly composed of carbon monoxide and hydrogen generated by thermochemical conversion in a gasification furnace. However, the molar ratio of carbon monoxide to hydrogen (H ₂ / CO) in this synthesis gas is smaller than the ideal molar ratio of 2 and there is a problem that the hydrogen gas concentration is low. Usually, the molar ratio (H ₂ / CO) of carbon monoxide to hydrogen in this synthesis gas is 1.5 or less, which is about 1.

Therefore, in Patent Document 1, in order to increase the concentration of H _{2 in} the synthesis gas, the synthesis gas is reformed using a CO shift reaction (CO + H ₂ O → CO ₂ + H ₂ ). However, when the CO shift reaction is performed, the carbon monoxide concentration in the synthesis gas decreases. This reduces the amount of alcohol that can be produced from synthesis gas per unit volume.

  In the present embodiment, the hydrogen gas generated by decomposing water in the hydrogen gas generation unit 18 is supplied to the catalyst reaction unit 16, thereby bringing the molar ratio of carbon monoxide and hydrogen close to the ideal molar ratio. ing. Therefore, it is not always necessary to perform a synthesis gas reforming reaction in which the concentration of carbon monoxide in the synthesis gas decreases. Therefore, the production efficiency of alcohol can be improved.

(Second Embodiment)
FIG. 2 is a block diagram showing the configuration of the alcohol production apparatus 1a according to the second embodiment.

  As shown in FIG. 2, the configuration of the alcohol production apparatus 1a according to the second embodiment is different from that of the alcohol production apparatus 1 according to the first embodiment in that the gasification unit 11 and the absorption tower 13 are different. The heat exchanger 21 is provided in the path between. The heat exchanger 21 extracts thermal energy from the synthesis gas generated by the gasification unit 11. The heat energy taken out by the heat exchanger 21 is supplied to the hydrogen gas generator 18 and used for water decomposition. Thereby, the energy which should be supplied to the hydrogen gas supply part 18 from the outside can be reduced. Therefore, the energy required for producing alcohol can be reduced.

(Third embodiment)
FIG. 3 is a block diagram showing a configuration of an alcohol production apparatus 1b according to the third embodiment.

  As shown in FIG. 3, the configuration of the alcohol production device 1 b according to the third embodiment is different from the configuration of the alcohol production device 1 a according to the second embodiment in that a measurement unit 31 and an adjustment unit 32 are provided. It is a point.

  The measuring unit 31 is provided in a path between the heat exchanger 21 and the absorption tower 13. The measuring unit 31 measures the composition ratio of the synthesis gas. Specifically, the measurement unit 31 acquires, for example, at least the concentration of carbon monoxide and the concentration of hydrogen gas in the synthesis gas using a gas chromatograph or the like. The measurement part 31 does not necessarily need to measure the composition ratio of all the compositions contained in the synthesis gas. From the measurement result of the measuring unit 31, the composition ratio of carbon monoxide and hydrogen in the synthesis gas is calculated.

  The adjustment unit 32 is provided in a path between the hydrogen gas generation unit 18 and the catalyst reaction unit 16. The adjustment unit 32 adjusts the usage amount of the hydrogen gas generated from the hydrogen gas generation unit 18 with respect to the synthesis gas based on the composition ratio of carbon monoxide and hydrogen measured by the measurement unit 31. Specifically, the adjustment unit 32 can be configured by a valve or the like.

As described above, the molar ratio of carbon monoxide to hydrogen (H ₂ in the synthesis gas) is increased by increasing the proportion of H _{2 in} the synthesis gas using the hydrogen gas generated in the hydrogen gas generation unit 18. / CO) can be less than 2. However, the ratio of CO and H ₂ may vary depending on the properties of organic waste, biomass, etc. that are subjected to gasification. Even in such a case, the molar ratio (H ₂ / CO) of carbon monoxide and hydrogen in the synthesis gas can be made less than 2 by adjusting the amount of hydrogen gas used by the adjusting unit 32. it can. Therefore, it is possible to stably maintain the optimum H ₂ ratio for ethanol synthesis.

  In the first to third embodiments, examples of producing alcohol as a chemical have been described. However, the present invention is not limited to this. The chemical product is not particularly limited as long as it can be synthesized from synthesis gas. For example, at least one of alcohol, aldehyde, and sulfonic acid may be synthesized from synthesis gas.

1, 1a, 1b: Alcohol production apparatus 11: Gasification unit 12: Purification unit 13: Absorption tower 14: Desulfurization unit 15: CO ₂ separation unit 16: Catalytic reaction unit 17: Gas-liquid separation unit 18: Hydrogen gas generation unit 21 : Heat exchanger 31: Measuring unit 32: Adjustment unit

Claims (9)

A gasification section for generating synthesis gas from a carbon source;
A hydrogen gas generator that decomposes water to generate hydrogen gas;
A catalytic reaction section for synthesizing a chemical by catalytic reaction using the synthesis gas and the hydrogen gas;
Chemical production equipment equipped with.   The chemical product manufacturing apparatus according to claim 1, wherein the hydrogen gas generation unit generates hydrogen gas by decomposing water by a thermochemical decomposition reaction.   The chemical product manufacturing apparatus according to claim 1 or 2, wherein the hydrogen gas generation unit decomposes water using heat released from the gasification unit. A measuring unit for measuring a composition ratio of carbon monoxide and hydrogen in the synthesis gas supplied to the catalytic reaction unit;
An adjustment unit that adjusts the amount of hydrogen gas generated from the hydrogen gas generation unit to the synthesis gas based on the composition ratio of the carbon monoxide and hydrogen measured by the measurement unit;
The chemical production apparatus according to any one of claims 1 to 3, further comprising:   The chemical production apparatus according to any one of claims 1 to 4, wherein a ratio of hydrogen to carbon monoxide (hydrogen / carbon monoxide) contained in the synthesis gas generated in the gasification unit is less than 2.   The chemical product manufacturing apparatus according to any one of claims 1 to 5, wherein the chemical product is at least one selected from the group consisting of alcohol, aldehyde, and sulfonic acid.   The chemical product manufacturing apparatus according to any one of claims 1 to 6, wherein the chemical product is ethanol. Obtaining synthesis gas from a carbon source;
A process of decomposing water to generate hydrogen gas;
Synthesizing a chemical by catalytic reaction using the synthesis gas and the hydrogen gas;
A chemical manufacturing method comprising: The chemical production method according to claim 8, wherein in the step of generating hydrogen gas, water is decomposed by thermal energy to generate hydrogen gas.

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