Characteristic Analysis Of Pollutants In Municipal Wastewater Treatment Plant Of Guiyang

With the development of rapid process of urbanization in ourcountry, there is a dramatic increase in the content of wastewaterand the sewage sludge. At the same time the wastewater and the sewagesludge impact on the environment has been carried on enthusiasticlyby scholars at home and abroad. There is abundant nutrition in thesewage sludge, so the utilization of sewage sludge on land has beenconsidered as an active and effective method for the disposal.However, there are many potential pollutants in sludge haveecological risk. To system evaluation the potential ecological risk,we began the research of pollutants in wastewater and sewage sludge,expectation providing scientific reference and resource use of thesludge. Six wastewater treatment plants in Guiyang were select, andthe results of pollutants in the wastewater and sewage sludge areas follows:1) Through the analysis of pollution in the wastewater of thesix wastewater treatment plants in Guiyang we found that, after thetreatment the pollutions in the effluent of wastewater are becomelow. The content of ammonia nitrogen, total phosphorus and COD inthe wastewater is lower than the ational primary standard B; thesix kinds of heavy metals likes Pb, Cr, Cd, Cu, Hg, As and the organicpollutions likes OCPs, PAEs in the effluent are both lower than the limit of national standards.2)Organic matters in the sewage sludge of Guiyang is lower thanpig mature, but the average of total nitrogen and total phosphorusin sewage sludge is higher, with the content is about18.25g/kgand10.54g/kg, respectively. The average content of heavy metalssuch as Zn, Cu, Pb, Cr, As, Cd, Hg in sewage sludge is about670.66mg/kg,121.09mg/kg,40.57mg/kg,23.81mg/kg,8.76mg/kg,2.71mg/kg and1.28mg/kg, respectively. The content of heavy metalsare lower than the studies of our country expect Hg and compare withthe limit of heavy metals in China sewage sludge only Cd of S3wastewater plant is overran. The average content of organicpollution likes∑PAEs,∑OCPs,∑PAHs and volatile phenol is54.456mg/kg,26.283μg/kg,177.565μg/kg,1.001mg/kg,respectively. The organic pollutions are lower than the studies ofour country，expect the∑PAEs．3)To evaluate the safety of use of sludge on land, thegeoaccumulation index, Nemerow pollution index and potentialecological risk index is applied．The results show that: Thepollution of heavy metal Zn，Cu and Hg are serious, the potentialecological risk of heavy metal of Cd, Hg are both high. At the sametime the OP′-DDT, hexachlorobenzene, anthracene and naphthalenein the sewage sludge should cause our great concern.