A study on microbiology of biological film layer in rotating biological contactors

Experimental studies were carried out for upgrading the secondary treated domestic sewage effluent using the Rotating Biological Contactors (RBC);ss an unit process in the premises of the existing water reclamation plant of Satellite Centre Building Complex of Indian Space Research Organisation at Bangalore. As part of these studies, a brief study was carried out on the microbiological aspects of the biological slime layer developed in the RBC. This study included observations on the development of the biological film on wetted disc surfaces of RBC, measurement of the thickness of the biological film, a discussion on significance of biofilm thickness in substrate removal, effect of wastewater characteristics on the thickness of biofilm and determination of MLSS/MLVSS ratio of biological film obtained in RBC reactor used for upgrading the secondary effluent. The results of these studies are presented in this paper The results of identification of species of micro-organisms predominant in the biological slime layer in the RBC used for upgradation of secondary treated effluent are discussed separately in another paper.