KR101503607B1 - 2 stage fluidized bed biomass gasifier for hydrogen production and method of preparing hydrogen using the same - Google Patents

Abstract

The present invention relates to a two-stage fluidized bed biomass gasification apparatus and method for producing a high concentration of hydrogen using a kind of biomass resources of sustainable energy resources and making it possible to utilize it as a raw material for electric power, fuel cell, chemical industry .
The two-stage fluidized bed biomass gasification apparatus of the present invention can continuously perform syngas production reaction and water gas conversion reaction in one single reactor, thereby making it possible to produce high-concentration hydrogen while reducing the amount of carbon monoxide to be discharged. Further, the gasification apparatus of the present invention is economical and efficient because it utilizes the gas and energy generated in the synthesis gas generation reaction for the water gas reaction.
The apparatus and method of the present invention can utilize biomass resources having a high water content of 20 wt% or more to produce hydrogen gas at a high concentration without addition of water vapor.

Description

[0001] The present invention relates to a two-stage fluidized bed biomass gasifier for hydrogen production,

The present invention relates to a two-stage fluidized bed biomass gasification apparatus and method for hydrogen production. More specifically, the present invention relates to a two-stage fluidized-bed biomass gasification apparatus and a method of producing the same, which can utilize a kind of biomass resources of sustainable energy resources to produce hydrogen at a high concentration and utilize it as a raw material for power, fuel cell, ≪ / RTI >

Concerns about sustainable energy systems caused by environmental problems such as global warming and the risk of depletion of fossil fuels such as coal, oil, and natural gas that are used as main energy resources, And the expansion of domestic energy resources has become a key issue. Therefore, biomass, which can be supplied sustainably in Korea, is recognized as an important energy resource.

Since biomass resources are recognized as carbon-neutral resources, they can contribute significantly to reducing carbon dioxide emissions in Korea. Accordingly, various thermochemical conversion processes utilizing biomass resources have been developed. The biomass energy conversion process currently being developed is very diverse, including fixed bed, fluidized bed, and circulating fluidized bed. However, the high water content of biomass resources deteriorates the economics of the biomass energy conversion process and the use of low moisture biomass resources Economies of scale are difficult to achieve.

The fluidized bed gasification system is a device in which a solid layer floats due to a reaction gas having an upward flow and flows like a gas and a liquid, and gas-solid or solid-solid is mixed very quickly to cause a gasification reaction. And gas-solid contact through the complete mixing of the oxidizing agent, so that the reaction rate is fast and the efficiency can be increased. It is also characterized in that a relatively wide range of fuels can be used, the reaction is rapid at low temperatures, and the ash is treated dry to reduce heat loss due to ash slag discharge. Generally, fluidized bed gasification systems have been used in energy conversion processes and energy recovery processes related to gasification of coal, sludge or waste polymers, waste wood and waste tires in various chemical processing fields such as alternative energy development and waste treatment, Extensive research and development is underway.

In addition, the fluidized bed gasifier has superior heat transfer characteristics compared to other types of gasification reactors, and the yield and composition of the gasification product gas are constant due to the uniform temperature distribution in the reactor, the residence time of the solid reactants in the reactor is relatively long , And the solid has the same flow as the fluid, so that the solid treatment is easy. Thus, the fluidized bed gasification apparatus has been studied and developed in various ways in order to increase the heat quantity and increase the yield, because the main purpose is to obtain a high-quality synthesis gas and a high-temperature combustion gas produced by processing the solid.

In the existing biomass gasification processes registered as patents, syngas waste is injected into a gasifier operated at a temperature of 500-900 to produce syngas using oxygen or steam as a gasifier Korean Patent No. 0659497). Conventional biomass gasification processes consist of a gasification reactor, a purifier (composed of tar, grass recovery, scrubber, etc.), and a gasifier injection (Korean Patent No. 0742159). In addition, an additional tar removal system was installed in the biomass gasification process to improve the efficiency (Korean Patent No. 10-2009-0129730). In addition, a gasification facility using supercritical water has also been developed using microalgae composed mostly of water (Korean Patent No. 10-1142818).

