JPWO2020008622A1 - Hydrogen production method using biomass as a raw material - Google Patents

Abstract

The thermal decomposition step includes a thermal decomposition step of supplying a heat-bearing medium to obtain a thermal decomposition gas from a biomass raw material, and a reforming step of raising the temperature of the thermal decomposition gas to obtain a reformed gas rich in hydrogen. The heat-bearing medium is heated to 680 to 740 ° C., and in the thermal decomposition step, water vapor and oxygen gas are simultaneously supplied to set the thermal decomposition reaction temperature to 640 to 740 ° C., and in the reforming step, A hydrogen production method using biomass as a raw material, in which water vapor and oxygen gas are simultaneously supplied and the heat-bearing medium is not supplied in the reforming step.

Description

The present invention relates to a hydrogen production method using biomass as a raw material.

When hydrogen is used as a fuel, it does not emit carbon dioxide and is regarded as an important environmentally friendly material. For example, hydrogen is supplied to a fuel cell to be used as a fuel cell vehicle or a fuel cell power plant. As a result, the power generation efficiency is expected to improve dramatically, and it is expected that the demand will increase more and more in the future.

On the other hand, proposals have been made for producing hydrogen from biomass instead of fossil fuels such as petroleum and natural gas.

For example, in Patent Document 1,
A method for producing a product gas having a high calorific value from an organic substance and a substance mixture.
The circulating heat-bearing medium passes through the heating zone, reaction zone, pyrolysis zone and separation step and continues back to the heating zone, at which time.
By contacting the organic material or substance mixture with a heat-bearing medium heated in the pyrolysis zone, it is separated into a pyrolysis gas as a solid carbon-containing residue and a volatile phase.
After passing through the pyrolysis zone, the solid carbon-containing residue is separated from the heat-bearing medium in a separation step.
The pyrolysis gas is mixed with steam as a reaction medium, and by exchanging a part of the heat contained in the heat-bearing medium heated in the reaction zone, the product gas having a high calorific value is further heated. In the method of producing a product gas with a high calorific value from an organic substance and a substance mixture.
Water vapor is mixed with the pyrolysis gas in the pyrolysis zone,
Supply all solid carbon-containing residues to another combustion device, where it burns,
A high calorific value from an organic substance and a substance mixture, characterized in that the hot exhaust gas of this combustion apparatus is passed through the deposition of a heat-bearing medium existing in the heating zone, and most of the sensible heat is given to the heat-bearing medium at that time. A method for producing a product gas having the above is described.

Further, for example, in Patent Document 2,
The organic waste is heated at 500-600 ° C. in a non-oxidizing atmosphere using a heat-bearing medium, the generated pyrolysis gas is mixed with steam at 900-1000 ° C., and then the obtained reformed gas is purified. The method for recovering hydrogen is described.

Japanese Patent No. 4264525 Japanese Patent No. 4246456

Although the methods described in the above patent documents aim to obtain hydrogen gas, tar is generated by a thermal decomposition reaction and the pipeline is blocked by tar, so that hydrogen gas can be stably obtained for a long period of time. Has the problem of being difficult.

The present invention solves this problem and is as follows.
The method for producing hydrogen using biomass as a raw material according to one aspect of the present invention includes a pyrolysis step of supplying a heat-bearing medium to obtain a pyrolysis gas from the biomass raw material, and a thermal decomposition step of raising the temperature of the pyrolysis gas to be rich in hydrogen. It has a reforming step of obtaining a reforming gas, and the heat-bearing medium in the thermal decomposition step is heated to 680 to 740 ° C. In the thermal decomposition step, steam and oxygen gas are further supplied at the same time. The pyrolysis reaction temperature is set to 640 to 740 ° C., and in the reforming step, steam and oxygen gas are simultaneously supplied, and the heat-bearing medium is not supplied to the reforming step.

