| With the increament of the world wide environmental protection pressure, China also gives more pressure to pulp & paper industry for environment & management. Wastewater treatment becomes a focus for every pulp & paper company. As a major treatment way, biological treatment can make a lot of wastewater reuse or discharge standards, is increasingly being used by the pulp and paper companies. Once the biological treatment process is determined, whether the system can working in efficient, low consumption, stable state, the key lies in their process control. A good process control can handle the running costs of the system to play with the highest operating efficiency.Characteristics of pulp and paper wastewater pollution can be different because of their pulp and paper process and section, but they still have common characteristics, which are very different with municipal sewage's pollution characteristics. This determines the biological treatment of pulp and paper effluent is unique. Seeing from the performance of its operating costs, lies in three main areas: adjusting the pH at the anaerobic system with the addition of acid and alkali; the power consumption of artificial aeration at aerobic process to control the dissolved oxygen(DO) and the cost of addition of N and P nutrients at aerobic process.In this paper, the control of these three studies carried out, mainly to do the following work:1) A pH control system is established with the actual pulp and paper wastewater anaerobic treatment system in Shandong as the background. A mathematical model of pH regulation system is established and the formation of a pH adjusting with fuzzy PID control system is designed. Simulation using MATLAB was carried out to compare the PID control, fuzzy control and fuzzy PID control of the step response and interference response. Conclusion is that the performance of fuzzy PID control is the best.2) A DO control system is also established with the actual pulp and paper wastewater aerobic treatment system in Shandong as the background. A mathematical model of DO aeration system is established. The Fuzzy PID system for DO control is designed. MATLAB simulation was carried out to compare the PID control, fuzzy control and fuzzy PID control of the step response. The conclusion is that Fuzzy PID control synthesises of fuzzy integral role in regulation and that it can meet the rapid response to requirements at the same time to be no overshoot.3) With White Birch Paper Company of Canada Pulp and paper mill activated sludge aerobic wastewater treatment system for the background, the N, P nutrients dosage control system for pulp and paper aerobic wastewater treatment is researched. At first, a pulp and paper mill wastewater sludge ASM1-PP model is designed basing on the activated sludge ASMl mathematical model introduced by IAWQ (International Association Water Quality), with appropriate modifications conside to the characteristics of pulp and paper wastewater pollution. By adding the influence of N, P nutrient concentrations on microbial to the mathematical model, it is suitable for activated sludge aerobic wastewater treatment system of the pulp and paper mill.Then, Simulation and Calibration of ASM1-PP model are maded using the GPS-X wastewater treatment simulation software designed by Canadian Hydromantis. During the simulation work, the literature data obtained by the process is used. Finally, an instance of wastewater treatment system simulation model is setted up with the calibrated ASM1-PP model as the biological treatment center. A simulation study on the N, P nutrient dosage is maded, in order to find some of the law of its control system.4) The optimum control algorithm and control law is applied to an instance of the process control system. Designed a set of pulp and paper wastewater biological treatment process control system, in which the Fuzzy PID algorithms are used in the process of pH in anaerobic and DO in aerobic processes control; and a system based on expert control of N, P dosing is designed, using some of the rules getted by the N, P dosage simulation...
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