Anaerobically Digested Distillery Wastewater Treatment Using Coagulation–Flocculation Followed by Microalgal Treatment: Optimization of Coagulant Dosage, Dilution Ratio, and Photoperiod

Abstract

The treatment of anaerobically digested distillery wastewater (ADWW) was investigated via coagulation–flocculation (C–F), followed by a microalgal system. As a first step, C–F was carried out using FeCl3 and polyaluminum chloride (PAC). Around 99.3%, 73.6%, and 58.3% of turbidity, color, and chemical oxygen demand (COD) removals, respectively, were observed under optimized C–F conditions (FeCl3 approximately 3 g/L, PAC approximately 6 mg/L, pH approximately 5, and dilution ratio approximately 4D). Subsequently, C–F-treated ADWW (CADWW) was subjected to microalgal treatment under various dilutions (1D–30D, with and without