Wastewater treatment is usually characterized as consisting of four sequential processes: preliminary, primary, secondary and tertiary treatment. This publication will introduce you to processes and equipment for primary treatment of wastewater. You will be introduced to descriptions, functions and design considerations for sedimentation tanks and clarifiers, chemical precipitation, and Imhoff tanks. You will learn how the primary treatment processes works together with the preliminary, secondary, tertiary and sludge handling processes to form a complete wastewater treatment plant.About the Author: Paul Guyer is a registered civil engineer, mechanical engineer, fire protection engineer, and architect with over 35 years experience in the design of buildings and related infrastructure. For an additional 9 years he was a principal advisor to the California Legislature on infrastructure and capital outlay issues. He is a graduate of Stanford University and has held numerous national, state and local offices with the American Society of Civil Engineers, Architectural Engineering Institute and National Society of Professional Engineers.