JP4797241B2 - Reformer - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a reformer that generates hydrogen gas from a predetermined liquid raw material.
[0002]
[Prior art]
A reformer that generates hydrogen gas by a reforming reaction from various compounds containing hydrogen atoms, for example, hydrocarbons such as gasoline, alcohols such as methanol, ethers, and aldehydes has been proposed.
[0003]
FIG. 5 is an explanatory diagram showing a reformer of the reformer. The reformer of the reformer, for example, when methanol is used as the reforming raw material, is around a cylindrical honeycomb unit 142 (hereinafter referred to as catalyst-supporting honeycomb) 142 supporting a Cu—Zn base metal catalyst. Is covered with a metal case 144 using the alumina mat 152 as a buffer material. Some reforming apparatuses are installed so that the gas flows in the horizontal direction in the reforming section (FIG. 5A) and those installed so that the gas flows vertically (FIG. 5B). Generally, as a reformer for mounting on a fuel cell vehicle, a horizontal installation type is adopted because of the limitation in the height direction in terms of vehicle mountability.
[0004]
Vaporized methanol and water are supplied to the reformer, and hydrogen gas is generated by a steam reforming reaction represented by the following formula (1).
[0005]
CH ₃ OH + H ₂ O → CO ₂ + 3H ₂ −49.5 (kJ / mol) (1)
[0006]
In addition, it can be considered that the steam reforming reaction of the formula (1) is the result of two reactions shown in the following formulas (2) and (3).
[0007]
CH ₃ OH → CO + 2H ₂ -90.0 (kJ / mol) (2)
CO + H ₂ O → CO ₂ + H ₂ +40.5 (kJ / mol) (3)
[0008]
Since the steam reforming reaction of the formula (1) is an endothermic reaction, the operating temperature of the reformer is set using heat generated by the exothermic action of the partial oxidation reaction shown in the following formula (4) by introducing air (oxygen). It is also maintained.
[0009]
CH ₃ OH + (1/2) O ₂ → CO ₂ + 2H ₂ +189 (kJ / mol) (4)
[0010]
When the reformer is started, the heat generated by the exothermic action of the partial oxidation reaction and the exothermic action of the reaction shown in the following equation (5) is used for raising the temperature of the reformer.
[0011]
H ₂ + (1/2) O ₂ → H ₂ O + 240 (kJ / mol) (5)
[0012]
[Problems to be solved by the invention]
However, in the initial stage of the warm-up operation of the reformer, the vaporized methanol is condensed because the temperature of the reformer is low. The condensate may soak into the alumina mat 152. If it does so, the thermal energy shown to Formula (4) and (5) will be consumed in order to re-evaporate the condensate which soaked in the alumina mat | matte 152, and the starting time of a reformer (temperature raising time of a reformer) is prolonged. Make it.
[0013]
Further, when the condensate soaked in the alumina mat 152 comes to re-evaporate as the catalyst supporting honeycomb 142 rises in temperature, the methanol concentration in the reforming portion becomes high, and a part of the methanol remains unmodified and the reformer It flows downstream. This unmodified methanol is corrosive and therefore adversely affects subsequent processes. Even when a liquid raw material other than methanol is used as the reforming raw material, the unreformed gas may adversely affect the subsequent process.
[0014]
The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a technique for efficiently shortening the start-up time of a reformer using a liquid raw material.
[0015]
[Means for solving the problems and their functions and effects]
In order to solve at least a part of the above-described problems, the present invention employs the following configuration.
The reformer of the present invention comprises:
A reformer that generates hydrogen gas from a predetermined liquid raw material,
An evaporation section for evaporating the liquid material;
A reforming section for generating hydrogen gas from the evaporated raw material by a reforming reaction;
At least the condensate removing means for removing the condensate condensed in the reforming section,
It is a summary to provide.
