Preliminary studies on removal of nitrate and hardness from ground water using polystyrene beads

摘要

Ground water has emerged as the primary water deficiency reduction tool in most developing countries. Recently, the quality of ground water has deteriorated due to over-exploitation and contamination resulting from anthropogenic activities. A broad range of physical, inorganic and organic, bacteriological, and radioactive parameters are found in ground waters. The presence of nitrate and hardness-causing ions at elevated levels is of greatest concern currently, as they can have a serious impact on human health and water distribution systems. The conventional methods which are applied to reduce the concentration of these inorganic constituents are found to be inconsistent when the concentration is significantly high. The present study is an attempt to remove nitrate and hardness-causing ions using polystyrene (PS) beads as packed media. The ground water sample had a total hardness between 1,030-1,250 mg/L, which is greater than the permissible limit, and the nitrate concentration was less than 45 mg/L. PS beads packed media was found to respond significantly in reducing nitrate by 88% and total hardness by 38% at an optimum flow rate and particle size of 3 L/min and 4 mm diameter respectively. PS beads can be a promising media in reducing nitrate and total hardness.