Electrochemical Methods for Purification of Waste Waters

Abstract

Publisher Summary This chapter discusses the electrochemical methods for purification of waste waters. The purification of waste waters must always be carried out to such a degree that the corresponding lawful norms be satisfied; only then the purified water can be discharged into the surroundings. All processes for waste water treatment are expensive and cause an increase of manufacturing costs and of prices. The treatment of waste waters is in the focus of interest of the whole society, hence legislative provisions and their checking are necessary. Modern approach to purification of waste waters containing heavy metal or other substances assumes that water of a certain provenience is supplied that must be freed from a particular metal or compound. The pH value can be adjusted after mixing together all charges of waste water purified separately. Such an approach permits the isolation of a metal or a sufficiently pure compound suitable to be reused in production. The classical method of purification of all waste water charges mixed together and containing many heavy metal ions by the addition of lime ensured low concentrations of these ions in the discharged water, however the side product was sludge containing heavy metal hydroxides and lime, which was deposited on dumps.