[0016]
In the reformer of the present invention, hydrogen gas is generated from a predetermined liquid raw material by a reforming reaction. As the predetermined liquid raw material, various compounds containing hydrogen atoms, for example, hydrocarbons such as gasoline, alcohols such as methanol, ethers and aldehydes can be used. In the present invention, even if the vaporized source gas is condensed, the condensate can be quickly removed by the condensate removing means. As a result, the loss of heat energy consumed for vaporizing the condensate can be reduced, and the temperature of the reforming section can be increased efficiently. As a result, the temperature raising time of the reforming unit, that is, the start-up time of the reformer can be efficiently shortened.
[0017]
In the present invention, since the condensate is removed, it is possible to suppress the raw material gas from flowing out to the downstream side of the reformer without being reformed. As a result, the adverse effect of the unreformed gas on the subsequent process of the reformer can be suppressed.
[0018]
In the reforming apparatus of the present invention, the condensate removing means rotates the reforming section at a high speed around the gas flow direction, removes the condensate by centrifugal force, or tilts the reforming section and removes it by gravity. Although it is possible to be a means to
The condensate removing means may be means for repelling the condensate.
[0019]
As the means for repelling the condensate, for example, a material repelling the condensate may be used, or a surface treatment for repelling the condensate may be performed. By doing so, there are advantages such that power is unnecessary and space saving can be achieved.
[0020]
In the reformer of the present invention, it is effective to provide a condensate removing means at a place where the condensate tends to stay.
For example, when the reforming unit includes a unit carrying a reforming catalyst, a case covering the unit, and a cushioning material provided between the unit and the case,
The condensate removal means may be means for removing the condensate from at least the buffer material.
[0021]
In the portion of the cushioning material that serves as a cushion between the unit supporting the reforming catalyst and the case, the condensate permeates as it is, which tends to hinder the temperature rise of the reforming unit. By providing the means for removing the condensate from the buffer material, it is possible to reduce the loss of heat energy consumed for vaporizing the condensate and efficiently raise the temperature of the reforming unit.
[0022]
In the reformer of the present invention,
Furthermore, a recovery means for recovering the removed condensate may be provided.
[0023]
By recovering the condensate, it can be reused as a reforming raw material. As a result, the raw material utilization efficiency can be improved.
[0024]
In the above reformer,
The recovery means is preferably provided upstream of the reforming unit.
[0025]
Condensation is likely to occur upstream of the reforming section. Therefore, the condensate can be effectively recovered by providing the recovery means on the upstream side of the reformed gas. The upstream side of the reforming unit may be, for example, a pipe for supplying gas to the reforming unit, or may be an upstream part of the reforming unit itself, for example, near the gas inlet. Good.
[0026]
In the reformer of the present invention,
The said reforming part shall be installed so that gas may flow horizontally.
[0027]
As a reformer for mounting on a fuel cell vehicle or the like, a horizontal installation type is adopted because of the limitation in the height direction in terms of vehicle mountability. In this horizontal installation type reformer, the condensate does not flow out due to gravity, so the condensate tends to stay in the reforming section. By applying the present invention to a horizontally installed reformer, the condensate can be removed quickly, so that the start-up time of the reformer can be shortened efficiently. Note that “horizontal” does not have to be exactly horizontal, and means horizontal enough to prevent the condensate from flowing out due to gravity.
[0028]
The present invention can be configured as an invention of a fuel cell system including a reforming device and a vehicle equipped with the fuel cell system, in addition to the above-described configuration as a reforming device. In addition, in each aspect, it is possible to apply the various additional elements shown above.
[0029]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in the following order based on examples.
A. Reformer:
B. Condensate removal and recovery:
C. Second embodiment:
D. Variations:
[0030]
A. Reformer:
FIG. 1 is an explanatory view showing the configuration of a reformer as a first embodiment of the present invention. The reformer 100 includes a raw material tank 10 for storing methanol, a water tank 20 for storing water, an evaporation unit 30 for evaporating methanol and water supplied from the raw material tank 10 and the water tank 20, and vaporized methanol. A reforming unit 40 for reforming by a reforming reaction and a CO oxidation unit 60 are provided. The CO oxidation unit 60 is for oxidizing the carbon monoxide that has passed through the reforming unit 40 without being converted into carbon dioxide by the reforming reaction into carbon dioxide.
