Hybrid electrocoagulation constructed wetland system for sustainable water quality enhancement

Abstract

Water pollution has become a serious environmental problem because of industrial discharge, agricultural runoff, and urban wastewater; thus, the development of efficient and sustainable treatment technologies is needed. Artificial purification methods can remove contaminants quickly and efficiently, but often require large amounts of energy and chemicals. Natural purification systems are environmentally friendly but are generally less efficient, and their performance is inconsistent. The present study aims to investigate a hybrid water treatment system combining electrocoagulation-filtration (EC-F) and Constructed Wetland Microbial Treatment (CWMT) to take advantage of both and to improve the overall treatment performance. The study was carried out using a mixed-method experimental design for water quality assessment, assessment of artificial and natural purification mechanisms, development of a hybrid treatment prototype, and validation of performance under stagnant and flowing water conditions. The parameters studied were turbidity, total dissolved solids (TDS), oxygen demand (BOD), chemical oxygen demand (COD), heavy metals, and coliform bacteria. The experiments showed that EC–F was more efficient at removing physicochemical contaminants, whereas CWMT was more efficient at biological stabilization and reduction of microorganisms. The optimized EC–CW hybrid system was found better than individual treatments, with removal efficiencies > 92% for turbidity, 88% for TDS, 94% for BOD and COD, 96% for heavy metals, and 97% for coliform reduction in both hydraulic conditions. Statistical analysis showed that the treatment systems were significantly different from each other (p<0.001), with large effect sizes, which showed a high impact and reliability of the treatment. The hybrid system achieved a Water Quality Index (WQI) of 94.9 ± 1.2, indicating excellent quality of treated water. These findings validate that the integration of electrocoagulation and constructed wetland microbial treatment is a resilient, energy-efficient, and environmentally sustainable approach for advanced water purification. The proposed hybrid framework has great potential for application in decentralized water management, restoration of ecosystems, and long-term sustainability of water resources in a wide range of aquatic environments.