ECONOMICAL APPROACHES FOR THE TREATMENT AND REUTILIZATION OF LAUNDRY WASTEWATER - A REVIEW
This paper provides an elementary characterization of laundry wastewater (LWW) and treatment techniques with their installation and operation cost analysis for potential chemical removal such as surfactants i.e., linear alkylbenzene sulfonates (LAS), chemical oxygen demand (COD), nitrate, sulphates and phosphate found up to 1024, 4474, 25.7, 102.6 and 279 in mg/L, respectively. LWW also contains solids, turbidity, low levels of alkalinity, volatile acids, deodorizing agents, fabric, food, body fluids, non-biodegradables, and a few metals like Zn, Ni, Fe, Cu, Pb and xenobiotic organic compounds. The treatment techniques for LWW as physical treatments includes sedimentation and filtration for particulate matter and adsorption using granular activated carbon (GAC) or bio-char are used to reduce the COD, BOD, anionic surfactants, total solid and turbidity by 50-95%. Bio-char is more preferred than activated carbon because it is 60% more economical and facilitates E. coli removal. Chemical treatments such as coagulation integrated with GAC results in 80-95% removal of COD, BOD, total phosphorous and anionic surfactant. Biological treatment and phyto-remediation take more time but they are the most eco-friendly strategies to employ. Each technique can serve according to each project’s budget, material availability and according to the desired utilization or application. In this review, the best cost effective trends are highlighted along with recommendations for further developments. This paper further highlighted the current knowledge gaps and future research directions for the application of these technologies for wastewater treatment and reuse.
SURAJ KUMAR BHAGAT, TIYASHA1 AND DAWIT N BEKELE