Constant Flow Water Production System Design Based On PLC

MBR (Membrane Biological Reactor), also known as membrane bioreactor, is akind of membrane bio-processing technology used in sewage treatment, mainlyconsisting of membrane separation technology and biological wastewater treatmenttechnology. MBR mainly includes the bioreactor and the membrane module. Thepolluted water is purified after the degradation of organic matter in the bioreactormicroorganism. Membrane traps activated sludge, organic molecules and bacteria inthe reactor, while the purified water filters through the membrane group. And thewater reaches quality requirements. At the same time, the MBR membrane can assurea high concentration of sludge in bioreactor to accelerate the biological response.MBR membrane cell entraps the active sludge by the filtering function, thusincreasing the concentration of sludge to enhance biological effect. MBR pool wateris sent over by the pump. The effluent is linked by pump and membrane system intank. The depression sucks so that the clean water is pumped out through themembrane and the sludge is truncated out of the membrane to stay in the pool.Compared with conventional activated sludge process, the MBR takes advantages ofeasy management, small footprint, and stability of water quality.According to the technical requirements of the system, design principle andengineering actual situation, the constant flow of water producing system isintroduced in detail the overall design scheme, and presents a design scheme ofcommunication network. On the basis of the detailed design, the paper introduces thechoice of each hardware unit under the constant flow water production system of amachine, man-machine interface software design.From the automation perspective, we can’t establish an automatic controlalgorithm that is applied to all membrane processing due to the effect of sewageconcentration, temperature, membrane level, MBR membrane permeability and aseries of external condition. Traditional PID strategy is widely used in controllingmembrane pool water production constant flow while it’s very effective in traditionallinear time-invariant system. But in the practical application, the traditional PIDstrategy’s drawbacks include excessive overshoot and long regulation time. And itcan’t reach the requirements in control processes. The controlling effect of traditionalPID algorithm and adaptive fuzzy PID algorithm are analyzed from the theoreticalperspective. By comparing the Matlab simulations of these two algorithms, the adaptive fuzzy PID algorithm behaves better and reaches better controlling effect thanthe traditional PID algorithm in the controlling constant flow.