[0031]
The methanol reforming reaction in the catalyst-supporting honeycomb 42 of the reforming unit 40 is performed at about 300 ° C. In the reforming apparatus 100 of the present embodiment, in addition to heating from a heater (not shown) for raising the temperature of the reforming unit 40 at the time of start-up, the exothermic action of the reactions shown in equations (4) and (5) shown above is used. It has been. In the initial stage of the warm-up operation of the reforming apparatus 100, since the temperature of the reforming unit 40 is low, the methanol and water vaporized in the evaporation unit 30 are condensed. This condensate prevents the temperature of the reforming unit 40 from rising. The reformer 40 is provided with a condensate removing means for removing the condensate. In addition, a recovery means for recovering the condensate is also provided upstream of the reforming unit 40. Condensate removal means and recovery means will be described later.
[0032]
B. Condensate removal and recovery:
FIG. 2 is an explanatory view showing a condensate removing unit and a collecting unit. FIG. 3 is an explanatory diagram showing details of the A portion in which an ellipse is marked in FIG. As shown in the figure, the reforming apparatus 100 of the present embodiment is a horizontally installed apparatus in which gas flows horizontally in the reforming unit 40. The reforming unit 40 has a structure in which the periphery of a cylindrical catalyst-supporting honeycomb 42 supporting a Cu—Zn base metal catalyst is covered with a metal case 144 using the alumina mat 52 as a buffer material. The surface of the alumina mat 52 is coated with a polytetrafluoroethylene (PTFE) dispersion (hereinafter, this coating is referred to as PTFE coating). The PTFE coating 53 has heat resistance and has a property of repelling the condensate, and functions as a condensate removing means. Thereby, it is possible to prevent the condensate from penetrating into the alumina mat 52. The PTFE coating 53 does not need to be applied to the entire surface of the alumina mat 52, and may be applied to only a part thereof.
[0033]
Condensation is likely to occur upstream of the reforming unit 40. Then, the condensate repelled by the PTFE coating 53 moves downward by gravity and oozes out from the A part. On the upstream side of the reforming unit 40, a drain 54 is provided as a collecting means for collecting the condensate. The condensate recovered from the drain 54 can be reused as a reforming material. The reforming unit 40 may be installed with an inclination so that the upstream side is lower than the downstream side. By doing so, the condensate generated in the reforming unit 40 can easily flow into the drain 54 on the upstream side.
[0034]
Thus, according to the first embodiment, the PTFE dispersion that repels the condensate is coated on the alumina mat 52 that is the buffer material between the catalyst-supporting honeycomb 42 and the case 44, so that the condensate can be quickly removed. Can do. As a result, the loss of heat energy consumed for vaporizing the condensate can be reduced, and the temperature of the reforming section can be increased efficiently. As a result, the start-up time of the reformer 100 can be shortened. In addition, since unreformed methanol gas can be prevented from flowing downstream of the reforming unit 40, adverse effects on subsequent processes can also be suppressed.
[0035]
C. Second embodiment:
In the first embodiment, the PTFE coating 53 applied to the alumina mat 52 is used as the condensate removing means. In the second embodiment, a PTFE mat is used instead as a cushioning material. The other configuration is the same as that of the first embodiment.
[0036]
According to the second embodiment, since the PTFE mat 52A is used as the buffer material, the condensate can be repelled and quickly removed. As a result, the start-up time of the reformer 100 can be shortened. In addition, since unreformed methanol gas can be prevented from flowing to the downstream side of the reforming section 40, adverse effects on subsequent processes can be suppressed.
