Determination of kinetic coefficients for treating synthetic oily wastewater in suspended growth batch fed reactor

Discharge of oily wastewater imparts serious threat to the environment because of high level concentration of COD, BOD as well as oil and grease and it is difficult to treat such wastewater due to its inherent toxic and inhibitory property. A treatability study of oily wastewater (carrying petroleum) has been performed in the present work using a batch suspended growth reactor. The experiment was conducted using acclimatized suspended biomass in laboratory environment and the kinetic coefficients were determined which are immensely important for design of such reactor. The oil removal efficiency was observed to be in the range of 62.84-85.45% corresponding to average MLSS concentration range of 1,797-3,668 mg/L. Haldane kinetic model was found to be the best fitted for the biodegradation of oily wastewater with acclimatised microorganisms in the present investigation. The kinetic co-efficients including K-s, Y, k(d), k and k(i) were calculated from the experimental data and the values were compared with published results cited by various scientists. The derived kinetic coefficients values are to be useful for understanding the dynamics of substrate utilisation with production of biomass and efficient design of biological systems and also for pilot plant investigation with real life wastewater of similar nature.

Automated summary

The discharge of oily wastewater poses a serious threat to the environment, and it is difficult to treat due to high COD, BOD, oil, and grease concentrations. A study was conducted using a batch suspended growth reactor, showing oil removal efficiency in the range of 62.84-85.45%, with the Haldane kinetic model as the best fit for biodegradation. The derived kinetic coefficients are useful for understanding substrate utilisation dynamics and designing efficient biological systems.