Legislation worldwide and current technologies used in the treatment of offshore oil and gas/condensate produced water are mainly aimed at the removal of dispersed hydrocarbons (dispersed oil). From the beginning of this century, new insights in the North Sea area revealed that specific contaminants in produced water are toxic and their impact on the environment was assessed. This insight was later supported by work in the Philippines. A comparison of water with the same total organic carbon (TOC) levels showed in one case that the unknown toxic content was higher with an unexpected disastrous effect on the biocultures. Overall parameters like biological, chemical and total oxygen demand (BOD, COD and TOC) are of no value in identifying and managing the toxic content of waste and produced water streams. New extraction based technologies such as the Macro Porous Polymer Extraction (MPPE) technology appear to remove dispersed and dissolved toxic constituents and reduce the environmental impact. Industrial applications show a >99% toxic content reduction in produced water streams. A recent application (at Woodside Petroleum’s Pluto LNG project) is described where the ultimate reuse of produced water was as demineralised water in an LNG plant. Emerging potential is presented for floating LNG plants currently investigated in conceptual studies by the oil and gas industry. Finally, fundamental technological mechanisms are presented that are required to meet zero harmful discharge legislation.
MPPE, produced water reuse, wastewater reuse, ground water reuse, dissolved and dispersed hydrocarbons, zero armful discharge, ZHD, Environmental Impact Factor, EIF.
Removal of dissolved and dispersed hydrocarbons from oil and gas produced water with MPPE technology to reduce toxicity and allow water reuse