ABSTRACT Pulp and paper industry is responsible for large discharge of highly polluted effluents, which often be treated by biological treatment process. For biological treatment system, pH is an important environmental factor that can influence the activity of microorganisms. In general, the optimal pH for aerobic processes is around neutral pH (7_7.8) and for the anaerobic process is between 6.8_7.2. The control of pH is a difficult link in the biological treatment system due to its nonlinearity and large time-delay. Aiming at the difficult point in the pH control of the biological wastewater treatment system, a mathematical model of pH control is estab-lished in the essay. On this basis, a traditional PID control and a cascade control are adopted to carry out simulation and comparison with MATLAB. The results show that the cascade control has better comprehen-sive effect in terms of response speed, stability and disturbance resistance.
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nullJ. KANG, M. WANG and Z. XIAO, "Modeling and Control of pH in Pulp and Paper Wastewater Treatment Process," Journal of Water Resource and Protection, Vol. 1 No. 2, 2009, pp. 122-127. doi: 10.4236/jwarp.2009.12016.
 U. Tezel, E. Guven, T. H. Erguder, and G. N. Demirer, “Sequential (anaerobic/aerobi) biological treatment of dalaman SEKA pulp and paper industry effluent,” Waste Management, Vol. 21, pp. 717-724, 2001.
 X. F. Yang, “Wastewater treatment in pulp paper making sector,” Chemical Industry Press, Beijing, 2001.
 Biothane System International, Enclosure F: Aerobic Microbiology [M], 2006.
 Biothane System International, Enclosure F: Anaerobic Microbiology [M], 2006.
 “An expert system for monitoring and diagnosis of anaerobic wastewater treatment plants,” Water Research, Vol. 36, pp. 2656-2666, 2002.
 S. B. Wu, “Water pollution control and treatment technology in the paper industry,” Chemical Industry Press, Beijing, Vol. 5, 2001.
 J. F. Bieteaua, “Modelling of anaerobic digestion in a fluidised bed with a view to control,” Biochemical Engineering Journal, Vol. 24, pp. 255-267, 2005.
 G. Ulvsson and B.Newell, “The model building, diagnosis and control of the wastewater treatment system,” Chemical Industry Press, Beijing, 2004.
 J. C. Wang and H. Y. Zhu, “Chemical process control [M],” Chemical Industry Press, Beijing, 1991.
 S. Regunath and V. Kadirkamanathan, “Design of a pH control system using fuzzy non-uniform grid scheduling and evolutionary programming,” Applied Soft Computing, pp. 91-104, 2001.
 W. W. Tan, F. Lu, A. P. Loh, and K. C. Tan, “Modeling and control of a pilot pH plant using genetic algorithm,” Engineering Applications of Artificial Intelligence, Vol. 18, pp. 485-494, 2005.
 R. A. Wright and C. Kravaris, “On-line identification and nonlinear control of an industrial pH process,” Journal of Process Control, Vol. 11, pp. 361-374, 2005.
 H. H. Lee and J. W. Yang, “A new method to control electrolytes pH by circulation system in electrokinetic soil remediation,” Journal of Hazardous Materials B77, pp. 227-240, 2000.