Abstract:
The current study has been carried out to apprise the water footprint in terms of
water consumption and effluent generation and to assess the performance efficiency of
an effluent treatment plant (ETP) at Attock Refinery Limited. The samples were
analyzed for wastewater quality parameters from raw and effluent (treated) stream,
characterized their concentration load and compared with Punjab Environmental
Quality Standards (PEQS) and International Finance Corporation (IFC), World Bank
guidelines. Current treatment train mainly consists of API separators, DAF and
activated sludge process. Grab samples were collected from DAF-inlet and final
effluent outfall and tested for physico-chemical and heavy metals using instrumental
methods and atomic absorption spectrometer. The parameters analyzed for the
wastewater quality assessment were pH, Temperature, TSS, TDS, BOD5, COD, O&G,
Phenols, TN, TP, Free Cyanide, As, Hg, Fe, V, Pb, Ni, Cr and Cu. The results indicated
that the treatment plant was effective in reduction of some parameters like TDS, TSS,
As and Fe while concentration for Phenols, O&G, BOD5, and COD were above the
permissible limits of both EPA and IFC, World Bank. Hg, Cu and free cyanide were
detected in one effluent sample each whereas V, Pb, Ni, and Cr were undetected
throughout the sampling campaign. Efficacy or performance of treatment system was
determined based on pollutant reduction to acceptable discharge limits while Pearson’s
coefficient determined the correlation among various parameters. The study concluded
that some pollutant parameters are being discharged in the Soan water body very close
or in excess to the prescribed limits and an optimization of the treatment system is
required by installing advanced (tertiary) treatment units.
