| In recent years, with the increasing of pollution of water sources and the higher degree of eutrophication, the frequency and dimensions of the water blooms in fresh water lakes is more and more serious. Eutrophication is one of the most prominent water environmental problem in current, while phosphorus is the key factors to control eutrophication. This paper is to work on removing phosphorus from enhanced coagulation, investigates the effect of removing phosphorus from coagulation when dosage:pH, settling time, using of coagulant aid was added, also studies the effect of ferrous sulfate on removing different forms of phosphorus. In the same time the paper analysis the effect of water purification with the different Eco-Zeolite Heap under static conditions to purify water in the laboratory, also researches the affordability of reactor on different load of phosphorus pollution and water loading. Finally these two techniques are put into projects and its actual effect is testified, which provide strong supports for the technology of removing phosphorus form micro-polluted water. The main content of this paper covers the following:In the experiments of removing phosphorus from enhanced coagulation under the natural water, the PFAC, PAC, ferrous sulfate and PFS in the dosage were 12 mg/L,10 mg/L,8 mg/L and 10 mg/L, the total rate of removal phosphorus reached 72.34%,74.06%,76.91%and 72.45%. The most appropriate pH of PAFC, PAC, PFS and ferrous sulfate was respectively 7, 6,8 and 7. Settling time of PAFC, PAC, ferrous sulfate were 30 minute when they achieved the best effect of removing phosphorus, while the time of PFS was 20 minute. PAM has a good effect on coagulation, which is better than ferrous sulfate, PAFC, PAC and PFS obviously on coagulation and removing phosphorus, and the rate of removing phosphorus was increased by 16.71%,10.28%,17.22% respectively when PAM was added, while the rate of removing phosphorus was increased by 8.94% for ferrous sulfate when additional PAM was added. The rate of removing different forms of phosphorus in water for ferrous sulfate ordered from large to small was:orthophosphate> particulate phosphorus> condensation phosphorus.The A, B, sterility Eco-Zeolite Heap all have a good water purification capacity in the static state adsorption process, while the A-Eco-Zeolite Heap have a better effect than the B-Eco-Zeolite Heap and sterility Eco-Zeolite Heap for the detersive power in the long term water purification, the removal rate of COD, ammonia nitrogen, TN, TP achieved at:48.63%, 44.60%,48.93% and 55.89%. Basis on the former study in the laboratory, which applied the A-Eco-Zeolite Heap to a dynamic water purification process, the results show that changes in hydraulic loading, COD and TN removal have a greater impact; hydraulic load increases from 0.4 m3/m2·h to 3.2 m3/m2·h, the removal rate of COD and TN decreased by 42.01% and 16.33%, but there are not much effect with TP and ammonia nitrogen, the removal rate of ammonia nitrogen always has been maintained at about 20.07%, while the removal rate of TP has maintained at a high level about 73.00%. In the study we found that the reactor had stronger impact resistance with the increase TP of influent concentration, while the removal rate of TP always maintained at 90.05% or even more. Besides, the study showed that the microorganisms in the Eco-Zeolite Heap to removal phosphorus did not have a better function than their physical adsorption to removal phosphorus.The ferrous sulfate, which is put into demonstration project can continuously keep a good condition of effluent water quality. It has a high removal of TP, which the removal rate is currently more than 70.59%. Compared to removal COD,TN,TP, the Eco-zeolite Heap leaching system, which is to removal ammonia nitrogen receives a greater influence by external conditions during the actual project, while the ammonia nitrogen removal only maintain at about 22.64%, and the dephosphorization in the overall project can be maintained at more than 50.23%...
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