Controlling the aeration volume of the aerator is a significant energy-saving method for the microporous aeration head system. When dissolved air (DO) is used as an indicator, the power can be saved by 33%. According to the relationship between the air volume of the fan and the energy consumption, it can be known that the power consumption varies greatly with the air volume, so the energy saving effect of the air volume control is significant, and the greater the power, the more obvious the effect.
Of course, the gas volume cannot be arbitrarily reduced, it will be affected by many factors.
From the perspective of the treatment process, the diaphragm aerator system must be controlled, because if the tube aerator system is not operated properly, the aeration amount is too small, and the secondary sedimentation tank may be sludge decay due to lack of oxygen, that is, the tank The bottom sludge is anaerobic decomposed, and the aeration head generates a large amount of gas, which promotes the sludge to float. When the aeration time is long or the aeration amount is too large, high nitrification will occur in the aeration tank, so that the nitrate concentration in the mixed liquid is high. At this time, a large amount of N2 or NH3 may be generated in the sedimentation tank due to denitrification, and the sludge will float up. In addition, whether the distribution of the aeration of the disc aerator is balanced and stable is also an important reason that affects the treatment effect and energy consumption. During the operation of the aeration system, due to various interferences, the distribution of the aeration volume of the aeration plate will change. These will make the biological response unbalanced and reduce the quality of treatment. In order to achieve the treatment effect, the aeration amount has to be adjusted, and the change of the dissolved oxygen at a certain point at this time cannot accurately reflect the treatment state of the biological pool, so that the control using the dissolved oxygen as an indicator becomes unstable and energy consumption increases.
Analysis and conclusion
The characteristics of the underwater diffuser aerator system are as follows:
1) The amount of sewage input is a random variable, and its external environment has many uncertain factors, so it is difficult to establish accurate mathematical models of aerated biological systems;
2) The parameter dimension of the microporous aerator system is high, strong coupling, and highly nonlinear;
3) There is a large time lag in dissolved oxygen, and it is difficult to achieve system equilibrium in a short time;
4) The practical experience and knowledge of a large number of skilled operators are required in the wastewater treatment process;
5) Stable and uniform distribution of aeration flow is the basis for controlling treatment effect and energy saving. Therefore, solving the aeration system control should be improved from two aspects, one is to solve the balance and stability of the air flow in the aeration tank, and the other is to find a suitable control strategy for the dissolved oxygen to control the air flow.