| 摘要 |
PURPOSE:To prevent pipes and devices from being corroded and deteriorated by passing an exhaust gas including phosphoric acid discharged from a cell through the inside of a scrubber charged with a metallic wool whose rate of reaction with phosphoric acid is quicker at the exit side than at the entrance side. CONSTITUTION:An exhaust gas including phosphoric acid discharged from a cell is put into a scrubber 4 through an entrance pipe 6a and forced to tough metallic wool 5a. The phosphoric acid reacts with the wool 5a to form a phosphate and is accumulated, but since the rate of reaction of the wool 5a is slow, a part of the phosphoric acid passes without reaction. The rate of reaction of wool 5b is quick so that the most of the phosphoric acid is eliminated. At the least stage, the phosphoric acid is completely eliminated by wool 5c with the quickest rate of reaction and is discharged form an exit pipe 6b. Accordingly, even if the flow of the phosphoric acid is constant, because of the difference in the rate of reaction, there is no pressure loss caused by blinding induced near the entrance. Therefore, pipes and devices arranged in the flow after the cell itself are prevented from being corroded and deteriorated. |
