Abstract

Most surface waters contain varying amounts of suspended solids, including silt, clay, bacteria, viruses, etc. It is necessary to remove these prior to distribution to domestic or industrial customers. Abundant supplies of fresh water are essential to the development of industry. Enormous quantities are required for the cooling of products and equipment, for process needs, for boiler feed, and for sanitary and potable water supply. Sedimentation and filtration are the principal treatment processes for both municipal and industrial water. These are discussed in detail. Also discussed is the removal of colloidal particles by coagulation and flocculation. Lime and lime-soda processes, and ion exchange are used to control hardness of water. Data on taste and odor control methods, as well as removal of organic compounds, nitrates, arsenic, and radionuclides iron and manganese, which impact on potable water quality, are given. This article also gives details on the various impurities found in water and how the water is treated to make it acceptable for industrial use. Clarification, precipitation, settling, filtration, ion exchange, and membrane processes are all detailed. Particular attention is given to corrosion control in boilers. Condensate systems can be chemically treated to reduce metal corrosion, especially important in cooling systems. Types of corrosion, eg, pitting, galvanic corrosion, are discussed. Deposit accumulations in cooling systems, biofouling and microfouling organisms are also summarized.