Exploring Different Pretreatment Methodologies for Allowing Microalgae Growth in Undiluted Piggery Wastewater

The overapplication of manure on agricultural soils leads to nitrogen and phosphorus discharge into the aquatic environment, resulting in serious eutrophication problems decreased water quality. Piggery wastewater (PWW) can be treated by microalgae recycle nutrients, but toxic levels ammonia organic matter hinder their growth. Fresh is usually used dilute PWW, it a scarce resource. implementation pretreatment step before microalgae-based treatment could make PWW suitable for Electrocoagulation, stripping, photo-Fenton, constructed wetlands were evaluated as methods reduce ammonia, chemical oxygen demand (COD), color, total suspended solids. Moreover, pretreated PWWs tested grow microalga Tetradesmus obliquus. Photo-Fenton showed best results among other pretreatments, achieving removal efficiencies above 90%, except ammonia. This resulted T. obliquus being capable growing undiluted even at higher levels, similar biomass productivity synthetic medium (66.4 ± 17.8 mg·L−1·day−1 60.1 10.4 mg·L−1·day−1, respectively) almost doubling with pH control (116.5 mg·L−1·day−1). Thus, this seems most promising one incorporate systems must further explored.