Desalination of Produced Water Using Bentonite as Pre-Treatment and Membrane Separation as Main Treatment

Produced water is any water that is present in an oil and gas reservoir and is frequently referred to as "connate water" or "formation water". It will become produced water when these fluids are brought to the surface. Due to the hazardous content in the produced water, it needs to be treated prior being released to the environment. This study is carried out to determine the capability of bentonite to adsorb Total Dissolved Solids (TDS) of the produced water after it was brought from the offshore. This pre-treatment is to ease the separation of polymeric membrane for a better produced water treatment. Produced water was tested by using the membrane testing rig to determine the TDS rate of rejection and the membrane permeate flux per unit area. The process will be conducted in three different conditions; 1) without the addition of bentonite, 2) with the pre-treatment using bentonite and 3) with the pre-treatment using bentonite and the addition of bentonite in the membrane solution, in order to determine which approach give the best results. From the result of experiments, set 23 of polyethersulfone membrane (PES) was chosen as the best membrane based on its rejection rate and permeation flux of 17.15% and 0.0453 ml/cm(2).psi. Therefore the study suggested that pre-treatment using bentonite is promising approach to enhance the membrane performance in treating produced water. (C) 2015 The Authors. Published by Elsevier Ltd.