Application of Dragon Fruit Peel’s Mucilage in Coagulation – Flocculation Process to Remove Turbidity from Water

Abstract

The study determined flocculation activity of mucilage extracted from dragon fruit peel (Hylocereus undatus) and its ability in reducing synthetic coagulant polyaluminium chloride (PAC) used in coagulation – flocculation process to remove turbidity of different types of water. Investigated waters were turbid waters made from kaolin suspension (KS), suspension of river water with hill soil (FW), and To Lich river water (TL). Turbidity removal was assessed in a sequent coagulation and flocculation model using PAC and mucilage extracted from dragon fruit peel in Jar-tests. Optimal coagulation conditions of PAC with PAC dosage of 20-50 mg/L and pH range of 6-8 regardless of water types and resulted in maximum turbidity removal of about 98%. In order to obtain a comparable turbidity removal, 50%-68% of the required PAC was reduced if mucilage was used. The presence of mucilage enhanced turbidity removal of PAC by 13-22% total efficiency. Mucilage extracted from dragon fruit peel has shown its flocculation ability and its potential as a green material in water treatment.