Abstract: A method comprises the steps of receiving a wastewater containing solid particles in suspension, agitating the wastewater for a specified agitation period under specified agitation conditions sufficient to enable auto-flocculation of at least a portion of the solid particles into flocs to provide an agitated wastewater, allowing the agitated wastewater to settle for a specified sedimentation period to allow at least a portion of the flocs to settle, and separating at least a portion of the settled flocs from the agitated wastewater to provide a clarified wastewater effluent.

Abstract: A method comprises flowing a mixture comprising a water-based reaction medium and at least one microalgae into a reaction vessel, wherein the reaction medium comprises a nutrient material that is consumable by a live microalgae, bacterium, or protozoa present in the reaction medium, incubating the mixture under at least intermittent illumination with a specified luminous flux such that the microalgae forms a supporting matrix that incorporates the live microalgae, bacterium, or protozoa into biologically-active bioaggregate granules, selecting out a first specified portion of the biologically-active bioaggregate granules that are smaller than a first specified size or below a first specified weight or selecting out a second specified portion of the biologically-active bioaggregate granules that are larger than a second specified size or over a second specified weight and removing the first and/or the second specified portions of the biologically-active bioaggregate granules in an effluent stream.