However, most of the biomass gasification processes developed so far require the use of low-moisture biomass resources or excessive process and operating costs, such as supercritical conditions. Also, since the content of carbon monoxide in the syngas is very high, it is not suitable for a process requiring a high concentration of hydrogen such as a fuel cell.

The present invention provides an apparatus and a method for producing hydrogen at a high concentration using biomass resources having a high water content of 20 wt% or more as a raw material.

The present invention provides an apparatus and method for efficiently linking a synthesis gas production reaction with a water gas shift reaction for converting carbon monoxide present in the produced synthesis gas into hydrogen, which is a superconversion energy.

One aspect of the present invention is

A reactor body of a columnar structure;

An air or oxygen supply unit formed at a lower end of the main body;

A fluidized bed syngas reactor having a fluidized bed formed in the upper part of the feed part and having a fluid medium and a lean bed composed mostly of gas;

And a water gas reacting part formed on the fluidized bed synthesis gas reacting part and having a catalyst layer in which a water gas conversion catalyst is present and a lean layer composed mainly of a gas, Stage gasifier in which a dispersion plate is formed and gas supply is continuously performed from the lower end to the upper end.

In another aspect, the present invention relates to a two-stage fluidized bed biogas gasifier including the two-stage fluidized bed gasifier and a biomass feeder for providing the biomass to the gasifier.

In yet another aspect,

Supplying air or oxygen and high-water biomass;

Reacting the air or oxygen, the biomass and the fluid material to produce a synthesis gas;

And a water gas reaction step of reacting water vapor generated from the biomass with carbon monoxide in the syngas with a fluid water gas catalyst, wherein the gas generated in the synthesis gas production step is continuously supplied to the aqueous gas reaction step To a method for gasifying a biomass in a two-stage fluidized bed.

The two-stage fluidized-bed biomass gasifier of the present invention can continuously perform the synthesis gas-generating reaction and the water gas conversion reaction in one single reactor composed of two stages, thereby reducing the amount of carbon monoxide to be discharged and producing hydrogen at a high concentration . In addition, since the gasification apparatus of the present invention utilizes the gas and energy generated in the synthesis gas reaction for the water gas reaction, it is economical and efficient, and it is possible to utilize the biomass resources having a high water content of 20 wt% Hydrogen gas can be produced.

1 shows a two-stage fluidized bed biomass gasification apparatus of the present invention.
Fig. 2 shows the hydrogen gas conversion rate of carbon monoxide in the gasifier of Fig.

The present invention can be all accomplished by the following description. The following description should be understood to describe preferred embodiments of the present invention, but the present invention is not necessarily limited thereto.

1 shows a two-stage fluidized bed gasifier of the present invention and a two-stage fluidized bed biomass gasifier comprising the same.

Referring to FIG. 1, the two-stage fluidized bed biomass gasifier of the present invention includes a two-stage fluidized bed gasifier 100 and a biomass injection unit 200.

The two-stage fluidized bed gasifier 100 includes a main body 10, a supply unit 20, a syngas reaction unit 30, and a water gas reaction unit 40.

In the reactor body 10, two fluidized bed reactors are continuously formed.

At the lower end of the main body 10, an air or oxygen supply part 20 is formed. The supply part 20 is filled with air or oxygen at a predetermined pressure and is supplied to the synthesis gas reaction part at a predetermined pressure and temperature.

A fluidized-bed syngas reacting section 30 is formed above the supply section 20.

The supply unit 20 and the syngas reacting unit 30 may be separated by a dispersing plate 50. Preferably, the dispersion plate may be a bubble cap type dispersion plate. 1, a bubble cap 51 is formed on the dispersion plate 50. Air or oxygen of a supply part is injected into the synthesis gas reaction part 30 through the bubble cap 51. [

The syngas reacting section 30 includes a fluidized bed 31 in which a fluid medium exists and a lean layer 32 composed mainly of a gas.

