The Treatment Effect of Chemical Coagulation Process in South African Brewery Wastewater: Comparison of Polyamine and Aluminum-Chlorohydrate coagulants

Abstract

An evaluation of a laboratory scale chemical coagulation using aluminium chlorohydrate (1%) and polyamine (1%) coagulants on its effectiveness in the removal of bulk inert pollutant contents such as particulate chemical oxygen demand (COD) and turbidity to obtain clean effluent discharge and most cost-effectively treated effluent using a jar test was conducted in this current study. This study aimed to find the viable inert removal coagulant between the two above-mentioned coagulants in order to achieve zero liquid effluent discharge (ZLED). The preliminary results showed that adding variable dosages of polyamine and 50% aluminium chlorohydrate combined coagulants dosages presented an improved particulate chemical oxygen demand, color, and turbidity removal efficiencies. The ascertained turbidity removal efficiency using the combined coagulation dosage of polyamine–aluminium chlorohydrate (PAC) treatment was 90.50% and 59.36% particulate chemcial oxygen demand removal, as comparable to polyamine alone with particulate chemical oxygen demand removal of 50% and turbidity of 75%. Likewise, an appreciable removal efficacy was observed as the aluminium chlorohydrate treatment alone was for particulate chemical oxygen demand and turbidity was 37% and 54%, respectively. In essence, this study emphasized the knowledge gap of the significant effect of the polymeric polyamine flocculant strength in adopting the combined coagulation dosage method to improve its coagulation efficiency and the high agglomeration on suspended solids, thereby, removing more of the unwanted inert contents from brewery wastewater. To determine zero liquid effluent discharge, this study clearly recommended an integrated treatment approach, microbial fuel cell integrated with a lab scale chemical coagulation technique for efficient non-biodegradable pollutant removal.