Investigation of the Aging Effect of Bio-Coagulant for Oily Wastewater Treatment

Abstract

The separation of oily wastewater is one of the main processes in the water treatment field. A biological approach that can replace the use of chemical coagulants hazardous to human health is an efficient solution in treating oily wastewater. However, bio- coagulants have a time limit that can affect their effectiveness in treating oily wastewater. Thus, this paper presents research for the aging effect of bio-coagulant for treating oily wastewater. In this study, G-Treat was used as the bio-coagulant, which was produced from chitosan powder, acetic acid, and deionized water. The experimental procedure started by filling 500 mL of oily wastewater into a beaker. Next, 10 wt. % of G- Treat was added into the beaker for the jar test, which was mixed for 30 min at 150 rpm, followed by 2 h settling time. Then, the mixture was separated using filter paper. The analysis of oily wastewater characteristics was conducted using five types of analyses, which are pH, chemical oxygen demand (COD), biological oxygen demand (BOD), total sus- pended solids (TSS), and oil and grease (O&G) under the parameters of days (0–7 days), weeks (0–6 weeks), and months (0–3 months). From the result, the best performance of G-Treat was achieved at the optimum parameters during week 2, with 33.16%, 65.75%, 35.73%, 28.58%, and 0% removal of pH, COD, BOD, TSS, and O&G, respectively. In conclusion, the studied bio-coagulant demonstrated higher removal of pH, COD, BOD, TSS, and O&G at optimum parameters, and eventually, the level of effectiveness will drop.