Hydrogen generation apparatus, fuel cell system, and hydrogen generation apparatus operation method

1. A hydrogen generation apparatus comprising:

a reformer operative to generate a hydrogen-containing gas by using a raw material gas;

a first desulfurizer operative to remove, through adsorption, a sulfur compound in the raw material gas that is to be supplied to the reformer;

a second desulfurizer operative to hydrodesulfurize a sulfur compound in the raw material gas that is to be supplied to the reformer;

a first passage through which the raw material gas is supplied to the reformer through the first desulfurizer;

a second passage through which the raw material gas is supplied to the reformer through the second desulfurizer, without passing through the first desulfurizer;

a switch operative to switch a passage through which the raw material gas flows between the first passage and the second passage; and

a controller including processing circuitry and a memory storing a program,

wherein the program, when executed by the processing circuitry, causes the controller to control the switch such that the raw material gas flows through the first passage in at least one operation selected the group consisting of a pressure compensation operation and a raw material gas purge operation, the pressure compensation operation being an operation of supplying the raw material gas to the reformer in order to compensate for an internal pressure drop that occurs in the reformer after an operation of generating the hydrogen-containing gas is stopped, and the raw material gas purge operation being an operation of purging the inside of the reformer with the raw material gas.

2. The hydrogen generation apparatus according to claim 1 , comprising:

a first on-off valve provided on the first passage at a position downstream from the first desulfurizer; and

a second on-off valve provided on the first passage at a position upstream from the first desulfurizer, wherein

the controller opens the second on-off valve before opening the first on-off valve in at least one operation selected from the group consisting of the pressure compensation operation and the raw material gas purge operation.

3. The hydrogen generation apparatus according to claim 1 , comprising:

a third passage through which the hydrogen-containing gas that is sent out from the hydrogen generation apparatus is supplied to the second desulfurizer; and

a third on-off valve provided on the third passage, wherein

the controller closes the third on-off valve in at least one operation selected from the group consisting of the pressure compensation operation and the raw material gas purge operation.

4. A fuel cell system comprising:

the hydrogen generation apparatus according to claim 1 ; and

a fuel cell operative to generate electric power by using the hydrogen-containing gas that is supplied from the hydrogen generation apparatus.

5. An operation method of a hydrogen generation apparatus, the operation method comprising:

hydrodesulfurizing, by a second desulfurizer, a sulfur compound in a raw material gas that is to be supplied to a reformer;

generating, by the reformer, a hydrogen-containing gas by using the raw material gas, the sulfur compound of which has been hydrodesulfurized;

performing at least one operation selected from the group consisting of a pressure compensation operation and a raw material gas purge operation, the pressure compensation operation being an operation of supplying the raw material gas to the reformer in order to compensate for an internal pressure drop that occurs in the reformer after the generating of the hydrogen-containing gas is stopped, and the raw material gas purge operation being an operation of purging the inside of the reformer with the raw material gas; and

removing, through adsorption by a first desulfurizer, a sulfur compound in the raw material gas that is to be supplied to the reformer when performing at least one operation selected from the group consisting of the pressure compensation operation and the raw material gas purge operation.

6. The operation method according to claim 5 , comprising opening a second on-off valve provided on a first passage at a position upstream from the first desulfurizer and opening a first on-off valve provided on the first passage at a position downstream from the first desulfurizer when performing at least one operation selected from the group consisting of the pressure compensation operation and the raw material gas purge operation.

7. The operation method according to claim 5 , comprising closing a third on-off valve provided on a third passage used for supply to the second desulfurizer when performing at least one operation selected from the group consisting of the pressure compensation operation and the raw material gas purge operation.

8. A fuel cell system comprising:

the hydrogen generation apparatus according to claim 2 ; and

a fuel cell operative to generate electric power by using the hydrogen-containing gas that is supplied from the hydrogen generation apparatus.

9. A fuel cell system comprising:

the hydrogen generation apparatus according to claim 3 ; and

a fuel cell operative to generate electric power by using the hydrogen-containing gas that is supplied from the hydrogen generation apparatus.