BIODEGRADATION OF RESORCINOL AND CATECHOL IN SEQUENTIAL BATCH REACTOR

Abstract

Resorcinol and catechol, the derivatives of phenol, are considered to be versatile raw materials in chemical industry. Because of high toxicity, high oxygen demand and low biodegradability, these compounds are considered as primary pollutants in wastewater. Resorcinol and catechol have high toxicity and solubility and they widely exist in the effluents of industries such as textile, paper, pulp, steel, petrochemical, petroleum refinery, rubber, dyes, plastics, pharmaceutical and so on. The present study deals with the modification in the conventional wastewater treatment for phenolic compounds i.e. resorcinol and catechol. Sequencing batch reactor (SBR) is a promising alternative among the other biological processes. S B R is time-based treatment process technology as compare to the conventional area-based activated sludge processes. This study is about the design, modeling and the laboratory scale research on the optimization of S B R for the biodegradation of resorcinol and catechol. The effect of operating parameters, namely mixed liquor suspended solids concentration (MLSS), ratio of aeration time to fill phase and the initial substrate loading were studied. The results revealed that the highest resorcinol removal efficiency obtained at optimum conditions for 50 mg/1 initial concentration was 85.82%. The Haldane substrate inhibition model was used to describe the biodegradation kinetics of caiecHoFin SBR. The experimental data we compared with the calculated data. The kinetic parameters like Q m, K s and Kj was also calculated for best fit curves. The control of the sludge bulking and excessive growth of filamentous bacteria is restricted by taking the precautionary steps such as sludge wasting. The settling characteristics were measured in terms of SVI and settleability curve. The filterability of the sludge was also estimated. The physicochemical characterization of excess sludge wasted was done to evaluate its utilization as a source of energy.