Fundamental nonlinearities of the reactor-settler interaction in the activated sludge process
(2012) In Water Science and Technology 66(1). p.28-35- Abstract
- The activated sludge process can be modelled by ordinary and partial differential equations for the biological reactors and secondary settlers, respectively. Because of the complexity of such a system, simulation models are most often used to investigate them. However, simulation models cannot give general rules on how to control a complex nonlinear process. For a reduced-order model with only two components, soluble substrate and particulate biomass, general results on steady-state solutions have recently been obtained, such as existence, uniqueness and stability of solutions. The aim of the present paper is to utilize those results to formulate some implications of practical importance. In particular, strategies are described for the... (More)
- The activated sludge process can be modelled by ordinary and partial differential equations for the biological reactors and secondary settlers, respectively. Because of the complexity of such a system, simulation models are most often used to investigate them. However, simulation models cannot give general rules on how to control a complex nonlinear process. For a reduced-order model with only two components, soluble substrate and particulate biomass, general results on steady-state solutions have recently been obtained, such as existence, uniqueness and stability of solutions. The aim of the present paper is to utilize those results to formulate some implications of practical importance. In particular, strategies are described for the manual control of the effluent substrate concentration subject to the constraint that the settler is maintained in normal operation (with a sludge blanket in the thickening zone) in steady state. Such strategies contain how the two control parameters, the recycle and waste volumetric flow ratios, should be chosen for any (steady-state) values of the input variables. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/2859665
- author
- Diehl, Stefan LU and Farås, Sebastian LU
- organization
- publishing date
- 2012
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- Clarifier, Continuous sedimentation, Modelling, Partial differential equation, Thickener
- in
- Water Science and Technology
- volume
- 66
- issue
- 1
- pages
- 28 - 35
- publisher
- IWA Publishing
- external identifiers
-
- wos:000305296700005
- pmid:22678197
- scopus:84862627070
- pmid:22678197
- ISSN
- 0273-1223
- DOI
- 10.2166/wst.2012.162
- language
- English
- LU publication?
- yes
- id
- d0a2a102-3eb2-41c5-b546-84cc7f2f29b5 (old id 2859665)
- date added to LUP
- 2016-04-01 09:48:10
- date last changed
- 2022-01-25 08:47:45
@article{d0a2a102-3eb2-41c5-b546-84cc7f2f29b5, abstract = {{The activated sludge process can be modelled by ordinary and partial differential equations for the biological reactors and secondary settlers, respectively. Because of the complexity of such a system, simulation models are most often used to investigate them. However, simulation models cannot give general rules on how to control a complex nonlinear process. For a reduced-order model with only two components, soluble substrate and particulate biomass, general results on steady-state solutions have recently been obtained, such as existence, uniqueness and stability of solutions. The aim of the present paper is to utilize those results to formulate some implications of practical importance. In particular, strategies are described for the manual control of the effluent substrate concentration subject to the constraint that the settler is maintained in normal operation (with a sludge blanket in the thickening zone) in steady state. Such strategies contain how the two control parameters, the recycle and waste volumetric flow ratios, should be chosen for any (steady-state) values of the input variables.}}, author = {{Diehl, Stefan and Farås, Sebastian}}, issn = {{0273-1223}}, keywords = {{Clarifier; Continuous sedimentation; Modelling; Partial differential equation; Thickener}}, language = {{eng}}, number = {{1}}, pages = {{28--35}}, publisher = {{IWA Publishing}}, series = {{Water Science and Technology}}, title = {{Fundamental nonlinearities of the reactor-settler interaction in the activated sludge process}}, url = {{http://dx.doi.org/10.2166/wst.2012.162}}, doi = {{10.2166/wst.2012.162}}, volume = {{66}}, year = {{2012}}, }