Electrocoagulation
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Water Recycling and Desalination for the Oil and Gas Industry Title: Electrocoagulation: An Innovative Approach for Recycling Produced Water and as a Pre-Treatment to Reverse Osmosis for Emulsified Oils, Heavy Metals and Other Constituents in the Oil and Gas Industry Author(s): B. Denney Eames, Jim Mothersbaugh, Karl W. Yost, Bryan Nielson Country of attribution: USA Presenter: B. Denney Eames Organization: Water Tectonics, Inc. Abstract Although the basic concepts of electrocoagulation (EC) have been known for nearly 100 years, it was not until the past few years that the technology became commercially viable for large scale, high flow rates applications. Through innovations in electric power management, electrode configuration and geometry, in-line real-time sensory monitoring and integrated control, and the ability to efficiently treat large water flows, EC now provides an innovative and cost-effective approach to the treatment of water impacted with non-settleable suspended solids, emulsified oils, heavy metals, and other constituents. As a work horse technology for the removal of total suspended solids and turbidity without the use of polymers or coagulant chemicals, EC is also an ideal pre-treatment option to reverse osmosis (RO) membranes for heavy metals and other analytes that are often factors that cause scaling, fouling, and compromise reject brine/permeate ratio performance. Conventional EC processing of water includes up front oil/water and flotsam separation, grit/settleable solids removal; EC processing, clarification settling, and filtration. For more than four years, EC has been effective used to treat water streams from various oil and gas produced water sites in Canada, United States, and Colombia. Parameters effectively removed from the water streams by EC typically attributed, in part, to membrane fouling and adverse performance included: fats, oils and grease (FOGs), total petroleum hydrocarbons (TPH), iron, aluminum, manganese, silica, Total Suspended Solids (TSS), turbidity and others. Ranges of parameter concentration removal as a result of EC processing were: up to 100% (MDL based) for iron and aluminum; 55-98% for manganese; 71-98% silica; up to 99% of FOGs and TPH, up to 98% of TSS; and 97-99.9% of Turbidity. Real world case studies will be presented where EC was used as a pretreatment to RO technology. Modeling result comparisons of untreated vs. treated water data will show that premature membrane fouling/scaling, and/or cost prohibitive performance for untreated water, whereas EC pre-treated water without polymer or coagulant chemicals significantly enhanced RO output, minimized the use of membrane antiscalant chemicals, or allowed for RO membrane processing where otherwise RO was not technically feasible. Banff, Alberta Canada / 12-14 May 2013 REF: IDABANFF2013-015 .