Phytoremediation Of Dairy Waste Water Using Aquatic Macrophytes

Abstract

Dairy industries generate large volumes of nutrient-rich wastewater containing dissolved sugars, proteins, fats, and other organic matter. This effluent, characterized by high biochemical oxygen demand (BOD) and chemical oxygen demand (COD), cannot be discharged into the environment without treatment. Conventional treatment methods, although effective, are costly and require skilled operation. This study evaluates the phytoremediation potential of hydrophytes—Water Hyacinth (Eichhornia crassipes), Duckweed (Lemnoidae), Water Lettuce (Pistia stratiotes), Kariba Weed (Salvinia molesta), and Azolla—for dairy wastewater treatment. Wastewater samples were collected from a dairy plant and analyzed for pH, electrical conductivity, total solids, alkalinity, hardness, dissolved oxygen, BOD, and COD over a 28-day period under controlled laboratory conditions. Results indicated that Azolla achieved the highest reduction in most physicochemical parameters, particularly hardness, TDS, BOD, and COD, while Duckweed was most effective in turbidity reduction. The findings demonstrate that phytoremediation using floating aquatic plants is an eco-friendly, cost-effective, and sustainable alternative for dairy wastewater treatment.