ABSTRACT
Flow measurement at wastewater treatment facilities is essential for plant operation and process control. The average and diurnal variations in flow are needed to determine how much chemicals to add, how much air to supply into the aeration basins, and how much sludge to return into the biological reactors. This chapter discusses various types of flow-measuring devices. It presents step-by-step design procedure, details, and specifications for a Venturi meter in the design example. The chapter shows the comparision of the operating characteristics of flow-measuring devices when installed at various locations at a wastewater treatment facility. The accuracy and repeatability and range of applicability are extremely important criteria for selection of a flow measurement device. Most modem flow measurement devices have an indicator, a recorder, an on-line integrator mechanism, and/or computer that enables the daily volume to be read off directly, thus eliminating the tedious job of manually integrating the data on the recorder chart.
