Development of Predictive Kinetic Models for the Biodegradation of Olusosun Dumpsite Leachate using Activated Sludge Process

Biodegradation of leachate generated from dumpsite before discharging to the environment is a way of preserving and sustaining the environment. The aim of this work was to develop kinetics for biodegradation of Olusosun dumpsite leachate in Lagos State using activated sludge process. Sludge of 2.5 L was seeded in a bioreactor and 25 L of collected leachate from Olusosun dumpsite was transferred into the bioreactor using a single stage centrifugal pump operated at 25 L/min. A retention time of 7 days was observed after which aeration was provided into the bioreactor and the content was stirred. Treated leachate sample were taken at hydraulic retention time (HRT) in variation between 2 and 14 hrs. The treated and untreated leachate samples were analysed for biochemical oxygen demand (BOD) and volatile suspended solids (VSS) according to standard methods for examination of water and wastewater prescribed by American Public Health Association/American Water Works Association /Water Environment Federation. The integrated form of the Monod and Modified Monod model were employed to determine the bio-kinetic coefficients which include maximum specific substrate utilization rate (K), half saturation coefficient (Ks), endogenous decay coefficient (Kd) and yield coefficient (Y). The bio-kinetic coefficients were then used to develop predictive kinetic models for bio-degradation of Olusosun dumpsite leachate. The results showed that the values of K, Ks, Kd and Y were 1.0246 hr-1, 27.001 mg/L, 0.0265 hr-1 and 0.269 mgVSS/mgBOD respectively. The developed predictive kinetic model can be used to navigate Olusosun dumpsite leachate biodegradation process using activated sludge.