Theoretical development of biofilm in hybrid growth sequencing batch reactor (HG-SBR) for degradation of phenol

A kinetic modeling based study was carried out to evaluate the development of biofilm in hybrid growth sequencing batch reactor (HG-SBR) for the treatment of phenol synthetic wastewater. The microorganisms from activated sludge were allowed to grow onto the surface of packing materials to improve the treatment performances. The overall evaluation of HG-SBR with different initial COD loading recorded above 90%, 66%, 59% for each reactor with GAC, bio-ring and rod-shaped AC, respectively. Rapid degradation (98% removal) recorded for GAC through the profile study with 200 mg/L initial concentration. The development of biofilm on GAC, bio-ring and rod-shaped AC were studied through the kinetic models. As a result of the calculations, First-order model, Stover-Kincannon model and Grau second-order model were applicable (correlation coefficient R2 > 0.9) to describe the development of biofilm. The biofilm develop on the packed fixed bed materials was homogeneous and the thickness was varied for each materials. High regression coefficient for the comparison between the experimental COD and predicted COD values were obtained. This result indicated the kinetic models applied are capable of describing role of biofilm in HG-SBR by simplified the laborious experimental data to convenient mathematical expression.