Choosing Produced Water Treatment Technologies Based on Environmental Impact Reduction

Abstract

Abstract Reduced environmental impact should be the goal when choosing produced water treatment technologies. On the Norwegian sector the method used for quantifying this impact is the Environmental Impact Factor, EIF. This method is computerized in a tool that calculates the environmental impact from each of a number of chemical component groups that are present in produced water. Reinjection of produced water is obviously an option that should be considered if the reservoir needs pressure support. This paper, however, describes four new treatment technologies aimed at produced water being released to sea. The technologies are suitable for different produced water compositions. The four technologies described are the PECT-F (Performance enhancing coalescence technology) for enhanced removal of dispersed oil, the MPPE (Macro Porous Polymer Extraction) technology for removal of volatile aromatics, the CTour technology for the removal of heavy aromatics and alkylated phenols, and the Framopure C100 injection system for H2S scavenger. The potential of these technologies has been illustrated by choosing typical produced water compositions where one of these technologies has a significant potential to reduce the environmental impact. Given an estimated efficiency of these technologies, the EIF is calculated before and after applying the technology to show the reduced environmental impact obtained. The main conclusion is that knowledge is needed about which compounds contribute to the environmental impact of produced water before deciding which technology to use. Results are also presented that correlate the content of dispersed oil and PAH (poly aromatic hydrocarbons).