Flocculation and Coagulation Process of Dye Wastewaters Cleaning Using Neutral Metal Salt and Multi-Layer Filtration

Abstract: Handloom weaving has been a foundation of traditional textile production across India, supporting the livelihoods of rural artisans. The sector is mostly decentralized. The dyeing operations associated with this industry generate substantial volumes of wastewater, contributing to environmental pollution and water scarceness. This study aims to develop a cost-effective and eco-friendly decentralized wastewater treatment system personalized to the needs of handloom clusters. The research focuses on the treatment of sulphur and reactive dye wastewater, emphasizing colour removal and chemical oxygen demand (COD) reduction using a combination of coagulation/flocculation (CF) followed by multilayer membrane filtration. The study systematically evaluates the performance of neutral metal salts, including Magnesium chloride (MgCl₂), Aluminum sulphate (Al₂(SO₄)₃), Ferric chloride (FeCl₂), and Calcium carbonate (CaCO₃), to determine the most effective coagulant for optimal dye removal and pH neutralization. The proposed treatment approach aims to enable the safe reuse of treated water in the dyeing process, reducing freshwater dependency and promoting sustainability in the handloom sector. Findings indicate that integrating efficient coagulation-flocculation mechanisms with gravity-based filtration systems can provide a scalable and decentralized wastewater treatment solution for rural handloom clusters. The study underscores the potential of low-cost, environmentally sustainable water management practices, offering a viable alternative to conventional wastewater disposal methods in Impoverished regions.

Keywords: wastewater treatment, handloom industry, dye effluent, coagulation-flocculation, metal salts, COD reduction, colour removal, sustainability.