Control Of Wastewater Treatment Systems Research Articles

Performance evaluation and modeling of a submerged membrane bioreactor treating combined municipal and industrial wastewater using radial basis function artificial neural networks.

Treatment process models are efficient tools to assure proper operation and better control of wastewater treatment systems. The current research was an effort to evaluate performance of a submerged membrane bioreactor (SMBR) treating combined municipal and industrial wastewater and to simulate effluent quality parameters of the SMBR using a radial basis function artificial neural network (RBFANN). The results showed that the treatment efficiencies increase and hydraulic retention time (HRT) decreases for combined wastewater compared with municipal and industrial wastewaters. The BOD, COD, {mathrm{NH}}_4^{+}-mathrm{N} and total phosphorous (TP) removal efficiencies for combined wastewater at HRT of 7 hours were 96.9%, 96%, 96.7% and 92%, respectively. As desirable criteria for treating wastewater, the TBOD/TP ratio increased, the BOD and COD concentrations decreased to 700 and 1000 mg/L, respectively and the BOD/COD ratio was about 0.5 for combined wastewater. The training procedures of the RBFANN models were successful for all predicted components. The train and test models showed an almost perfect match between the experimental and predicted values of effluent BOD, COD, {mathrm{NH}}_4^{+}-mathrm{N} and TP. The coefficient of determination (R2) values were higher than 0.98 and root mean squared error (RMSE) values did not exceed 7% for train and test models.

Model Predictive Controller for Integrated Wastewater Treatment System

Optimising control of wastewater treatment systems (WWTS), allowing for cost savings while fulfilling the effluent discharge limits over long period requires application of advanced control techniques. Model Predictive Control (MPC) is a very suitable control technology for a synthesis such a truly multivariable controller that can handle constraints and accommodate model-based knowledge combined with hard measurements. A hierarchical architecture is used to structure the MPC controller into the functional Supervisory, Optimising and Follow up levels. The Optimising Control Level is further decomposed into three layers operating in different time scales: slow, medium and fast. The paper considers MPC controller operating in medium time scale.As it is impossible to efficiently control the plant under all possible influent conditions, three dedicated control strategies were designed. The controller performance was validated by simulation based on Kartuzy WWTS data records. Recently developed mechanism for soft switching between different MPC control strategies was used in the simulations.

Monitoring and control using on-line orp on the continuous-flow activated sludge batch reactor system

On-line monitoring of ORP has been proved to be a practical and useful technique for process control of wastewater treatment systems. This paper presents the feasibility of using on-line ORP monitoring system on a laboratory scale single tank continuous-flow activated sludge batch reactor, which is capable of removing carbon, nitrogen and phosphorus pollutants. Two control strategies, fixed-time and real-time, are applied for process control. Results obtained from fixed-time control study indicate that the variations and the ORP profile can accurately represent dynamic characteristics of system; the pH profile can also indicate some of those characteristics. Also, the breakpoints, setpoints and settime on the ORP and pH profiles are used to establish the real-time control strategy to determine the transfer of operation stages. The real-time experiments show a better performance than fixed-time, thus, on-line ORP and pH monitoring and control is practical for continuous-flow batch activated sludge process control.

Monitoring and control using on-line ORP on the continuous-flow activated sludge batch reactor system

On-line monitoring of ORP has been proved to be a practical and useful technique for process control of wastewater treatment systems. This paper presents the feasibility of using on-line ORP monitoring system on a laboratory scale single tank continuous-flow activated sludge batch reactor, which is capable of removing carbon, nitrogen and phosphorus pollutants. Two control strategies, fixed-time and real-time, are applied for process control. Results obtained from fixed-time control study indicate that the variations and the ORP profile can accurately represent dynamic characteristics of system; the pH profile can also indicate some of those characteristics. Also, the breakpoints, setpoints and settime on the ORP and pH profiles are used to establish the real-time control strategy to determine the transfer of operation stages. The real-time experiments show a better performance than fixed-time, thus, on-line ORP and pH monitoring and control is practical for continuous-flow batch activated sludge process control.

