Collaborative Operating Optimization Of Reserve Osmosis, Ozone And Chlorination For Reclaimed Water Treatment

Accoring to the system optimization, mathematical statistics and water treatment theories, the study practiced lots of experiments via the ozone pilot test device and the reverse osmosis-ozone-chlorination system whose scale reaches 72m3/d. By studying the effect of chlorination, ozone oxidation and reverse osmosis on decolorization and residual chlorine retention for reclaimed water, the study reaches the rule that how temperature affects ozone’s treatment ability of decolorization and sterilization,guiding the actual production of ozone for water recycling plant. And it puts forward collaborative operation scheme optimization of reverse osmosis-ozone-chlorination system, ensuring the treatment effect, reducing operating costs to achieve economic efficiency. Besides it proposes an expansion plan for water recycling plant which makes the expansion and operation cost optimization.Firstly, the study takes the ozone pilot test to analysis the influence of ozone’s treatment ability of decolorization and sterilization by temperature, then uses the reverse osmosis-ozone-chlorination system to test the results. The results show that when above zero degree, the effect of ozone decolorization is better with the temperature increases until reaching the optimal point, and vice versa. And when the water quality is worse, the best temperature of decolorization is lower. Also, the ozone sterilization is not conducive to conduct under high temperature.Secondly, the study builds the decolorization’s and sterilization’s mathematical model of reverse osmosis-ozone-chlorination system, and proposes its collaborative optimization operation strategy, establishing the optimization model. According to the different water treatment scale and raw water quality, the study designs the bset dosage of chlorine and ozone and blending ratio, reducing the operation cost. To compare the best operating conditions and the actual operating conditions, ensuring the water quality of effluent, the operation cost can be reduced from 8.40% to 17.28%and the economic benefit is very obvious.Finally, based on the above research, the study determines that the water recycling plant must be expanded to ensure the water quality of effluent when its long-term scale of 100000 tons reaches. So three kinds of expansion plan are put forward, using optimize model calculation and annual cost method to select theoptimal scheme. The scheme is to increase two reverse osmosis equipment(Siemens BW365FR), which expansion cost is five million yuan, the annual operating cost is4.8856 million yuan and the average annual cost is about 5.435 million yuan.