Wastewater Treatment Plants

Book excerpt: Step-by-step procedures for planning, design, construction and operation: * Health and environment * Process improvements * Stormwater and combined sewer control and treatment * Effluent disposal and reuse * Biosolids disposal and reuse * On-site treatment and disposal of small flows * Wastewater treatment plants should be designed so that the effluent standards and reuse objectives, and biosolids regulations can be met with reasonable ease and cost. The design should incorporate flexibility for dealing with seasonal changes, as well as long-term changes in wastewater quality and future regulations. Good planning and design, therefore, must be based on five major steps: characterization of the raw wastewater quality and effluent, pre-design studies to develop alternative processes and selection of final process train, detailed design of the selected alternative, contraction, and operation and maintenance of the completed facility. Engineers, scientists, and financial analysts must utilize principles from a wide range of disciplines: engineering, chemistry, microbiology, geology, architecture, and economics to carry out the responsibilities of designing a wastewater treatment plant. The objective of this book is to present the technical and nontechnical issues that are most commonly addressed in the planning and design reports for wastewater treatment facilities prepared by practicing engineers. Topics discussed include facility planning, process description, process selection logic, mass balance calculations, design calculations, and concepts for equipment sizing. Theory, design, operation and maintenance, trouble shooting, equipment selection and specifications are integrated for each treatment process. Thus delineation of such information for use by students and practicing engineers is the main purpose of this book.