Removal of Turbidity and Effectiveness as Disinfectant of Water Using Eco-friendly Methi Seed Powder

Abstract

Coagulation-Flocculation followed by sedimentation and filtration is the most commonly used water treatment process. Synthetic coagulant has both health and economic problems especially in developing countries. Natural and herbal coagulants have been used in developed countries since last centuries. This research was carried out to confirm the effectiveness of powder extracted from dried Trigonella foenum graecum seeds, a cheap, readily available local coagulant and readily biodegradable natural product. This work investigates on performance of methi seed powder (Trigonella foenum graecum) in removing turbidity at optimum dose. The quality of water was analysed and compared with alum treated water. 1.0M NaCl extract was found to be more efficient than that of aqueous extract in turbidity removal. The turbidity removal efficiency using 1.0 M NaCl extract was measured upto 95%. For continuous flow 0.9 m distance seems to be enough for turbidity removal using methi seed powder. The coagulant did not have considerable effect on final pH of the water. Methi can be used as coagulant but suitable for turbidity 20-150 NTU and flow rate about 3.5 liter/minute. The aqueous extract of methi seed powder did not show the disinfectant properties and therefore cannot be used at field. High turbidity determined in this study indicates that Trigonella foenum graecum, a natural coagulant, can be potentially viable substitute to alum in treatment of water.