| 摘要 |
PURPOSE:To prevent the corrosion and the deterioration of pipings and fittings, and to acquire a fuel cell of a high reliability, by making the filling rate of a metallic wool at the gas inlet side higher than that at the gas outlet side. CONSTITUTION:In a scrubber 4, metallic wools 5a to 5c to remove the phosphoric acid are filled to make the wool diameters from the wool 5a at the gas inlet side to the wool 5c at the gas outlet side smaller in order. Since the phosphoric acid is at a high temperature, it reacts instantly making a phosphate, which is accumulated over the metallic wool 5a. Because the diameter of the metallic wool 5a is about 1 mm, for example, the phosphate never closes off its porousness. On the other hand, since the diameter of the metallic wool 5b is about 0.5 mm, for example, the majority of the phosphate which is not removed at the wool 5a is removed there. Finally, the metallic wool 5c contacting to the metallic wool 5b has the smallest diameter, about 0.2 mm, for example, and the phosphate is removed there perfectly, and then the gas is exhausted from the outlet piping 6b. |
