Removal of Toxicants from Leather Industrial Wastewater Using Sawdust Filter Media and Ferric Oxide Coagulant

Abstract

The leather industrial wastewaters are a major source of water pollution among all industrial sector considering both quantity and composition. This research study was focused on the current chemical and physical parameters of tannery wastewater and treatment processes through sawdust filter media and ferric oxide (Fe2O3) coagulant. The study found that tannery wastewater contained exceptionally high values of TDS, TSS, TS, BOD, COD, SO42-, Cl-, Na, Ca, chromium, lead, cadmium and arsenic and theses parameters of the composite were exceeded the standard discharge limits which are considered as toxicants for the environment. The wastewaters were filtered by saw-dust filtration processes and then treated with different dosage of Fe2O3. The experiment elucidated that the filtration technique could minimize certain amount of toxicant load from the wastewater but not efficient enough to practise the technique alone using as wastewater treatment. The chemical interaction with 100 mg/L coagulant (Fe2O3) dosage at pH~9 showed the best result of the major parameters. The study suggested that both combined physical (filtration) and chemical (Fe2O3, coagulants) treatment processes could be fruitful to reduce the toxicants load from tannery wastewater.