Cost Effective Wastewater Treatment Technique for Bara Nulla Peshawar

Abstract

Various samples from Bara Nulla in Peshawar were collected and analyzed, using standard methods for various important wastewater parameters. The effluent discharge from the nulla is highly polluted in terms of its physical and chemical properties. Most of it parameters do not meet the requirements of Pak-EPA NEQS limitations set for industrial and domestic effluent discharge. The average wastewater characteristics of nulla in terms of COD, BOD, TDS, TSS, turbidity and pH are 9600, 7450, 1650, 2280 mg/L, 1489 NTU and 6.5 respectively. Treatability of nulla wastewater alone in plain sedimentation seems to be non-feasible, as it does not give the required efficiency in terms of COD/BOD/TSS, etc., removal. The maximum COD, BOD, TDS, TSS and turbidity removal at 80 min of detention time is 13, 21, 10, 30 and 39%, respectively. Out of the three coagulants, namely alum, lime and magnesium sulfate, tested using the Jar Test apparatus, alum is considered to be most suitable in terms of treatability performance that gives 80% of COD removal. Lime and magnesium sulfate give about 56 and 71% removal, respectively. The total cost for using alum as a coagulant is about USD1.4/day for an average flow of 100 L/min.