The Use of Design of Experiments for Development of Flocculating Agents for Treatment of Crude Oil Emulsions

Abstract

Abstract Emulsions are formed during crude oil production due to the presence of natural surfactants and brine in the petroleum fluids. In addition, turbulence wich the produced fluids are subjected to, either initiated by differential pressure in the drawdown region near the wellbore or in presence of a pumping system, also exacerbates the emulsion problems. Water-in-oil emulsions are the most common type of colloidal dispersion experienced in oilfields. The stabilization mechanism for those dispersions are not fully understood and, overcoming all the stabilization mechanisms present, make the selection of the desired demulsifier for breaking the water-in-oil emulsion very challenging. The use of the right treater, also known as dryer or flocculating agent, is paramount in order to achieve the requirements such as less than 1% BS&W. On the other hand, the standard procedure in the Oil and Gas industry widely used today for screening emulsion breaker intermediates and final demulsifier formulations is still a trial-and-error methodology, which does not correlate the physical-chemical properties to the application performance. For this reason, a Design of Experiments study was used for the development and selection of amine-based flocculating agents, based on relevant parameter investigation, such as Surface Tension (ST) and Relative Solubility Number (RSN). The objective was to use statistical treatment to optimize the flocculants agent molecules aiming to obtain relevant improved results concerning petroleum dehydration during emulsion breaker studies.