Oil Removal from Oilfield Wastewater by Adsorption Using Activated Semicoke

摘要

Semicoke, the cheap by-product of coal gasification, was chosen as the raw material to prepare sorbents of oil removal from oilfield wastewater and the adsorption efficiency of different activated semicoke has been focused on. Different modification methods to raw semicoke were performed as followed: calcination in N2 atmosphere, steam activation, high-pressure hydrothermal chemical activation, HNO3 and KOH activation. The effects of activation conditions of sorbents and various operating parameters of adsorption process on the oil removal rate were investigated. The experimental results showed that the low-cost semicoke is feasible to be used as the sorbent in the treatment of oilfield wastewater, under the optimal conditions of mass ratio of KOH/semicoke 6:1, impregnating temperature 80 ℃, calcining temperature 550 ℃, bed height 100mm, wastewater flow rate 180ml/L, the optimum oil removal rate obtained could be up to 75.6 %.