Unlocking bioremediation potential: harnessing an indigenous bacterial consortium from effluent treatment plants for industrial wastewater treatment

Abstract

Common Effluent Treatment Plant (CETP) wastewater poses significant environmental and health risks, necessitating advanced treatment technologies to meet discharge standards. This study focuses on the collection and characterisation of wastewater from CETP Vatva, Ahmedabad, to evaluate physicochemical parameters heavy metal concentrations, and identify indigenous bacterial species. Using Taguchi's systematic orthogonal array, an effective indigenous bacterial consortium (EIBC) was created for bioreactor-based CETP wastewater treatment. The 16S rDNA analysis revealed the presence of various bacterial strains, including the newly reclassified bacteria Stutzerimonas stutzeri. The analysis of the SI sample indicated substantial reductions in the concentrations of total dissolved solids (1090 mg/L), biological oxygen demand (28 mg/L), chemical oxygen demand (180 mg/L), and total phosphorus (1.4 mg/L) compared to their initial values of 7504 mg/L, 296 mg/L, 588 mg/L, and 3.04 mg/L, respectively, with a similar trend observed in samples SII and SIII. While turbidity was significantly reduced from initial concentrations ranging between 36-42 NTU to 4 NTU in SI, 5 NTU in SII, and 3 NTU in SIII samples, resulting in clear water, odour remained a persistent concern throughout the study. Heavy metal concentrations were within permissible discharge limits, with notable removal rates for Cu, Fe, and Cd. The study concludes that integrating systematic design modelling with bioreactor-based remediation effectively mitigates water pollution and safeguards human well-being.