Coupling cold plasma and membrane photobioreactor for enhanced fouling control during livestock excreta treatment

To treat high-turbidity livestock excrements (LE), this study suggests a synergistic system coupling cold plasma (CP) and membrane photobioreactor (MPBR). During the continuous operation of the integrated system, physico-chemical oxidation of CP decompose turbidity and total suspended solids (TSS) up to 99.9%. The microalgal concentration of Scenedesmus obliquus in the following MPBR reach as high as 1,944 mg D.W./L, which indicates the residual organic and inorganic substances were actively consumed by phototrophic metabolism. Pearson correlation analysis confirms this synergistic relationship of turbidity and TSS with biological growth parameters such as biomass growth, soluble microbial products, and extracellular polymeric substances. Results evidence that the turbidity and TSS are directly connected to the microalgal growth in this integrated system thus the role of CP is crucial to achieving the LE treatment goal. Overall, this study provides a guideline to support the enhanced treatment strategy to control LE with the production of bioresources for sustainable carbon and nutrient cycles.