Efficiency of <i>Moringa oleifera</i> and Polyaluminium Chloride for Sludge Thickening

Abstract

The viability of using Moringa oleifera seed extract as a plant based coagulant in comparison to Polyaluminium Chloride a commonly used chemical coagulant for the thickening of activated sludge was investigated. Moringa oleifera also known as the drumstick tree or horseradish is widely found throughout Mauritius. This tree is considered as a miracle tree by many researchers due to its numerous benefits ranging from purification of water to the manufacture of oil and biodiesels. To investigate the coagulant properties of the Moringa oleifera and Polyaluminium Chloride, the zone settling test and the jar test were conducted. The zone settling tests and the jar tests showed a difference ranging from 2.1%- 4.8% for the first 30 minutes for Moringa oleifera and Polyaluminium Chloride which showed similar coagulant relationship. Thus Moringa oleifera was found to be as efficient as Polyaluminium chloride and can thus be easily used as a natural coagulant.

Keywords: Moringa oleifera, Polyaluminium Chloride, Activated Sludge, Natural Coagulant, Flocculation