Influence of Organic Loading Rates (OLR) in Treatment of Pulp and Paper Mill Wastewater with Hybrid Upflow Anaerobic Sludge Blanket Reactor (HUASBR) with Hexagonal Polypropylene Inert Material

Abstract The present work illustrates the effective treatment of raw pulp and paper mill effluent using a model hybrid upflow anaerobic sludge blanket reactor (HUASBR). The physico-chemical and biological characteristics of wastewater were observed to be critical from the pollution potential aspect. The design features of model HUASBR had a respective total and effective working capacity of 7.5 and 6.5l, together with 25 cm depth of packing by polypropylene hexagonal inert material at the top of the reactor. Start-up of the reactor was carried out using an inoculum mixture containing rumen liquid of goat and cow dung slurry at an appropriate ratio of 3 : 1(v/v). Also, the reactor was effectively started up at the end of 36 days. Based on the performance of model HUASBR, under the respective variations of organic loading rates (OLRs) of 1, 2 and 4 kg COD m −3 d −1 , the stepwise COD removals were found to be about 41, 69 and 87%. However, a hydraulic loading rate (HRT) of 20 h was appropriately maintained throughout the studies.