Investigation of pumpkin seed as A Potential Coagulant for Drinking water Treatment

This research investigated the potential of pumpkin seed as a natural coagulant for water treatment. This is aimed at identifying pumpkin seed as possible supplement for alum and other synthetic polyelectrolytes in treating water. Natural coagulants are mostly effective and simple to apply for the removal of colloidal and suspended solid contaminants from water. Moreover, the use of chemical coagulants have been criticized, because of certain constraints, such as concern for human health, costs of chemicals and the problem of sludge management (particularly in developing countries). Laboratory scale studies using jar test experiments were performed to determine the effect of dosage, pH and mixing speed. For better turbidity removal efficiency, the aforementioned three factors were optimizing response surface method. The pumpkin seed powder was characterized for physicochemical properties according to standard procedures. Functional group identification study also confirmed the presence of various functional groups which are responsible for the coagulation process such as –OH, C-O, C-H, N–H and -COOH. The raw water characteristic of some parameters measured before jar test were: Temperature 21.2 0C, pH 6.79, Turbidity 296 NTU, Hardness 113.16 mg/l, TDS 69mg/l, TSS 87.94 mg/l, TS 156.94 mg/l, EC 127.33 μS/cm, BOD 288.33mg/l, and COD, 302mg/l. Quadratic design model was developed to correlate the parameter variables to the turbidity removal percentage. Optimum coagulation was obtained at coagulant dose of 1.01367 g/l, pH 9, and mixing speed of 135.758 rpm. Under this optimal condition, the turbidity removal efficiency was 87.695 %. Therefore, response surface method might be used to optimize the coagulation process using pumpkin seed for drinking water treatment. Hence, it can be concluded that pumpkin seed powder can be used as coagulant to remove turbidity in surface water for drinking water treatment.