HYBRID MICROALGAL-ACTIVATED SLUDGE TREATMENT PROSPECTS: A REVIEW
An enormous amount of wastewater was produced due to domestic, municipal, agricultural, and industrial activities of varying strength and contamination. These usually contained a high level of pollutants that include inorganic and organic pollutants, pesticides, and heavy metals. Physio-chemical treatment approaches were employed to treat these recalcitrant contaminants and effectively handle extremely toxic substances within a short period. However, despite this, these treatments were associated with setbacks, including incomplete pollutant removals, lack of multiple pollutants removal capabilities, excessive sludge production, and cost of energy and chemical employed. Hybrid microbial treatment systems were efficient due to their potential to remove multiple contaminants like heavy metals, BOD, COD, assimilate nutrients, production of renewable energy alternatives, and easily recycled or regenerated. The future bottleneck in terms of best microbial proportions for higher growth rates and removal efficiencies is highlighted.
Keywords: algae, bacteria, proportion, heavy metals, adsorption, toxic
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