Degradation kinetics of aromatic VOCs polluted wastewater by functional bacteria at laboratory scale

Abstract

Reaction kinetics in biodegradation process is the basis and key of bioremediation technology, which can be used to predict the interaction between microorganisms and environmental states in the system. In this study, the kinetic model (Monod, Moser, Tessier and Cotonis) and kinetic parameters of aerobic biodegradation of functional bacteria in simulated wastewater polluted by aromatic volatile organic compounds (VOCs) were determined by shaking flask experiment. Monod, Moser, Tessier and Contois models were used to fit the experimental data and determine the kinetic parameters based on nonlinear regression analysis. Experimental results demonstrated that the removal rate of aromatic VOCs at 72 h was between 34.78 and 99.75% depending on the initial concentration of aromatic VOCs. The specific growth rate μ and degradation rate q increased with the increase of substrate concentration. The model of Monod, Moser and Tessier could be used to simulate microbial growth and substrate degradation in simulated aromatic VOCs polluted wastewater. Then the model and corresponding kinetic parameters were used to predict the limit concentration of biodegradation and provide theoretical support for the subsequent dynamic simulation and field engineering.