| 摘要 |
PROBLEM TO BE SOLVED: To easily maintain, at a specified concentration, the residual chlorine concentration of a body of treatment target water having been subjected to a cleaning treatment.SOLUTION: Within a cleaning apparatus 10 of subterranean water, first sodium hypochlorite addition means 22 adds sodium hypochlorite to a body of treatment target water 18 for removing impurities included therein. An activated carbon column 40, furthermore, is used for removing residual chlorine included within the treatment target water 18 based on the permeation therethrough of the treatment target water 18. Second sodium hypochlorite addition means 42, furthermore, adds sodium hypochlorite to the treatment target water 18 for setting the residual chlorine concentration therein at a specified concentration. Even while impurities included within the treatment target water 18 are being removed by the first sodium hypochlorite addition means 22, therefore, the residual chlorine concentration of the treatment target water 18 can be controlled by the activated carbon column 40 and second sodium hypochlorite addition means 42, and it becomes possible to easily maintain, at a specified concentration, the residual chlorine concentration of the treatment target water 18 following the cleaning thereof. |
