Plant-Based Flocculants: Alternative Materials to Synthetic Polymers for Sludge Dewatering

The use of conventional organic or inorganic synthetic chemicals in sludge dewatering process is currently leading to new concerns. Worrying issues are related to the pollution of the environment and the risks for human heath caused by the generation of large quantity of sludge containing residual metal ions and toxic residual organic monomers. Plants such as okra, cactus, moringa and aloe showed their ability in enhancing sludge dewaterability. Interestingly, the utilization of plant-based materials produce nontoxic and biodegradable sludge, and represent a sustainable strategy to substitute chemicals in sludge processing.