According to the above, the tar generated by the thermal decomposition reaction is completely decomposed, and hydrogen gas can be stably produced for a long period of time.

It is the schematic of an example of the apparatus (equipment) for carrying out one aspect of this invention.

<Explanation of Embodiments of the Present Invention>
First, embodiments of the present invention will be listed and described.
When the numerical range is expressed by "~" in the present specification and the claims, the range includes the numerical values of the upper limit and the lower limit. In addition, "/" represents division.

(1) The method for producing hydrogen using biomass as a raw material according to one aspect of the present invention includes a pyrolysis step of supplying a heat-bearing medium to obtain a pyrolysis gas from the biomass raw material, and raising the temperature of the pyrolysis gas. It has a reforming step of obtaining a reforming gas rich in hydrogen, and the heat-bearing medium in the thermal decomposition step is heated to 680 to 740 ° C. In the thermal decomposition step, steam and oxygen gas are further simultaneously used. The pyrolysis reaction temperature is set to 640 to 740 ° C., and in the reforming step, steam and oxygen gas are simultaneously supplied, and the heat-bearing medium is not supplied to the reforming step. This hydrogen production method can completely decompose the generated tar and stably obtain hydrogen gas for a long period of time. In addition, diphosphorus pentoxide (P ₂ O _{5 ) may be contained in the biomass raw material, but P 2} O ₅ evaporation can be suppressed by setting the thermal decomposition temperature to 640 to 720 ° C.

(2) In the thermal decomposition step of the hydrogen production method, the molars of steam and oxygen gas vapor / oxygen gas that are simultaneously supplied are 1 to 4. As a result, the thermal decomposition reaction temperature can be easily set to 640 to 740 ° C.

(3) The thermal decomposition temperature of the thermal decomposition step of each hydrogen production method is 660 to 700 ° C. As a result, the generation of tar is further suppressed, and hydrogen gas can be stably obtained for a long period of time.

<Details of Embodiments of the present invention>
One aspect for carrying out the present invention will be described in detail below, but first, the findings and ideas from which the aspect has been derived will be described.

When the present inventor examined the hydrogen production methods described in Patent Documents 1 and 2 described above, the reason why tar did not decompose was that the temperature in the pyrolyzer could not be secured at 640 ° C. or higher, which will be described later. I found that there is.
Therefore, in order to raise the temperature in the thermal decomposer, in the hydrogen production methods described in the above-mentioned Patent Documents 1 and 2, it was examined to raise the temperature of the heat-bearing medium to be preheated. In the case, the preheated heat-bearing medium is input to the thermal cracker via the reformer, and the heat possessed by the heat-bearing medium is first used as the heat source of the reformer. In order to raise the thermal decomposition temperature for tar decomposition, it is necessary to further increase the preheating temperature of the heat-bearing medium in the preheater, that is, preheating exceeding 1050 ° C., but this further increase in the preheating temperature is industrial. From a point of view, it was found that it was not realistic and it was difficult to raise the temperature of the reformer using the heat-bearing medium to 1000 ° C.
The "heating zone", "reaction zone", and "pyrolysis zone" referred to in Patent Document 1 are discussed as "preheater", "modifier", and "pyrolysis device" in the present invention, respectively. I am doing.

