Analysis Of Kasur Tannery Pre Treated Wastewater For Rendering It Fit For Irrigation

Abstract

Kasur district is famous for leather tanning and its leather products are used worldwide, and thus it contributes significantly to GDP of Pakistan. However, the wastewater generated from the cluster of tanneries of Kasur is highly polluted with obnoxious odor and is also loaded with hazardous pollutants. Thus, Kasur Tannery Waste Management Agency (KTWMA) has installed Common Effluent Pretreatment Plant (CEPTP) that discharges 9000m3pretreated wastewater per day. The present study is carried out to analyze pretreated tannery wastewater to judge its suitability for irrigation of agricultural soil and propose methods and their subsequent economic evaluation to fit this water for irrigation purposes.

Physicochemical analysis of pre treated tannery wastewater was carried out. The concentrations of various parameters such as pH, EC, TDS, SAR, RSC, SO42-, Cl-, Cr, Cd, Zn, Fe and Cu were computed and compared with the standards of wastewater for irrigation purposes proposed by WWF (2007). The results reveal that the concentrations of heavy metals are in permissible limits except of Cr (0.283mg/L). The concentrations of remaining parameters such as EC (18.6 dS.m-1), TDS (13020 mg/L), SAR (91.7), RSC (35.86), SO42- (8061.3mg/L) and Cl- (8930.7mg/L) are much above the permissible limits

The study concludes that the pretreated wastewater is not suitable for irrigation purposes even after mixing it with municipal wastewater on way to Pandoki Drain. The best technology to treat wastewater that may be opted especially from salinity point of view is Reverse Osmosis (RO). However its cost benefit analysis shows that it’s not feasible for a country like Pakistan where economic and electricity crisis are at its peak.