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Chemically enhanced primary treatment by adding coagulant to the wastewater can effectively remove the pollutants in the water, you can also chemically enhanced primary treatment to reduce the the two processing load, to improve the treatment effect. In recent years, the chemically enhanced primary treatment technology has gradually attracted the attention of the water treatment sector, to become a new hotspot. Coagulation enhanced primary treatment developed rapidly, but the dosage determination and coagulation sludge treatment and disposal problems hindering its marketing obstacles. FeCl3 because of its low price and good results, has been widely applied to the enhanced primary treatment of sewage. FeCl3 mechanism of Municipal Wastewater Treatment This issue through laboratory beaker test, research FeCl3 pretreatment effect in sewage treatment, optimal dosage and comparative analysis of the iron coagulation sludge and biological sludge performance of anaerobic digestion, the iron salts sludge anaerobic treatment effect. FeCl3 coagulation for phosphorus removal when iron salts dosage, stirring intensity effect on the removal of phosphorus; within the range of pH 6-8 has good phosphorus removal; PAM phosphorus removal helpful, but not obvious, comprehensive economic considerations, PAM is not suitable for a large number of dosing. Iron salts precipitate phosphorus removal analysis and XRD analysis showed that, when Fe: P is high (for example, 2.0, 2.5), sediment hydroxy iron phosphate and FeOOH (s); Fe: P lower , the main precipitate FePO4 based. Precipitate spectroscopy analysis showed that when high doses of iron salt dosing when iron and phosphorus molar ratio is much higher than 1, resulting in a waste of iron salts. Iron salts pretreatment process, the establishment of a neural network can be based on the degree of control the water, easily adjust the dosage to achieve water quality standards at the same time, reduce the total operating costs, enhanced primary treatment for iron salts chemical real-time The control provides a viable idea. To establish a three-layer BP neural network, hidden layers of 5-14, the training error is selected as 0.001, network training step 1000, the learning rate is chosen to be 0.1. The final choice of the hidden layers of 12 BP neural network training error of 0.0092. Trained neural network has good predictive SS removal rate predicted value and the actual value of the average relative error of 11.2%, COD average relative error to 8.39%, TP and P043-average relative error of 9.92% and 8.99%, respectively . Sewage-specific, the use of the trained model, can be easily selected according to the purpose of removal of iron salt dosage. Renewed through anaerobic test, comparative analysis of iron coagulation sludge and biological sludge anaerobic digestion performance results show that coagulation sludge and biological sludge can produce good digestion, produce has a cogeneration The value of biogas, VS degradation rate reached 26% and 29%, respectively, digested sludge VS the size downward trend, is conducive to subsequent processing. The study found that the iron sludge biogas accumulation rate is slow, this is because the iron salt dosing the floc wrapped part of the organic matter, so that the same load conditions, anaerobic digestion initial gas production than the biological sludge less.
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