Intelligent control method of blast aeration system of municipal sewage plant

Abstract

The invention provides an intelligent control method of a blast aeration system of a municipal sewage plant. The blast aeration system comprises aeration tanks, a dissolved oxygen tester, an air blower, an air supply header pipe and supply branch pipes, wherein a header pipe pressure gage and a header pipe air flow meter are arranged on the air supply header pipe, and a branch pipe air flow meter and a valve are arranged on each supply branch pipe. The intelligent control method is characterized in that a controller estimates current load by aid of a dissolved oxygen balancing model according to current dissolved oxygen concentration and change rate of each aeration tank, the needed air supply amount is estimated according to the estimated load and the current dissolved oxygen concentration, parameters of the air blower are adjusted so as to lead the total air supply amount of the air blower to be identical to the sum of the air supply amount needed by all the branch pipes, and simultaneously the opening degree of the valve arranged on each branch pipe can be adjusted so as to lead the air supply amount needed by all the aeration tanks to be identical to the flow amount fed back by the branch pipe air flow meter arranged on each branch pipe. The controller is used for gradually adjusting the parameters of the air blower so as to lead the largest opening degree of each branch pipe valve to be kept above the lowest set limit and further to lead pressure of the air supply header pipe to be the smallest.

Description

technical field [0001] The invention relates to a sewage treatment technology, in particular to an intelligent control method for an air blast aeration system in an activated sludge process in a city sewage plant. Background technique [0002] The activated sludge method is the most widely used treatment process in urban sewage treatment. The biological aerobic process of the aeration tank is the key link of the process. In this link, the activated sludge can use the dissolved oxygen (DO) in the water to degrade the sewage organic pollutants to purify sewage. [0003] Dissolved oxygen has an important influence on the degradation rate of pollutants and the growth process of activated sludge. It is an important process control parameter and an important factor determining the energy consumption of the system. Blast aeration is one of the common oxygenation methods. Since the influent load of the sewage plant is a dynamic process, it is necessary to adjust the blast aeration ...

AI Technical Summary

Problems solved by technology

However, when the dynamic change of the influent load is large, due to the hysteresis, nonlinearity, and time-varying characteristics of the mass transfer and consumption process of dissolved oxygen, the use of simple PID is easy to cause the oscillation of dissolved oxygen concentration, and the stability of the system is not high

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