Optimization of wastewater treatment plant systems

Water Environment ResearchVolume 64, Issue 4 p. 400-402 Wastewater TreatmentFree Access Optimization of wastewater treatment plant systems Dennis D. Truax, Dennis D. TruaxSearch for more papers by this author Dennis D. Truax, Dennis D. TruaxSearch for more papers by this author First published: 01 June 1992 https://doi.org/10.1002/j.1554-7531.1992.tb00017.xAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. REFERENCES Baier, U., and Zweifelhofer, H. P. (1991) Effects of Aerobic Thermophilic Pretreatment. Water Environ. Technol., 3, 1, 56. Chaudbary, R., et al. (1991) Evaluation of Chemical Addition. Water Environ. Technol., 3, 66. Faller, J. A., and Ryder, R. A. (1991) Clarification and Filtration to Meet Low Turbidity Reclaimed Water Standards. Water Environ. Technol., 3, 68. Govind, R., et al. (1991) Fate and Effects of Semivolatile Organic Pollutants During Anaerobic Digestion of Sludge. Water Res. (G. B.), 25, 54. Grau, P. (1991) Criteria for Nutrient-balanced Operation of Activated Sludge Process. Water Sci. Technol. (G. B.), 24, 251. Harlan, W. (1991) Continuous and Versatile Process Control. Oper. Forum, 8, 6, 32. Laukkanen, R., and Pursiainen, J. (1991) Rule-based Expert Systems in the Control of Wastewater Treatment Systems. Proc. 2nd Int. Conf. Syst. Anal. Water Qual. Manage., Durham, N.H., 299. Lettinga, G., et al. (1991) Future Perspectives for the Anaerobic Treatment of Forest Industry Wastewater. Water Sci. Technol. (G. B.), 24, 91. Mininni, G., et al. (1991) Cost Optimization of Sewage Sludge Filter-pressing. Water Sci. Technol. (G. B.), 23, 201. Mobius, C. H. (1991) Nitrogen and Phosphorus Limits for Nutrient Deficient Industrial Wastewaters. Water Sci. Technol. (G. B.), 24, 258. Odendall, P. E. (1991) Wastewater Reclamation Technologies and Monitoring Techniques. Water Sci. Technol. (G. B.), 24, 9, 173. Oosterlee, G. J. (1991) Process Automation of the Hague Sewage-Treatment Plant. J. Inst. Water Environ. Manage., 5, 134. Peterson, W. A. (1991) Operational Quality in Wastewater Management. Water Environ. Technol., 3, 50. Stover, E. L., and Campana, C. K. (1991) Computerized Biological Treatment Operational Process Control. Proc. 2nd Int. Conf. Syst. Anal. Water Qual. Manage., Durham, N. H., Publ. 323. von Sperling, M., and Lumbers, J. P. (1991) Optimization of the Operation of the Oxidation Ditch Process Incorporating a Dynamic Model. Water Sci. Technol. (G. B.), 24, 225. Walker, J. M. (1991) Fundamentals of Odor Control. BioCycle, 32, 9, 50. Volume64, Issue41992 Literature ReviewJune 1992Pages 400-402 ReferencesRelatedInformation

Control of wastewater treatment systems

Some basic ideas of process control applied to the activated sludge process are presented. The focus is rather on controller structures than on models. The reason for the control is due to disturbances and load chances. Due to the wide span of time scales of the process it is possible to realize many control actions decoupled from each other. Some of the controllers are quite simple and do not require any model, while others are related to quality parameters and are based on model descriptions. By combining simple controllers, more complex structures can be obtained, such as cascaded control and feedforward control. For some control tasks the simple controllers are inadequate. Processes with time-variable parameters present special problems. Since many variables and parameters are not directly measurable, it is valuable to apply estimation techniques in order to obtain indirectly calculated variables. The interdisciplinary character of the problems has to be understood in order to find relevant solutions to the complex control problems.

Rule-Based Expert Systems in the Control of Wastewater Treatment Systems

Rule-based expert systems create a low-cost solution to master all empirical knowledge available in existing wastewater treatment plants. Currently there exists no universal model for processes of biological wastewater treatment, while existing data records and human experience form, however, a valuable knowledge base for an enhanced understanding of process interrelations. In spite of the natural ambiguity of human reasoning and expression, final control policy can, nevertheless, be efficiently translated into on-line automation.