Therefore, the present inventor conducted a further study and found that
(1) In order to suppress the generation of tar to the extent that it does not hinder the production of hydrogen, it is necessary to raise the thermal decomposition reaction temperature to 640 ° C or higher, and it is difficult to raise the temperature to 1000 ° C in the reformer. Based on this finding, we obtained the finding that the reason is that the heat transfer coefficient between the heat-bearing medium and the reforming gas is small.
(2) The idea is that the heat source of the pyrolyzer is not limited to the heat-supporting medium, but the amount of heat that is insufficient due to the heat-supporting medium alone is supplemented by another heat source.
(3) The preheated heat-bearing medium is not charged to the reformer, but only to the pyrolyzer, and if it is used as heat for raising the temperature to the pyrolysis temperature of the pyrolyzer and evaporating water, heat is generated. The preheating temperature of the carrying medium can be lowered,
(4) If the partial oxidation reaction heat generated by blowing oxygen gas as another heat source for the pyrolysis reaction of the pyrolyzer is used, the temperature can be easily raised to a predetermined pyrolysis reaction temperature, and this At the same time, by blowing water vapor at the same time, the sensitivity of the reaction temperature due to insufficient oxygen is alleviated and temperature control becomes easier.
(5) In the reformer, if oxygen gas is supplied instead of the heat-carrying medium, the temperature can be easily raised to the reforming reaction temperature of 1000 ° C. by the heat of partial oxidation reaction, and at this time, steam is added. By blowing at the same time, the sensitivity of the reaction temperature due to insufficient oxygen is alleviated and temperature control becomes easier.
I got new knowledge and ideas from.
Next, a mode for carrying out the present invention will be described based on the findings and matters related to the idea. First, each process will be described.

Heat-supporting medium (1) Shape and material of heat-supporting medium The shape of the heat-supporting medium is preferably a sphere, and the material is preferably ceramic or steel such as alumina. That is, alumina balls, ceramic balls, and steel balls can be used, and the diameter thereof is preferably 10 to 30 mm.
(2) Preheating temperature The heat-carrying medium is preheated by a preheater, and the preheating temperature range is 680 to 740 ° C. This preheating temperature range is much lower than 1050 ° C. shown in Patent Documents 1 and 2, energy required for preheating can be saved, thermal efficiency is improved, and an expensive refractory material is used for the preheater. It brings the advantage of not having to do it.
The heat-supporting medium 24 is heated by the preheater 3, heat is applied to the reaction as a heat-supporting medium for thermal decomposition by the thermal decomposition device 4, and the char and the heat medium are separated by the char separation device 6, and then the heat-supporting medium 24 is separated. It is circulated and used in the circulation device 27.

Pyrolysis reaction process in the pyrolyzer:
The pyrolysis reaction in the pyrolyzer will be described in detail.

(1) Biomass raw material:
The raw material used in one embodiment of the present invention is biomass, which is carbon derived from living organisms such as sewage sludge, thinned wood, flowing wood, wood pellets, straw pellets, paper sludge, food waste compost sludge, food waste, sludge, etc. Any type of sludge containing hydrogen and oxygen is acceptable, but sewage sludge is preferable because of its availability. Further, the raw material may be a mixture of a plurality of types of biomass.
The size of the biomass may be as large as it has undergone the coarse pulverization treatment. For example, a solid shape such as a plate having a length of 15 mm or less and a granular shape are preferable. The amount of water contained varies depending on the shape, but it is preferably pre-dried before being supplied to the pyrolyzer in an amount of 30 to 20% by mass.

(2) Obtaining pyrolysis gas Pyrolysis:
The temperature of the pyrolysis for obtaining the pyrolysis gas is 640 to 740 ° C. The reason for setting this temperature range is that if the temperature is lower than 640 ° C, it is difficult to completely decompose the tar generated by thermal decomposition, and if it exceeds 740 ° C, an excessive heat source is required to completely decompose the tar. Because. The thermal decomposition temperature is more preferably 660 to 700 ° C.

Further, when sewage sludge or the like is used as an organic raw material, diphosphorus pentoxide (P ₂ O _{5 ) is contained in the organic raw material, but P 2} O ₅ evaporation is caused by setting the thermal decomposition temperature to 640 to 740 ° C. inhibition can, for volatilization vapor P ₂ O ₅ which may cause clogging trouble pyrolysis gas does not exist, has the advantage that it is possible to an organic material sewage sludge containing P ₂ O _5.
The heat source for thermal decomposition is provided by a heat-carrying medium, but that alone is not sufficient, and oxygen gas is blown and supplied to bring the temperature into the above temperature range.

