Snack-food industry effluent pre-treatment for annatto dye and yeast removal: Process improvement for effectiveness and sustainability

摘要

Wastewater from snack foods manufacturing processes may contain significant amounts of pollutants that may affect receiving municipal treatment facilities. Their removal with onsite pre-treatment is therefore necessary, to avoid costly discharge fees. This paper presents a study of two common pollutants in snack-food industry wastewater, namely annatto dye and yeast, in view of planned changes at a production facility. Analyses were conducted to determine the new raw wastewater composition discharged into the municipal wastewater system after local pre-treatment. The most relevant issue affecting effluent quality after the introduction of new ingredients, would be the generation of an effluent no longer compliant with discharge requirements. Pre-treatment upgrade options were studied, showing that annatto removal from process wastewater can be successfully achieved with minor modification of the current process. Yeast removal, instead, would require major interventions on existing processes, hence an alternative approach strategy is proposed. (C) 2020 Elsevier Ltd. All rights reserved.