Organic pollutants abatement and biodecontamination of brewery effluents by a non-thermal quenched plasma at atmospheric pressure

A preliminary study was carried out to investigate possible decontamination of the waste waters from a Cameroonian brewery by using a non-thermal atmospheric plasma. Samples of waste waters collected during periods of intense activity of production were first analysed for organoleptic, physical–chemical and organic parameters, and then exposed to a humid air electric discharge at ambient temperature and pressure. The resultant pollution abatement and germicidal effects are both ascribed to strong oxidising effects of OH and NO radicals formed in the plasma. The BOD removal efficiency of the process with brewery industrial wastewaters under BOD concentration of 385 and 1018 mg l−1 were 74% and 98% respectively. The alkaline wastewaters are rapidly neutralised due to the pH lowering effects of the plasma treatment.