In the syngas reacting unit 30, a solid fluid medium is suspended by the air or oxygen injected from the supply unit 20, mixed with the reaction material, and gasification reaction occurs.

The flow medium is made of sand having a diameter of 100 to 500 mu m.

The syngas reacting section 30 may have a temperature range of 500 to 700 ° C. The syngas reacting section 30 is supplied with a high concentration of biomass. The biomass may have a water content of 20 wt% or more.

In the syngas reacting unit 30, air or oxygen and high-biomass react with each other to produce a syngas. Since the biomass is pyrolyzed to release carbon components and water vapor, the reaction occurs in the synthesis gas reaction unit 30 as follows.

C + air or oxygen + water vapor -> CO + hydrogen + water vapor

The gas generated in the syngas reacting unit 30 is injected into the fluidized bed water gas reacting unit 40 via the lean layer 32.

The dispersion plate 60 is formed between the synthesis gas reaction unit 30 and the fluidized-bed water gas reaction unit 40. The dispersion plate may be a bubble cap type dispersion plate. 1, a bubble cap 61 is formed on the dispersion plate 60 and a gas is injected from the syngas reaction unit 30 through the bubble cap 61.

The fluidized-bed water-gas reaction unit 40 includes a catalyst layer 41 in which a water gas shift catalyst is present and a lean layer 42 composed mainly of a gas.

As the water gas shift catalyst, known catalysts can be used, and preferably a high temperature water gas shift catalyst can be used. For example, as the catalyst, a Fe 3 O 4 catalyst containing 8 to 12 wt% CrO 3 may be used.

The water gas shift catalyst may be flowed by the gas injected through the dispersion plate 60.

In the fluidized-bed aqueous gas reacting section 40, the gases generated in the synthesis gas reacting section 30 react with water gas generated from the biomass and carbon monoxide in the synthesis gas with the water gas catalyst.

Water vapor + CO -> Hydrogen + CO2

The water gas conversion reaction may be performed at a temperature in the range of 400 to 550 ° C.

Hydrogen gas and carbon dioxide generated in the fluidized bed water gas reacting section 40 are discharged through the discharge section 43 via the lean layer 42.

The two-stage fluidized bed gasifier of the present invention can perform the synthesis gas reaction and the water gas conversion reaction continuously in one single reactor, thereby reducing the amount of carbon monoxide to be discharged and producing hydrogen at a high concentration.

In another aspect, the present invention relates to a two-end fluidized bed biomass gasifier 1000. The two-stage fluidized bed biomass gasifier 1000 includes the two-stage fluidized-bed gasifier 100 and the biomass injection unit 200.

The two-stage fluidized bed gasifier 100 includes a main body 10, a supply unit 20, a syngas reaction unit 30, and a water gas reaction unit 40. The above-described two-stage fluidized-bed gasifier 100 can be referred to above.

The biomass injector 200 provides biomass to the gasifier. The biomass injection unit 200 includes a storage unit 210 and a supply unit 220.

The supply unit 220 may use a screw type.

The biomass injection unit 200 supplies the biomass to the fluidized bed synthesis gas reacting unit 30 through the connection unit 33.

The supply unit 220 includes a cooling unit 230 to prevent the high water content of the biomass from being dried and pyrolyzed. The cooling unit 230 is supplied with cooling water in the form of a double pipe to maintain the temperature of the injection unit at 60 ° C or lower.

The biomass can be pulverized to an appropriate size and supplied, for example, to have a diameter of 5 mm or less.

The two-stage fluidized bed biogas gasifier 1000 may include a separator 300 for separating the exhaust gas and foreign matter from the downstream of the two-stage fluidized bed gasifier 100. The separator may be a cyclone.

The two-stage fluidized bed biomass gasifier 1000 may include a preheater (not shown) that heats air or oxygen using the gas discharged from the fluidized bed water gas reacting unit 40.

In another aspect, the present invention relates to a two-stage fluidized bed biomass gasification process.

The two-stage fluidized bed gasification process includes a feed step, a synthesis gas production step and a water gas reaction step.

