Heavy metal inhibition/toxicity control in anaerobic treatment process

In this study, inhibitory effects of some heavy metals on the anaerobic treatment systems according to production of methane were investigated. For this, increasing concentrations of different heavy metal ions in synthetic wastewater was treated by batch and continuous (UASB) mesophilic anaerobic reactors. All experiments were repeated under the same conditions by treating synthetic wastewater without adding metal ions.By using Logistic and Gompertz models, kinetic models of microbial growth, the total methane production (ml) and methane production rate (?max) was calculated. The results of the experiments showed close agreement with the values calculated in models.The highest concentration of heavy metals applied in the study is limited to 2 mM. According to these models, the values of methane production rate for the highest heavy metal concentration were in the following order: Cu> Zn> Ni> Cr> Pb> Cd.