Optimizing denitrification of City of Austin's Walnut Creek wastewater treatment plant

Abstract

Abstract The purpose of this project was to explore ways to optimize denitrification at City of Austin’s Walnut Creek Wastewater Treatment Plant (WWTP), by ensuring good denitrification all year while maintaining a low effluent ammonia concentration. Another aim was to seek ways to keep high alkalinity through the treatment process to maintain good pH control. The experiments were conducted using laboratory scale reactors fed with wastewater from the WWTP. The project used standardized methods to determine chemical and biochemical oxygen demand (COD, BOD), total nitrogen, nitrate, and ammonia. Other methods include trend measurements of nitrate, dissolved oxygen (DO), and pH; titrating to determine the wastewater’s alkalinity; and making chemical solutions It was discovered that denitrification was happening in reactor 3 with 67% nitrogen removal. The significance of the solids retention time (SRT) for denitrification was established: longer is better. Unusual COD/BOD ratios were discovered as COD