| This thesis introduces the actuality of Bailonggang WWTP which adopts chemically enhanced primary treatment (C EPT), and analysises the main pollutants in the effluent of high rate clarification tank. SS and TP have reached the discharge stantard and ammonia is the main pollutant which can not reach the discharge standard.Considering the present situation of Bailonggang wwtp and all kinds of proper wastewater treatment processes,ZBAF(zeolite biological aerated filter) was proposed to be the secondary process of the high rate clarification.This thesis has mainly studied on the feasibility of ZBAF as the secondary biological process, and has done laboratory study of two kinds of general BAF which adopt foamed EPS and expanded shale as filtration media and bio-contact oxidation process at the same time.The study indicates: in winter and in summer, the concentration of ammonia and COD in effluent of ZBAF can reach the discharge standard with HRTl.lh. The removal efficiency of ammonia of the pilot-scale ZBAF is much better than all other laboratory experiment. The zeolite in the filter is not only as media, but also as ammonia buffer,which is beneficial to impactive ammonia loading.This thesis has also studied on the ammonia-adorption and anti-attrited capability of the zeolite which has been as media in ZBAF for one year. |