By securing a heat source by simultaneously blowing and supplying water vapor and oxygen gas, heat transfer by supplying water vapor and oxygen gas is far more efficient than heat transfer of a heat-bearing medium that is a solid phase. , The supplied steam suppresses the formation of heat spots, can mitigate sudden changes in temperature, and controls the thermal decomposition reaction in response to disturbances that change in a short time, such as changes in the amount of organic raw materials supplied. It has the advantage of being easy.

Here, the respective supply ratios of water vapor and oxygen gas are preferably 1 to 4 in terms of the molar ratio of water vapor / oxygen gas (molar of water vapor / mol of oxygen gas). The reason for setting this range is that if it is less than 1, the temperature fluctuation may become large, and if it exceeds 4, the water vapor becomes oxidizing at 600 ° C. or higher, and the CO ₂ concentration becomes large, which is not preferable for hydrogen recovery. This is because it will be stored.
Although the temperature of the water vapor is not limited, an example thereof may be one having a temperature of 140 ° C., and the oxygen gas is not particularly limited. For example, 40 produced by an industrial oxygen gas generator. Those having a temperature of about ° C can be used. The higher the molar ratio represented by water vapor / oxygen gas, the easier it is to control the pyrolysis reaction against disturbances caused by slight fluctuations in the oxygen flow rate.

Here, the pyrolysis gas is a gas whose main components are _{CH 4} , CO, CO ₂ , and H _2. By blowing steam, as described above, it is possible to obtain a H _2, because the content of H ₂ is small and 10% by volume, in order to increase the content of H _2, modification in the next step I do.

Reforming process in the reformer:
The reformer is installed downstream of the pyrolyzer, and steam and oxygen gas are simultaneously supplied without using a heat-bearing medium as a heat source to raise the temperature to 1000 ° C or higher and the pyrolysis gas is subjected to coarse hydrogen-rich crude. Obtain reformed gas. Then, instead of supplying the heat-supporting medium, the temperature can be easily raised to 1000 ° C. by simultaneously supplying water vapor and oxygen gas.
Here, as an example, the water vapor may have a temperature of 100 to 150 ° C., and the oxygen gas may have a temperature of 40 ° C. manufactured by an industrial oxygen gas generator, for example.

By the reforming, the steam reforming reaction proceeds, _{the hydrocarbon gas such as CH 4} gas is converted into hydrogen gas, and the content ratio of hydrogen gas increases. Here, as a typical steam reforming reaction,
CH ₄ + H ₂ O → CO + 3H ₂
Can be mentioned.
In addition, the next shift reaction also proceeds, and the hydrogen gas content increases.
CO + H ₂ O → CO ₂ + H ₂
The thus obtained crude reformed gas, the content of H ₂ gas is in the 50 to 54 vol% (dry basis).
The supply of steam is not only for advancing the steam reforming reaction, but also for alleviating temperature sensitivity (rapid change).
As an example, it is preferable that the steam and oxygen gas supplied to the reformer are simultaneously supplied so that the molar ratio of water vapor / oxygen gas (molar of water vapor / mol of oxygen gas) is 1 to 4.

H ₂ gas purification steps:
The gas (crude reformed gas) that has undergone the reforming step is cooled and dust-removed to remove trace amounts of harmful components such as _{HCl, CN, and NH 3.} Here, the removal can be performed by appropriately combining conventionally known means. Thereafter, the purification of _{H 2} gas. Purification of the H ₂ gas may be appropriately using known means, for example, PSA unit, the membrane separation means can be used.

Next, examples will be described, but it goes without saying that the present invention is not limited to these examples and can be appropriately modified without departing from the spirit of the present invention.

Using the apparatus (equipment) shown in FIG. 1, each example and each comparative example described below were carried out. Hereinafter, each step will be described with reference to a schematic diagram which is an example of an apparatus for carrying out the present invention shown in FIG.

