A New Caustic Process for Softening Produced Water for Steam Generation

Abstract

Oilfield produced water containing a high concentration of total dissolved solids (TDS) and hardness can successfully be softened for use as oilfield steam-generator feedwater. At the Belridge field in Kern County, CA, the combination of caustic softening and weak-acid cation exchange has been used to soften produced water containing 11,000 TDS and 550-ppm hardness to < I-ppm hardness. The resultant sludge containing calcium carbonate and magnesium hydroxide is concentrated by centrifuging and is disposed of in a landfill. Compared to the use of conventional strong-acid ion exchange followed by weak acid or weak acid followed by weakacid ion exchange systems, the process offers the benefits of lower capital and chemical costs, partial silica removal, and elimination of liquid waste discharge. This paper gives design parameters and operating conditions and discusses future applications in thermal recovery projects.

Review of technologies for oil and gas produced water treatment

“…The chemical structure of strongacid-cation-exchange resin is sulfonated copolymer of styrene and divinylbenzene. When the TDS of produced water is higher than 50,000 ppm, sodium competes with calcium and magnesium for sites on the resin [44].…”

Recent Perspectives on the Management of Formation Water Generated from Hydrocarbon Reservoirs

“…Several conventional and hybrid treatment methods/technologies have been explored for the treatment of FW including adsorption, biological method, capacitive deionization, chemical oxidation, electrodialysis, ion exchange process, membrane filtration, and membrane distillation . These techniques are classified as physical, biological, and chemical.…”

“…Electrodialysis (ED) 29,30,65,66,69,70 Electrical force is applied in the feed side of the membrane instead of applied pressure.…”

Fabrication of highly hydrophilic filter using natural and hydrothermally treated mica nanoparticles for efficient waste oil-water separation

“…(Fried et al, 1979;Mazumder and Mukherjee, 2011) It is known that the prompt water pollution occurs when oil passes in to the water sources, rivers and sea water and the water pollution by oil is considered to be a greater threat to the humans, marine life, animals and to the entire ecosystem. (Fosberg, 1974;Nomack, 2010)In past few decades, the following water treatment techniques have been used; (a) physical treatment methods such as adsorption of dissolved organics on activated carbon, (Gur-Reznik et al, 2008) organoclays, (Doyle and Brown, 2000) copolymers and resins, (Jan and Reed, 1989) sand/stone filters, organics evaporating methods, (Fakhru'l-Razi et al, 2009) electrodialysis methods, (Fakhru'l-Razi et al, 2009) and filtering through oil/water separating membranes, (Kota et al, 2012); (b) chemical/electrochemical treatment methods such as coagulation and flocculation methods, (Bratby, 1980) advanced chemical oxidation methods, (Bautista et al, 2008) electrochemical methods (Ma and Wang, 2006) and photocatalytic treatment methods (Chong et al, 2010;Teng et al, 2015) and (c) biological treatment methods (Fakhru'l-Razi et al, 2009;Sugano et al, 2008;Teng et al, 2015). The major disadvantages of most of these conventional techniques are that these methods are not economical as well as they cannot separate oil/water emulsions efficiently.…”