Chemical Unit Processes

Chemical processes used in wastewater treatment are designed to bring about a few form of change through means of chemical reactions. They are always used in conjunction along with physical unit operations and biological processes. In common, chemical unit processes have an inherent drawback compared to physical operations in which they are additive processes. That is to say, there is commonly a net increase in the dissolved constituents of the wastewater. This could be a significant factor if the wastewater is to be reused. This section elaborates the major chemical unit processes, involving chemical precipitation, disinfection, adsorption, dechlorination and other applications.