Study of the Potential of New Biological Technologies to Remove Emerging Contaminants from Wastewater

Due to population growth and increase in the usage of drugs and cosmetics as well as the inability of conventional processes of wastewater treatment to remove emerging contaminants such as PCPs, EDCs, surfactants, pesticides, industrial additives, and pharmaceutical organic pollutants, the effluents discharge in Iran's wastewater refineries may contain significant concentrations of emerging contaminants. The mechanism of biological removal of emerging contaminants from wastewater predominantly includes biodegradation by microorganisms such as bacteria, algae, and fungi into small molecules or water and carbon dioxide. Biological treatment technologies include a variety of conventional and unconventional methods such as activated sludge, MBR, aerobic, anaerobic, microalgae and fungi bioreactors, rotating biological reactor, trickling filter, nitrification and denitrification, biosorption, and constructed wetland. Therefore, wastewater characteristics play a key role in the selection of biological treatments. Based on previous research, the maximum removal efficiency of EDCs, beta blockers, and PCPs was revealed with MBR, surfactants, lipid regulators and anti-inflammatory with activated sludge, antibiotics and pesticides with biological activated carbon, analgesics with the aerobic process and other pharmaceuticals with microalgae. Due to the use of the activated sludge system for biological refinement in most wastewater refinement plants of Iran and the inability of this system to remove emerging contaminants, except surfactant, lipid regulators, and antiinflammatory, a national comprehensive research is needed for the removal of aforementioned contaminants by biological processes in future studies.