title: Nitrogen removal in a SBR using the OGAR process control system.
abstract: OGAR is an industrial process control system that utilises on-line redox measurements to control the aeration sequence in an activated sludge process. Compared to conventional process control systems that use dissolved oxygen, OGAR makes use of redox as a control parameter during both aerobic and anoxic conditions. This paper reports on its first application in a sequencing batch reactor. The principal aim of this project is to demonstrate the capability of OGAR to achieve concentrations of total nitrogen in the treated effluent of less than 10 mg/L, which are typically stipulated by Queensland's Environmental Protection Agency (EPA). In this study the use of the control system resulted in the following SBR performance: consistent effluent total nitrogen less than 5.0 mg/L; ammonia concentration reduced from 31.6 mg/L to 0.32 mg/L, effluent nitrate 2.8 mg/L; DO setpoint 1.5 mg/L had 10% higher effluent total nitrogen compared to DO setpoint 4.0 mg/L and redox end-points for nitrification 400 mV, denitrification 150 mV.
mesh_terms: D000641:Ammonia / Q000032:analysis; D001420:Bacteria, Aerobic / Q000502:physiology; D019149:Bioreactors; D009584:Nitrogen / Q000737:chemistry / Q000302:isolation & purification*; D010084:Oxidation-Reduction; D010100:Oxygen; D014865:Waste Disposal, Fluid / Q000379:methods*
chemical_list: D000641:Ammonia; D009584:Nitrogen; D010100:Oxygen