Application And Study Of Orbal Oxidation Ditch In The Small Town Municipal Wastewater Treatment Plant

Water is the origin of life, creatures can live without water, it is very important for human especially, if human have no water that we can not survive. With the development of the society and the increase of the number of population, water environment is destroyed day by day, and the extent of the damage is more and more serious, sewage treatment become more and more important, wastewater treatment plant also arises at the historic moment, The normal operation of wastewater treatment plant become important. Orbal oxidation ditch is the Variant technology of oxidation ditch, as its small footprint, have no primary settling tank and low costs, so it is very useful in the small town,it has been used widely.This paper takes the one small town Wastewater treatment plant of Lvliang city as example, monitor it through its actual operation effect, COD、BOD5are all stable under requirements of grade A, their removal rates are86.52%、92.16%, with winter coming and low temperature, SS、NH3-N and TP can not achieve water standards, their average removal rates down to88%、80%and81%. SV is also high, the sludge loss extremely easily. Through the different sampling points of oxidation ditch to analysis, we can known that the Biological choose pool can remove some organic matter, phosphorus release reaction occurred, it is very important for the whole process, strengthen the denitrification and phosphorus effect. In order to improve sludge sedimentation performance, sludge will not loss, use flocculant, research its effect on SV and removal of each pollutants. Through throwing PAC and diatomite, make sure the optimal dosage of them were40mg/L and30mg/L,under the optimal dosage, the removal rates of COD、NH3-N、TP by PAC were36.67%、42.15%、73.86%, SV was35%; the removal rates of COD、NH3-N、TP by diatomite were43.52%、44.02%、71.24%, SV was36%. Through comparative and analysis of the two flocculant, makes diatomite as the Best flocculant in the end.After throwing comparative, to optimization debugging the DO and return sludge ratio, analysis the influence of the treatment effect by changing different values, make the DO of outer channel is0.3mg/L-0.4mg/L, the DO of inside channel is2mg/L, return sludge ratio is100%.After debugging for some times, continue to monitor Wastewater treatment plant for some times, the results show that effluent quality were improved than before, except NH3-N all can stable under requirements of Water GB18918-2002Grade A, and Yielding Water are steady. During the monitoring, the average effluent concentration of COD、NH3-N、TP、BOD5、SS were40.17mg/L、7.98mg/L、0.43mg/L、8.9mg/L、8.3mg/L, removal rates were88.6%、78.32%、88.75%、93.51%、93.34%, SV was34%, it is improved than before. According to the actual operation situation of Wastewater treatment plant, for some problems, this paper puts forward advice, hope that offer help for Normal operation of the Wastewater treatment plant.