The heat-supporting medium 24 is heated (preheated) at 680 to 740 ° C. by the preheater 3, and after heating, is charged into the pyrolyzer 4 via the valve 25. Here, the heat source for preheating the heat-bearing medium with the preheater 3 is a combustion exhaust gas 19 at about 800 ° C. in which a part 18 of the char and a part of the pyrolysis gas 11 are burned in the combustion furnace 23, as will be described later. Yes, the combustion exhaust gas 20 is discharged from the preheater 3.

The pyrolysis step is performed by the pyrolyzer 4, and the biomass raw material 1 is supplied to the pyrolyzer 4 by a biomass raw material transfer device 2 such as a screw conveyor. The biomass raw material 1 is heated by the heat from the input heat-bearing medium 24 and the steam 8 and oxygen gas 7 simultaneously blown and supplied from the lower part of the pyrolyzer 4, and heats at a temperature of 640 to 720 ° C. It is decomposed and a pyrolysis gas 11 is generated.

The reforming step is performed by the reformer 5. Most of the pyrolysis gas 11 obtained by the pyrolysis reaction is sent to the reformer 5. In the reformer 5, steam 10 and oxygen gas 9 are simultaneously blown and supplied from the lower part thereof, the temperature of the pyrolysis gas 11 is raised to 1000 ° C., the above-mentioned steam reforming reaction is allowed to proceed, and the crude reforming gas 13 is carried out. To get.

Purification process of the H ₂ gas is made at Soaratameshitsu gas cooling and purifying device 21, crude reformed gas 13 that has passed through the reformer 5 is introduced into Soaratameshitsu gas cooling and purifying device 21, each unit Although not shown, cooling, dust removal, and removal of trace amounts of harmful components are performed to obtain a refined reformed gas 14, which is introduced into a hydrogen separator 22 to obtain a pure hydrogen gas 15. The off-gas 16 is discharged from the hydrogen separator 22.

Further, from the bottom of the pyrolyzer 4, the char of the heat-carrying medium 24 and the biomass raw material 1 having reached about 640 ° C. is discharged, and these are introduced into the char separating device 6 via the valve 26. In the char separation device 6, the char 17 and the heat-supporting medium 24 are separated, and the heat-supporting medium 24 is sent to the heat-supporting medium circulation device 27, returned to the preheater 3 by the device, and used for circulation. The char 17 is used as an alternative fuel in a cement manufacturing facility or a coal-fired power plant, except for a part 18 of the char. As the char separating device 6, a known one such as one capable of separating the heat-supporting medium 24 and the char 17 by a sieve can be used.

Here, as described above, a part 12 of the pyrolysis gas and a part 18 of the char are introduced into the combustion furnace 23 and burned to become a heat source for the combustion exhaust gas 19 at about 800 ° C. It serves as a heat source for preheating the heat-bearing medium 24 with a preheater. When only a part 12 of the pyrolysis gas and a part 18 of the char are insufficient as a heat source for this preheating, an external fuel such as LNG or LPG is used to supplement the heat source. It is not necessary to use a special combustion furnace 23.

Although not shown, in this device (equipment), steam is produced by using the waste heat of the combustion exhaust gas 20 of the preheater, and this is supplied to the steam 8 and the reformer. It is also possible to use the steam 10 to be used.

The organic raw material commonly used in each Example and each Comparative Example is sewage sludge, which is as follows.

Supply amount 27.2 kg / h
Moisture content 20% by mass
The proportions of ash, volatile and fixed carbon, and the results of elemental analysis are shown in Tables 1 and 2, respectively.

In common with each Example and each Comparative Example, the alumina balls shown in Table 3 were used as the heat-carrying medium.