[0037]
D. Variations:
As mentioned above, although several embodiment of this invention was described, this invention is not limited to such embodiment at all, and implementation in various aspects is possible within the range which does not deviate from the summary. It is. For example, the following modifications are possible.
[0038]
D1. Modification 1:
In the above embodiment, the buffer material (including the surface treatment) having the property of repelling the condensate in the reforming part is used as the condensate removal means, but the present invention is not limited to this. In general, the present invention removes the condensate generated in the reforming section. For example, the reforming section may be rotated at high speed around the gas flow direction and the condensate may be removed by centrifugal force.
[0039]
D2. Modification 2:
In the above embodiment, polytetrafluoroethylene having heat resistance and a property of repelling the condensate is used for the condensate removing means, but other materials may be used depending on the required heat-resistant temperature.
[0040]
D3. Modification 3:
In the above embodiment, the drain 54 for recovering the condensate is provided in the upstream pipe of the reforming unit 40, but it may be provided in the upstream part of the reforming unit 40 itself. FIG. 4 is an explanatory view showing a condensate removing unit and a collecting unit of a reformer as a modification. In this modified example, ring-shaped PTFE mats 52Aa to 52Ae are disposed in the upstream portion as a cushioning material so as to have a gap, and the PTFE mat 52Af is disposed in the downstream portion. The case 44A is provided with drains 54a to 54e at positions corresponding to the gaps between the PTFE mats 52Aa to 52Af. The rest is the same as the above embodiment. By doing so, the condensate produced in the reforming unit 40 can be removed from the gaps between the PTFE mats 52Aa to 52Af and can be recovered from the drains 54a to 54e. In this modification, the condensate is removed from the gap between the PTFE mats 52Aa to 52Af. For example, the condensate is removed from the through hole using a PTFE mat having a through hole instead of the gap. You may do it.
[0041]
D4. Modification 4:
In the above-described embodiment, the horizontal installation type reformer including the condensate removing unit has been described. However, the vertical installation type reformer may include the condensate removing unit.
[0042]
D5. Modification 5:
Although the reforming apparatus has been described in the above embodiment, it can be configured as a fuel cell system including the reforming apparatus of the present invention. Moreover, it can also be comprised as invention of the vehicle carrying this.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram showing a configuration of a reformer as a first embodiment of the present invention.
FIG. 2 is an explanatory view showing a condensate removing unit and a collecting unit.
FIG. 3 is an explanatory diagram showing details of an A portion in which an ellipse is marked in FIG. 2;
FIG. 4 is an explanatory view showing a condensate removal means and a recovery means of a reformer as a modification.
FIG. 5 is an explanatory view showing a reformer of the reformer.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 ... Raw material tank 20 ... Water tank 30 ... Evaporating part 40 ... Reforming part 42 ... Catalyst carrying honeycomb 44, 44A ... Case 52A, 52Aa-52Af ... PTFE mat 54, 54a-54e ... Drain 100 ... Reforming apparatus 142 ... Catalyst Supporting honeycomb 144 ... Case 152 ... Alumina mat

Claims (5)

A reformer for generating hydrogen gas from a liquid raw material containing a hydrocarbon compound ,
An evaporation section for evaporating the liquid material;
A reforming section for generating hydrogen gas from the evaporated raw material by a reforming reaction;
At least the condensate removing means for removing the condensate condensed in the reforming section,
With
The reforming unit includes a unit carrying a reforming catalyst, a case covering the unit, and a cushioning material provided between the unit and the case,
The condensate removing means is means for removing the condensate from at least the buffer material,
Reformer. The reformer according to claim 1,
The condensate removing means is means for flipping the condensate,
Reformer. The reformer according to claim 1,
Furthermore, a recovery means for recovering the removed condensate is provided.
Reformer. The reformer according to claim 3 , wherein
The recovery means is provided on the upstream side of the reforming unit,
Reformer. The reformer according to claim 1,
The reformer is installed so that gas flows horizontally,
Reformer.

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