The Research On Enhanced Coagulation Technology Treats Micro-polluted Water

In recent years ,because of the fast development of economy , sources water in the world have been widely polluted, the traditional water purification technique can not eliminate such contamination in the raw water. Therefore, the purification technique for the micro-polluted raw water has been an important and urgent research subject.Enhanced coagulation can raise the water fluid matter validly. Normal coagulation aim to get rid of the turbidity degree, but enhanced coagulation can do away with not only but also organic matter and NH₄⁺-N, controlling coagulation condition to increase the rate of organic matter and NH₄⁺-N. Doing away with the organic matter of the deliquescence is to adsorb metals sediments. Enhanced coagulation is to dose surfeit coagulant, new coagulant or other doses in normal crafts, and to control pH to strengthen coagulation which can increase the rate of organic matter, biggest limit do away with disinfect the vice- outcome ex- body thing, assurance drinking water disinfect the vice-outcome match the drinking water of the method of the standard.The study imitated water purification plants to carry on enhanced coagulation treatments on micro-polluted raw water, analyzing water quality parameters and full-scale experiment study including PFS,AS,PAFS,PAC and PASS in order to select the fittest coagulation to micro-polluted raw water.Enhanced coagulation's effect factors are: flocculant's category,the dose,pH value,the result of mixing,temprature and so on. The result of enhanced coagulation shows that the best condition is: PASS's dose is 8mg/L,mixing speed 280r/min, mixing time30s, flocculating speed 75r/min, flocculating time 30min, sedimentation time 30min, controlling pH 6.5～7.0. controling temperature above 15℃.While satisfies the water leakage water quality,reduces coagulation the amount used,reduces the cost. The key point is this experimental coagulation partial research. The experiment indicated that, coagulation will carry on duplicate matches not only can enhance the coagulation effect,more over will be able to reduce the cost. Under this test condition compound coagulation best throws the dose is:Gathers the PASS,PAC and PAM duplicate matches: (6.4+1.6+0.2)mg/L, Organic matter's rate is 80.8%, NH₄⁺-N's is 69.3%; Gathers the PASS,AS and PAM (5.4+3.6+0.2)mg/L, Organic matter's rate is 79.2%, NH₄⁺-N's is 70.2%.By the second coagulation, Gathers the PASS and PAC duplicate matches 2mg/L more, Organic matter's rate is 88.3%, NH₄⁺-N's is 76.3%; Gathers the PASS and AS 2mg/L more, Organic matter's rate is 87.5%, NH₄⁺-N's is 77.8%.The experiment indicated that, enhanced coagulation is a way to enhance the output water. On the based routine treatment aechnique, enhanced coagulation is efficient way to treat the micro-polluted raw water.