<Example 1>
The preheating temperature of the heat-bearing medium was 700 ° C., the temperature of the pyrolyzer (pyrolysis reaction temperature) was 690 ° C., and steam at 140 ° C. and oxygen gas at 40 ° C. were blown into the medium. At this time, the oxygen gas flow rate and the steam flow rate to the thermal cracker are 1.71 Nm ³ / h and 2.75 kg / h, respectively, and the molar ratio of steam / oxygen gas is 2.0 (= (2.75 ×). 10 ³ /18)/(1.71×10 ³ /22.4)), an oxygen gas flow rate, steam flow rate to the reformer, respectively, were 2.3Nm ³ /h,3.7kg/h.
In addition, the pyrolysis gas composition, the amount of tar, and the gas composition leaving the reformer were measured. The results are shown in Table 4.
In the display of the pyrolysis gas composition, all hydrocarbon gases were represented by _{CH 4.} Hereinafter, the same notation is used.

<Comparative example 1>
The preheating temperature of the heat-carrying medium was 700 ° C., the temperature of the pyrolyzer was 600 ° C., and steam at 140 ° C. and oxygen gas at 40 ° C. were blown into the heat-carrying medium. At this time, the oxygen gas flow rate and the steam flow rate to the thermal cracker are 0.76 Nm ³ / h and 1.21 kg / h, respectively, the molar ratio of steam / oxygen gas is 2.0, and the oxygen gas to the reformer. The flow rate and the steam flow rate were 2.3 Nm ^{3 /} h and 3.7 kg / h, respectively. The pyrolysis gas composition and the amount of tar were measured. The results are shown in Table 4.

In Example 1, the temperature of the pyrolyzer is 690 ° C., which is in the temperature range of 650 to 740 ° C., and the molar ratio of water vapor / oxygen gas is 2.0, which is in the molar ratio range of 1.0 to 4.0. _{Therefore, the content ratio of CH 4} gas contained in the pyrolysis gas was low, and the generation of tar could be completely suppressed. Moreover, the temperature of the reformer could be set to 1000 ° C.
On the other hand, in Comparative Example 1, since the pyrolysis temperature was 600 ° C. and was not in the above temperature range, _{the content ratio of CH 4} gas contained in the pyrolysis gas was high, tar was generated, and the reformer was used. The temperature was 937 ° C.

_{Next, in order to confirm that the evaporation of P 2} O ₅ contained in the sewage sludge _{is suppressed, P 2} deposited in the crude reformed gas cooling / refining apparatus 22 of FIG. 1 in Example 2 and Comparative Example 2. the amount of O ₅ was measured.

<Example 2>
The preheating temperature of the heat-carrying medium was 700 ° C., the temperature of the pyrolyzer was 690 ° C., and steam at 140 ° C. and oxygen gas at 40 ° C. were blown into the heat-carrying medium. At this time, the oxygen gas flow rate and the steam flow rate to the pyrolyzer were 1.71 Nm ³ / h and 2.75 kg / h, respectively, and the steam / oxygen gas molar ratio was 2.0, and the operation was performed for 5 hours. , The amount of _{P 2} O ₅ deposited on the crude reformed gas cooling / refining apparatus 22 of FIG. 1 was measured. The results are shown in Table 5.

<Comparative example 2>
The preheating temperature of the heat-carrying medium was set to 800 ° C., the temperature of the pyrolyzer was set to 780 ° C., and steam at 140 ° C. and oxygen gas at 40 ° C. were blown into the heat-carrying medium. At this time, the oxygen gas flow rate and the steam flow rate to the pyrolyzer were 3.14 Nm ³ / h and 5.0 kg / h, respectively, and the steam / oxygen gas molar ratio was 2.0, and the operation was performed for 5 hours. , The amount of _{P 2} O ₅ deposited on the crude reformed gas cooling / refining apparatus 22 of FIG. 1 was measured. The results are shown in Table 5.

The estimated P ₂ O ₅ steam concentration was estimated from the amount of the blockage that blocked the crude reformed gas cooling / purification apparatus 22 and the analysis result thereof.

