Physicochemical Treatment Consisting of Chemical Coagulation, Precipitation, Sedimentation, and Flotation

This publication is a collection of a few authors’ lecture materials of the Lenox Institute of Water Technology (LIWT) where the authors taught advanced humanitarian engineering courses and provided graduate education to international students around the world totally free of charge for decades. This publication has been timely assembled in memory of coauthors Professor Nazih K. Shammas and Professor Hermann H. Hahn without sufficient preparation time. Some omissions or repetitions among the authors’ various publications are unavoidable. When a scholar leaves this world, he/she will be summarized as digital numbers and words, stored in the clouds, distributed through the Windows, and shown on the Internet. The scholar’s life continuously lives whenever his/her publication is cited by other scholars. The subjects covered in this memoir-style publication are: chemistry of chemical coagulation and precipitation, electrical potential of negatively charged colloidal particles, effects of inter-particle forces on the stability of colloidal systems, relative coagulation power of electrolytes, optimum pH values for metallic coagulants, types of coagulating and precipitating chemicals, plug flow reactors, completely mixed continuous flow reactors, theories and principles of solid–water separation, rapid mixing basin design, flocculator design, sedimentation clarifier design, flotation clarifier design, streaming current monitor, and recent advances in partial or complete physicochemical process systems (PCPS) including chemical feeding, mixing, precipitation, coagulation, flocculation, clarification, filtration and disinfection. Design and applications of PCPS for wastewater and water treatment are introduced. The authors also introduce the US Environmental Protection Agency (USEPA) expected PCPS pretreatment results for treating the wastewaters from aluminum foundry die casting industry, metal finishing industry, iron and steel industry, textile mills, stream electric industry, inorganic chemical industry, ore mining and dressing industry, porcelain industry, paint manufacturing industry, coil coating industry, nonferrous metals industry, aluminum forming industry, battery industry, electrical and electronic industry, copper industry, organic chemical industry, auto industry, and laundries. Also introduced are: (a) the applications of dissolved air flotation (DAF) clarification for replacing sedimentation clarification under certain engineering conditions, and (b) the availability of commercial DAF facilities (Supracell, Sandfloat, Sedifloat, Clari-DAF, AquaDAF, etc.) for treating general industrial effluents, specific petrochemical wastewater, turkey farm wastewater, and municipal drinking water. The case histories reported in this publication can be applied to any manufacturer’s process equipment in any shape (rectangular or circular shape).