Process for preventing the formation of black spots on the walls of underground water reservoirs

摘要

A method for preventing the formation of black marks on the walls of sunken pools containing water contaminated by copper ions, which consists in treating the water using an effective amount of a metal sulfide having a water solubility at least equal to the solubility of copper sulfide. The treatment reduces the concentration of copper ions in the water and prevents the formation of black marks on the walls.