Nutrient Removal: On-Line Measurements and Control Strategies

Abstract

New control strategy principles with respect to nitrogen and phosphorus removal in activated sludge plants are described. The principles include control of phase length and oxygen set point based on criteria functions and continuous on-line measurements of ammonium, nitrate, phosphate and pH. Five case studies are stated which describe improvements in biological nitrogen and phosphorus removal and in chemical phosphorus removal at activated sludge plants ranging from 5000 to 220000 population equivalents (0.25 to 11 MGD). The improvements due to the new strategies are basically a reduction of nutrients in the effluent and a reduction in the amount of chemicals and electricity consumed.

Wastewater Treatment Systems: Modelling, Diagnosis and Control

“…This includes the BioDenitro and Bio-Denipho processes (Lynggaard & Nielsen, 1993), (Thornberg et al , 1993), (Önnerth et al , 1996), (Nielsen &Önnerth, 1996), (Zhao et al , 1994b), (Zhao et al , 1994a), (Bundgaard, 1988), (Thornberg, 1988), (Sørensen et al , 1994) and (Nielsen et al , 1981).…”

Instrumentation, Control and Automation in Wastewater Systems

“…More on the control of the BioDenitro TM / BioDenipho® processes can be found in Nielsen (1983); Thornberg et al (1993);Sorensen et al (1994); Nielsen and Ønnerth, (1995) and Potter et al (1996). Nielsen and Ønnerth (1995) and Ønnerth et al (1996) controlled the aeration to a recirculating plant in an intermittent way, which significantly improved the plant performance.…”

Instrumentation, control and automation in the water industry – state-of-the-art and new challenges

“…The importance of the DO profile in space and aeration control in plug-flow type reactors was recognized early (Olsson and Andrews, 1978). For intermittently aerated systems, the control of the aerobic phase-length has been studied intensively (Nielsen, 1983;Thornberg et al, 1993;Sorensen et al, 1994;Nielsen and Ønnerth, 1995;Potter et al, 1996).…”