Increasing environmental awareness coupled with more stringent regulation standards has triggered various industries to challenge themselves in seeking appropriate wastewater treatment technologies. Coagulation–flocculation process is regarded as one of the most important and widely used treatment processes of industrial wastewaters due to its simplicity and effectiveness. This paper provides a critical review on recent studies of coagulation–flocculation treatment processes of various industrial wastewaters. The limitations and challenges for the coagulation–flocculation process such as the toxicity and health hazard posed by inorganic coagulants, production of large amount of toxic sludge, ineffectiveness in removing heavy metals and emerging contaminants, increase in effluent color, inefficient pollutant removal using natural coagulants, and complexity of scaling up procedure are presented. In addition, an overview on the influence of process parameters on treatment efficiency is included in this revie...

Recent Advancement of Coagulation–Flocculation and Its Application in Wastewater Treatment

Hexavalent chromium removal from aqueous medium by activated carbon prepared from peanut shell: Adsorption kinetics, equilibrium and thermodynamic studies

Constructed wetlands for treatment of industrial wastewaters: A review

Chemical and biological treatment technologies for leather tannery chemicals and wastewaters: a review.

Wastewater treatment in dairy industries — possibility of reuse

Treatment of tannery wastewater by chemical coagulation

An upflow anaerobic fixed biofilm reactor (UAFBR), which retains a high concentration of accumulated biomass in the form of biofilm supported by a carrier, has been developed to treat tannery wastewater. The effects of major process variables such as hydraulic retention time (HRT), organic loading rate (OLR), temperature on chemical oxygen demand (COD) removal, and methane yield performances of the reactor were evaluated. The technology ensures the retention of the active methanogenic biomass within the reactor, independent of the HRT, with minimum particle washout. This aids the conversion of COD and results in a reduction in effluent suspended solids (SS). COD removal (60-75%) and methane yield (0.36 m3 CH4/kg CODrem) remained stable across a range of organic loading rates and under conditions of temperature shock. The COD removal and methane yield is higher than the values reported previously. The biofilm colonisation on two types of microcarriers was compared. Porous polyurethane foam material was fou...

Z. Song

Papers

Treatment of tannery wastewater by chemical coagulation

Tannery wastewater treatment using an upflow anaerobic fixed biofilm reactor (UAFBR)