Hazardous materials, heavy metals, and organic toxins released into the environment have caused considerable harm to microbes, plants, animals, and humans. Wastewater is one of the most contaminated ecosystems due to heavy metals emitted mostly by human activity. Bioremediation of wastewater is an ecologically acceptable and cost-effective method of removing heavy metals from sewage; the general purpose of this study is to analyse the dependability of anaerobic sludge biomass in removing sulfur compounds and heavy metals from waste water. The anaerobic sludge biomass evaluated in this work was taken from a wastewater treatment plant (WWTP) in Al-Rustumiya, Baghdad, and grown in the mineral medium for anaerobic growth. In serum bottles, batch metal removal tests were conducted concurrently with sulphate reduction. The biomass increased from the time of inoculation medium with 20 mg·L-1 (t = 0 day, MLVSS = 688 29 mg·L-1) to the 8th day, when it reached the highest value (MLVSS = 980 48 mg·L-1); more than 90% removal was observed for copper and nickel, almost 80% for lead and cadmium metals, and less than 80% removal for chrome and zinc. In addition, in the case of lead, copper, and nickel, sulphate removal was greater than 50%. Except zinc, all metals have the capacity to remove more than 60% of the COD.
