| 摘要 |
PROBLEM TO BE SOLVED: To provide an off-gas recycle system for a fuel cell power-generating device of such a structure as recycling the off-gas exhausted from a fuel electrode of fuel cell and feeding back to the fuel electrode upon being mixed with a fuel gas (aux. type hydrogen) supplied anew externally, with which it is precticable to suppress the accumulation of the concentration of a minute quantity of impurities other than hydrogen included in the fuel gas in association with the off-gas recycling and permit the fuel cell to operate in a stable performance for a long period of time. SOLUTION: An off-gas recycle circuit 4 is installed in piping between a gas outlet of a fuel electrode 1a of a fuel cell 1 and an ejector pump 3 installed in a fuel gas supply circuit 2, and to this recycle circuit 4a gas purge line 7 opened to the atmosphere side is installed divergently on the way of the pipeline, and through it a part of off-gas to be recycled is discharged to outside the system via the gas purge line. This allows suppressing the accumulation of a minute quantity of impurities included in the fuel gas in the system in the course of repeated recycles, and thereby battery performance can be maintained stably. |
