A Review on Advancements and Challenges of Catalytic and Non-Catalytic Waste Water Treatment Processes

Abstract

Abstract

Clean drinking water is a basic amenity to be ensured for all. As water resources are becoming increasingly scarce due to the rising imbalance between freshwater availability and consumption and many of the water resources are polluted by anthropogenic sources such as industrial, agricultural waste and household, therefore, treatment of wastewater remains a critical need before leaving it to natural water streams. Traditional wastewater treatment processes include filtration, adsorption, activated sludge treatment, coagulation, flocculation, etc. These are not sufficient enough to cope up with urban water treatment requirements. More advanced filtration techniques such as reverse osmosis, membrane bioreactor, etc are in use but these processes only remove contaminants and pollutants do not eliminate them. In the present situation, advanced oxidation process using green photo-catalysts with much higher photocatalytic efficiency is attracting attention. Other catalytic processes using catalysts are also drawing attention for the purpose. The ultimate goal of the wastewater treatment is to provide the protection in terms of human health and environmental aspect. This review emphasizes on the recent advancements and challenges of some sustainable integrated solution to the problem in a cost effective manner with optimal efficiency. The use of wastewater treatment methods such as advanced oxidation process using green phot-catalysts, bio reactor engineered wetland technology, adsorption, biosorption, nano-technology, membrane bioreactors, sludge optimization and power generation using salinity gradient have been discussed.

Keywords: Photocatalysis, Adsorption, Nanomaterials, Wastewater, COD, Sludge, Cow Dung