NITRATE IN WATER AND WASTEWATER-REVIEW AND RECENT TRENDS

摘要

Nitrate is the most common contaminant in both surface water and groundwater. It is the oxidized form of nitrogen formed naturally through decomposition of organic matter. Also, rainwater washes fertilizers seeping nitrates into groundwater. Municipal sewage discharge and effluents from sewage treatment facilities further add nitrate in water. Therefore, the amount of total nitrate is determined by both natural processes and human interventions. Excess nitrate can interfere with the oxygen carrying capacity of red blood cells causing methemoglobinemia in infants. Freshwater with higher nitrate concentrations promotes algal growth inducing stress conditions for the survival of fish and invertebrates. This algal bloom in freshwater is often referred to as eutrophication affecting freshwater species at large. Increasing advent of nutrient load and nitrate contamination in wastewater and surface water has been frequently reported. This manuscript thus deals with a summarized review and recent trends on nitrate contamination of water and their effective treatment solutions based on the nitrate removal techniques studied by us.