Efficiency of Moringa Pergerina to sludge conditioning in ferric chloride water treatment plant.

Abstract

Water sludge management is one of the main problems facing water and wastewater companies. Disposal of conditioned sludge by chemical polymers is restricted due to the health and environmental effects. Recently, the use of natural polymers has been investigated to reduce the side effects of chemical polymers. In this study, the effectiveness of Moringa Pergerina seed as a natural polymer in the conditioning of water treatment sludge has been studied. In this study, sludge samples from the Tehranpars Water Treatment Plant were taken daily from the sedimentation tank. Sampled sludge conditioning was performed using jar test by Moringa pergerina powder dissolved in salt water (1N NaCl). Optimization of three important factors in the jar test, including mixing speed, mixing time and optimum dosage using the Box-Behnken Design, Response Surface Design Method (RSM), was performed in Design Expert software. Results: The minimum capillary suction time (CST) and specific resistance filtration (SRF) was obtained at 30.294 and 6.19×1012 m / kg respectively under optimal conditions. The results were obtained in terms of speed and time of mixing 50 rpm and 3 min, 250 rpm and 100 s with an optimal dosage of 5040 mg/L of Moringa Peegerina dissolved in salt water and a desirability index of 1.000. The best effectiveness of Moringa Pergerina for sludge conditioning was obtained in acidic media. Under optimal operating conditions, SRF and CST relative to the initial conditions of the sludge was reduced by 75% and 42%, respectively.