Process Design Considerations for Industrial Wastewater Treatment Using SBR Technology to Achieve Biological Nitrogen Removal and EC Control

A sequencing batch reactor (SBR) activated sludge system was designed to upgrade an industrial wastewater treatment facility serving multiple industries at Tulare, California. The purpose of the upgrade was to provide capacity to meet more stringent effluent quality criteria for discharge/reuse and to provide expansion from 26,000 m3/d (7 MGD) to a total of 45,000 m3/d (12 MGD). Particular emphasis was placed on meeting an electrical conductivity (EC) discharge limit of 500 uS/cm above background groundwater conditions. The design approach sought to make optimum use of existing processes and included continued use of an existing low rate anaerobic reactor and existing aerated lagoons for pretreatment prior to additional COD removal and nitrification and denitrification in the SBR process. The system currently (2009) is under construction with completion scheduled for late 2009.