In Example 2, the temperature of the pyrolyzer is 690 ° C. and is in the temperature range of 650 to 740 ° C., and the molar ratio of water vapor / oxygen gas is 2.0 and the molar ratio range is 1.0 to 4.0. _{Therefore, the amount of P 2} O ₅ deposited in the crude reformed gas cooling / refining equipment is as small as 0.02 kg, and it can be said that the evaporation of _{P 2} O _{5 contained in the sewage sludge is almost completely suppressed.} ..
On the other hand, in Comparative Example 2, the thermal decomposition temperature was 780 ° C., which was higher than the temperature range, and _{the evaporation of P 2} O ₅ was not suppressed.

Next, in order to confirm the influence of the molar ratio of water vapor / oxygen gas on _{the yield of H 2} and the stability of temperature fluctuation, it is compared with Example 3 and Example 2.

<Example 2>
Example 2 was carried out as described above, but the amount of pyrolysis gas was 16.64 Nm ³ / h, and the amount of oxygen gas blown was ± 0.30 Nm ³ / h. The fluctuation in the temperature of the decomposer was ± 60 ° C. The composition of the obtained crude reformed gas is shown in Table 6.

<Example 3>
The preheating temperature of the heat-carrying medium was 700 ° C., the temperature of the pyrolyzer was 690 ° C., and steam at 140 ° C. and oxygen gas at 40 ° C. were blown into the heat-carrying medium. At this time, the flow rates of oxygen gas and steam to the pyrolyzer were 1.71 Nm ³ / h and 5.49 kg / h, respectively, and the molar ratio of steam / oxygen gas was 4.0. The composition of the obtained pyrolysis gas is shown in Table 6.

Comparing Example 2 and Example 3, the higher the molar ratio of water vapor / oxygen gas, the more the fluctuation of the thermal decomposition reaction temperature can be suppressed with respect to the fluctuation of the oxygen gas flow rate, and the fluctuation of the oxygen gas flow rate. It can be said that the hypersensitivity of the resulting temperature change is improved.

It should be considered that the embodiments disclosed this time are exemplary in all respects and are not restrictive. The scope of the present invention is not the embodiment described above, but is indicated by the claims and includes all modifications of the equivalent scope of the matters described in the claims.

1 Biomass raw material 2 Biomass raw material transfer device 3 Preheater 4 Thermal decomposition device 5 Reformer 6 Char separation device 7 Oxygen gas 8 Steam 9 Oxygen gas 10 Steam 11 Thermal decomposition gas 12 Part of thermal decomposition gas 13 Crude reformed gas 14 Refined reformed gas 15 Product Pure hydrogen gas 16 Off-gas 17 Char 18 Part of char 19 Combustion exhaust gas 20 Combustion exhaust gas 21 Coarse reformed gas Cooling / refining device 22 Hydrogen separator 23 Combustion furnace 24 Heat-bearing medium 25 Valve 26 Valve 27 Heat Carrying medium circulation device

Claims (3)

A pyrolysis step of supplying a heat-supporting medium to obtain a pyrolysis gas from a biomass raw material, and
A reforming step of raising the temperature of the pyrolysis gas to obtain a reformed gas rich in hydrogen.
Have,
The heat-carrying medium in the thermal decomposition step is heated to 680 to 740 ° C.
In the thermal decomposition step, steam and oxygen gas are further supplied at the same time to set the thermal decomposition reaction temperature at 640 to 740 ° C.
In the reforming step, steam and oxygen gas are simultaneously supplied.
The heat-supporting medium shall not be supplied to the reforming step.
A hydrogen production method using biomass as a raw material. The method for producing hydrogen using biomass as a raw material according to claim 1, wherein in the thermal decomposition step, the molars of steam and oxygen gas that are simultaneously supplied are 1 to 4. The method for producing hydrogen using biomass as a raw material according to claim 1 or 2, wherein the thermal decomposition reaction temperature in the thermal decomposition step is 660 to 700 ° C.

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