+ Resolve Article
+ Follow Us
Follow on FacebookFollow on Facebook
Follow on TwitterFollow on Twitter

+ Translate
+ Subscribe to Site Feed
GeoScience Most Shared ContentMost Shared Content

Feedback control of activated sludge waste rate

, : Feedback control of activated sludge waste rate. Journal Water Pollution Control Federation 60(11): 1979-1985

An algorithm for feedback control of activated sludge waste rate has been developed. It uses proportional-integral-derivative (PID) control with waste flow rate as the manipulated parameter and an unsteady-state calculations of sludge age (the dynamic sludge age, or DSA) as the process variable. PID control can be implemented either on-line using sensors and automatic control, or off-line using lab results and manual implementation of computed control action. Both methods were studied using computer simulations. Feedback control reduced the error in DSA by 60% for a step change in setpoint, and 80% for a step change in influent biochemical oxygen demand (BOD), as compared to no control (constant waste flow rate). For a realistic forcing function consisting of 6 months of influent flow and BOD data, the variability of the DSA was reduced by 22% by continuous PID control, and 14% by off-line control. Improved DSA control resulted in increased variability in system biomass.


DOI: 10.2307/25046848

Other references

Mesquita, E.Tinoco.; Souza Júnior,; Ferreira, T.Reigado.; Vesalius, A., 2016: Andreas Vesalius 500 years--A Renaissance that revolutionized cardiovascular knowledge. The history of medicine and cardiology is marked by some geniuses who dared in thinking, research, teaching and transmitting scientific knowledge, and the Italian Andreas Vesalius one of these brilliant masters. His main scientific work "De H...

Joos S.K., 1979: Diet obesity and diabetes mellitus among the florida seminole. Florida Scientist 42(SUPPL 1):

Hulbert, I.A.R.; Wyllie, J.T.B.; Waterhouse, A.; French, J.; Mcnulty, D., 1998: A note on the circadian rhythm and feeding behaviour of sheep fitted with a lightweight GPS collar. The circadian rhythm and feeding behaviour (bite rate) of 16 Scottish Blackface ewes of which eight were fitted with a lightweight (863 g) GPS collar were examined. The collar consisted of a leather harness and a 0.5 l aluminium box and represente...

Wilson, Clare, 2013: Does banning prostitution make women safer?. Sex industry researcher Laura Agust n has spent 20 years investigating sex trafficking. She says most of what we think we know about it is wrong.

Zhuchenko, A.A., 1988: Adaptive potential of crop plants: ecological and genetic principles. In an examination of adaptive potential as a function of the interaction of genetic systems for ontogenetic and phylogenetic adaptation, aspects of the genetic control and mechanisms of ontogenetic adaptation (including resistance to stresses) are...

Stott, P., 2007: Chronic disease--another challenge for the developing world. International Journal of Clinical Practice 61(9): 1422-1423

Weingaertner, L., 1963: Basic Remarks On Drug Injuries In Childhood. Die Medizinische Welt 37: 1848-1852

D.V.s, K.J.; Allan, V.J.; Grierson, A.J.; Sheetz, M.P., 2005: Mitochondrial function and actin regulate dynamin-related protein 1-dependent mitochondrial fission. Mitochondria display a variety of shapes, ranging from small and spherical or the classical tubular shape to extended networks [1, 2]. Shape transitions occur frequently and include fusion, fission, and branching [3]. It was reported that some mit...

Hwang S.F.; Howard R.J.; Moskaluk E., 1989: Crown and root rot of alfalfa in southern alberta canada. Twenty-seven alfalfa [Medicago sativa] fields in southern Alberta were surveyed in 1983 for the incidence and severity of crown and root rot disease. Mean disease incidence and severity were 61% and 0.80 (on a scale of 0-3), respectively. Four spe...

Ball, Ea, 1974: Experimental observations on the living shoot apex. Revue de cytologie et de biologie vegetales: 7 (3 4) 353-369