DEWATERING OF WASTEWATER SLUDGE USING BIOFLOCCULATION
Abstract
Sludge dewatering is a crucial stage in wastewater treatment that significantly affects treatment facilities' environmental and economic efficiency. This article explores the issue of wastewater sludge dewatering using bioflocculation, a biotechnology that involves the natural process of particle aggregation involving microorganisms or their metabolites. Biological wastewater treatment remains a leading approach globally and in Ukraine; however, existing sludge dewatering methods face limitations due to high costs and insufficient efficiency. Bioflocculation helps reduce sludge moisture content, increase dry matter concentration, and decrease waste volume, contributing to resource savings and reduced chemical load. The study analyzes the impact of microbial bioflocculants on sedimentation and dewatering processes, particularly exopolysaccharides produced by Bacillus, Pseudomonas, and Klebsiella bacteria. Parameters influencing efficiency, such as dosage, contact time, pH, and aeration, are considered. Combining bioflocculation with conventional methods, such as centrifugation and mechanical thickening, enhances treatment efficiency while reducing energy and reagent consumption. Special attention is given to the potential implementation of bioflocculation at Ukrainian treatment plants, where the local production of microbial bioflocculants could replace synthetic polymers. Key influencing factors — microbial community composition, physicochemical properties of sludge, and cultivation conditions — are analyzed for their impact on process stability. The advantages of bioflocculation are outlined, including environmental friendliness, reduced product toxicity, improved dewatering, and cost reduction. At the same time, challenges such as microbial adaptation, wastewater variability, and the need for further research to implement the technology are acknowledged. Therefore, bioflocculation is a promising approach to improving wastewater treatment and sludge dewatering, aligning with modern environmental standards and supporting sustainable waste management.
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