The feeding step is to supply air or oxygen and high-water biomass.

The synthesis gas producing step is a step of producing a synthesis gas by reacting the air or oxygen, the biomass, and the fluid material, as described above.

The water gas reaction step is a step of reacting water vapor generated from the biomass and carbon monoxide in the syngas with a water gas conversion catalyst.

In the two-stage fluidized bed gasification method of the present invention, the gas generated in the synthesis gas production step is continuously injected into the aqueous gas reaction step. In addition, the process of the present invention can be carried out in one single reactor in which the synthesis gas production step and the water gas reaction step are carried out. In addition, the method of the present invention is performed in a fluidized bed process in which the synthesis gas production step and the water gas reaction process are performed.

The synthesis gas production step may be performed at a temperature ranging from 500 to 700 ° C, and the aqueous gas reaction step may be operated at a temperature ranging from 400 to 550 ° C.

The reaction of the aqueous gas may be performed using the high temperature gas and heat generated in the synthesis gas production step.

Fig. 2 shows the hydrogen gas conversion rate of carbon monoxide in the gasifier of Fig. More specifically, referring to FIG. 2, the conversion rate (400) of carbon monoxide converted in the water gas reaction part is 50%, and the discharged gases are mostly hydrogen and carbon dioxide, and the carbon monoxide exists in 10% or less . That is, it can be seen that the two-stage fluidized bed gasifier of the present invention can produce more than 50% of hydrogen and close to 40% of carbon dioxide.

It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

10: main body 20:
30: Synthetic gas reaction part 40: Water gas reaction part
50, 60: Dispersion plate 51, 61: Bubble cap
100: Two-Stage Fluidized Bed Gasifier 200: Biomass Injection Unit
210: storage unit 220:
230: Cooling section 300: Separation section

Claims (9)

A reactor body;
An air or oxygen supply unit formed at a lower end of the main body;
A fluidized bed syngas reactor having a fluidized bed formed in the upper part of the feed part and having a fluid medium and a lean bed composed mostly of gas;
And a water gas reacting part formed on the fluidized bed synthesis gas reacting part and having a catalyst layer in which a water gas conversion catalyst is present and a lean layer composed mainly of a gas, And the gas supply is continuously performed from the lower end to the upper end of the gasifier. The method according to claim 1, wherein the fluidized-bed synthesis gas reacting unit reacts air or oxygen, biomass, and fluid material to produce a syngas,
Wherein the fluidized bed water gas reacting unit reacts the water vapor generated from the biomass and the carbon monoxide in the syngas with the water gas catalyst. 2. The gasifier according to claim 1, wherein the dispersion plate is a bubble cap type dispersion plate, and the fluid medium and the water gas shift catalyst are flowed by a gas injected through the dispersion plate. A two-stage fluidized bed biogas gasifier comprising a two-stage fluidized-bed gasifier according to any one of claims 1 to 3 and a biomass injector for providing biomass to the gasifier. [5] The apparatus of claim 4, wherein the biomass is a high-concentration biomass having a moisture content of 20 wt%. [6] The apparatus of claim 5, wherein the biomass injection unit includes a cooling unit for supplying the biomass to the fluidized-bed syngas reacting unit and maintaining the temperature of the injection unit at 60 [deg.] C or lower. The gasification apparatus of claim 1, wherein the gasifier includes a preheater for heating air or oxygen using the gas discharged from the fluidized bed water gas reacting unit. Supplying air or oxygen and high-water biomass;
Reacting the air or oxygen, the biomass and the fluid material to produce a synthesis gas;
And a water gas reaction step of reacting water vapor generated from the biomass with carbon monoxide in the syngas with a fluid water gas catalyst, wherein the gas generated in the synthesis gas production step is continuously supplied to the aqueous gas reaction step Is injected into the second fluidized bed biomass gasification process. The method of claim 7, wherein the synthesis gas production step is operated at a temperature of 500 to 700 ° C, and the aqueous gas reaction step is operated at a temperature of 400 to 550 ° C.

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