ON-LINE CONSTRUCTION AND RULE BASE SIMPLIFICATION BY REPLACEMENT IN FUZZY SYSTEMS APPLIED TO A WASTEWATER TREATMENT PLANT

Optimization of wastewater treatment plants with extensive phosphorus and nitrogen removal is complicated. The Klagshamn wastewater treatment plant in Sweden is operated with pre-precipitation of phosphorus with ferric chloride and denitrification with methanol as carbon source. An activated sludge process, operated with pre-precipitation and denitrification with external carbon source in a compartmentalized plant, requires only small tank volumes but increases the need for proper operation and optimization. On-line nitrogen, ammonia, and TOC sensors are used for a day-to-day control and optimization while mathematical modelling is used for long term strategic planning. The on-line measurements are further used as the basis for the modelling. TOC and ammonia sensors at the influent clearly identify typical and extreme loading variations and nitrate measurements in the activated sludge tanks and the effluent shows the dynamics of the processes. These measurements provide a basis for model calibration. In combination low residuals of nitrogen, phosphorus and organic matter can be achieved.

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Respirometry-based on-line model parameter estimation at a full-scale WWTP

Water Science & Technology ◽

10.2166/wst.2002.0619 ◽

2002 ◽

Vol 45 (4-5) ◽

pp. 335-343 ◽

Cited By ~ 2

Author(s):

H. Spanjers ◽

G.G. Patry ◽

K.J. Keesman

Keyword(s):

Wastewater Treatment ◽

Parameter Estimation ◽

Activated Sludge ◽

Wastewater Treatment Plant ◽

Treatment Plant ◽

Parameter Estimates ◽

Model Parameter ◽

Model Parameter Estimation ◽

On Line ◽

Set Up

This paper describes part of a project to develop a systematic approach to knowledge extraction from on-line respirometric measurements in support of wastewater treatment plant control and operation. The paper deals with the following issues: (1) test of the implementation of an automatic set-up consisting of a continuous laboratory respirometer integrated in a mobile trailer with sampling and dosing equipment, and data-acquisition and communication system; (2) assessment of activated sludge/sewage characteristics from sludge respirograms by model parameter estimation; (3) comparison of the parameter estimates with regular plant data and information obtained from supplementary wastewater respirograms. The paper describes the equipment and some of its measuring results from a period of one week at a large-scale wastewater treatment plant. The measurements were evaluated in terms of the common activated sludge modelling practice. The automatic set-up allowed reliable measurements during at least one week. The data were used to calibrate two different version of the model, and independent parameter estimates were obtained.

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Nitrate estimation in the denitrifying post-filtration unit of a municipal wastewater treatment plant: the Viikinmäki case

Water Science & Technology ◽

10.2166/wst.2012.038 ◽

2012 ◽

Vol 65 (8) ◽

pp. 1521-1529 ◽

Cited By ~ 2

Author(s):

M. Mulas ◽

F. Corona ◽

H. Haimi ◽

L. Sundell ◽

M. Heinonen ◽

...

Keyword(s):

Wastewater Treatment ◽

Wastewater Treatment Plant ◽

Municipal Wastewater ◽

Linear Models ◽

Treatment Plant ◽

Municipal Wastewater Treatment ◽

Soft Sensors ◽

Intrinsic Nonlinearity ◽

On Line ◽

Filtration Unit

In this work we present and discuss the design of an array of soft-sensors to estimate the nitrate concentration in the denitrifying post-filtration unit at the Viikinmäki wastewater treatment plant in Helsinki (Finland). The developed sensors aim at supporting the existing hardware analyzers by providing a reliable back-up system in case of malfunction of the instruments. In the attempt to design easy to implement and interpretable sensors, computationally light linear models have been considered. However, due to the intrinsic nonlinearity of the process, also nonlinear but still computationally affordable models have been considered for comparison. The experimental results demonstrate the potential of the developed soft-sensors and the possibility for an on-line implementation in the plant's control system as alternative monitoring devices.

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On-Line Extraction of Fuzzy rules in a Wastewater Treatment Plant

IFIP International Federation for Information Processing - Artificial Intelligence Applications and Innovations ◽

10.1007/1-4020-8151-0_9 ◽

2006 ◽

pp. 87-101

Author(s):

J. Victor Ramos ◽

C. Gonçalves ◽

A. Dourado

Keyword(s):

Wastewater Treatment ◽

Wastewater Treatment Plant ◽

Treatment Plant ◽

Fuzzy Rules ◽

Line Extraction ◽

On Line

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Validation and implementation of model based control strategies at an industrial wastewater treatment plant

Water Science & Technology ◽

10.2166/wst.2001.0764 ◽

2001 ◽

Vol 44 (2-3) ◽

pp. 145-154 ◽

Cited By ~ 4

Author(s):

D. Demey ◽

B. Vanderhaegen ◽

H. Vanhooren ◽

J. Liessens ◽

L. Van Eyck ◽

...

Keyword(s):

Wastewater Treatment ◽

Wastewater Treatment Plant ◽

Industrial Wastewater ◽

Dynamic Models ◽

Control Strategies ◽

Treatment Plant ◽

Practical Implementation ◽

Industrial Wastewater Treatment ◽

Model Based ◽

On Line

In this paper, the practical implementation and validation of advanced control strategies, designed using model based techniques, at an industrial wastewater treatment plant is demonstrated. The plant under study is treating the wastewater of a large pharmaceutical production facility. The process characteristics of the wastewater treatment were quantified by means of tracer tests, intensive measurement campaigns and the use of on-line sensors. In parallel, a dynamical model of the complete wastewater plant was developed according to the specific kinetic characteristics of the sludge and the highly varying composition of the industrial wastewater. Based on real-time data and dynamic models, control strategies for the equalisation system, the polymer dosing and phosphorus addition were established. The control strategies are being integrated in the existing SCADA system combining traditional PLC technology with robust PC based control calculations. The use of intelligent control in wastewater treatment offers a wide spectrum of possibilities to upgrade existing plants, to increase the capacity of the plant and to eliminate peaks. This can result in a more stable and secure overall performance and, finally, in cost savings. The use of on-line sensors has a potential not only for monitoring concentrations, but also for manipulating flows and concentrations. This way the performance of the plant can be secured.

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