Oil recovery, enhanced, sodium

PEG-20 hydrogenated castor oil PEG-3 lauramide PEG-5 lauramide Polyglyceryl polyricinoleate Quatemium-26 Steareth-9 stearate Steareth-10 stearate Steareth-12 stearate emulsifier, enhanced oil recovery Sodium didodecylbenzene sulfonate emulsifier, EP Sulfated rapeseed oil emulsifier, epoxies Polyamide... 

Because of its functionaUty and environmental acceptabiUty, citric acid and its salts (primarily sodium and potassium) are used in many industrial appbcations for cbelation, buffering, pH adjustment, and derivatization. These uses include laundry detergents, shampoos, cosmetics, enhanced oil recovery, and chemical cleaning. 

Associative copolymers of acrylamide with N-alkylacrylamides, terpoly-mers of acrylamide, N-decylacrylamide, and sodium-2-acrylamido-2-methyl-propane sulfonate (NaAMPS), sodium acrylate (NaA), or sodium-3-acrylamido-3-methylbutanoate (NaAMB) have been shown to possess the required rheologic behavior to be suitable for enhanced oil-recovery processes [1184]. 

Texas Permian Basin, enhanced oil recovery in, 18 615—617 sulfur deposits in, 23 570 Textile applications, sodium dithionite in, 23 676... 

The polymerization of acrylamide (AM) and the copolymerization of acrylamide-sodium acrylate in inverse microemulsions have been studied extensively by Candau [10,11,13-15], Barton [16, 17], and Capek [18-20]. One of the major uses for these inverse microlatexes is in enhanced oil recovery processes [21]. Water-soluble polymers for high molecular weights are also used as flocculants in water treatments, as thickeners in paints, and retention aids in papermaking. 

Emulsion Injection for Recovery of Heavy Oil. Oil-in-water emulsions may be useful as sweep improvement agents in heavy-oil reservoirs. To improve the mobility ratio occurring with high-viscosity oils, McAuliffe (69) and Schmidt et al. (70) proposed the use of stable oil-inwater emulsions. These authors conducted laboratory experiments with emulsions prepared by reaction of sodium hydroxide with a synthetic acidic oil. The theoretical background for emulsion blocking has been discussed in Chapter 6, and it forms the basis for one of several mechanisms of caustic flooding (7i). These emulsions may form spontaneously during oil recovery processes (72), but can just as easily be prepared and injected as enhanced oil recovery fluids. 

Jackson, A.C., 2006. Experimental Study of the Benefits of Sodium Carbonate on Surfactants for Enhanced Oil Recovery. M.S. thesis. University of Texas at Austin. 

Several alkaline chemicals have been employed for various aspects of enhanced oil recovery. Two of the most favorable alkaline chemicals tested and used in tertiary oil recovery are sodium orthosilicate and sodium hydroxide. Comparing their characteristics, both chemicals react with acids in crude oil to form surfactants, precipitate hardness ions and change rock surface wettability. One difference between the two chemicals is that the interfacial properties for sodium orthosilicate systems are less affected by hardness ions (13), hence slightly lower interfacial tensions would occur. Lower Interfacial tensions can aid in in-situ emulsion formation. 

A number of laboratory investigations were made into different aspects of consumption of sodium hydroxide and sodium orthosilicate in alkaline flooding of petroleum reservoirs for enhanced oil recovery. One investigation studied the role of reversible adsorption and of chemical reaction v en petroleum reservoir sands are contacted with alkaline solutiais. Another investigation studied the effect of flow rate on caustic consumption by means of a series of flow experiments through reservoir sand packs. A third series of high rate flow experiments studied changing alkaline consumption with time. 

Field results from alkaline waterflooding have thus far been very limited. However, a survey (9) of field trials that reports positive enhanced oil recovery results including Harrisburg Field, Nebraska, North Ward-Estes Field, Texas, and Singleton Field, Nebraska, all involved the use of caustic or sodium orthosilicate at concentrations of 2.0% or higher. The... 

Nonetheless, fliere was still the option of activating the natural surfactants (231, 232) that are a part of the heavy crude oil composition (probably resins and asphaltenes). This is a well-known technology in enhanced oil recovery (233-236), in which a strong base, e.g., sodium hydroxide, is used to activate flie carboxylic acids that are contained in the crude oil (237-240). 

When petroleum or kerosene (as the raw materials for gas oil or lubricants) are purified by using oleum or sulfuric acid, a reaction with the aromatic compounds takes place. While these substances were originally seen as waste products, later their chemical structures and surface-active properties were identified, thus leading to special applications for such products. Nowadays, petroleum fractions with a high content of aromatic hydrocarbons are treated with sulfur trioxide to form alkylaryl sulfonates. These products are then transformed into the sodium, ammonium or alkaline-earth salts. They are soluble in oils and therefore are of some importance as additives in lubricants, oil fuels and corrosion-inhibiting oils. Further more, they are also used as auxiliaries in production of fabrics and as dispersants in enhanced oil recovery processes. 

Polymer-surfactant systems have found wide-spread practical applications, e.g., in paints, in pharmaceutical formulations, and in systems for enhanced oil recovery. Their practical importance and the fundamental intricacies in these systems have triggei extensive studies of the interactions between polymers and surfactants, and several reviews have appeared [1-6]. The sodium dodecylsulfate (SDS)-poly(ethylene oxide) (PEO) system has been particularily well studied, both by classical [7,8] and modem methods [9-12]. 

The nature of the association maintains a locally effective shielding of the sulfonate anions within the aggregate and preservation of the clustered structure. This suggests that for these block polymer structures, the energetics of maintaining hydrophobic association are more favorable than monomer dispersion due to ionic repulsion. This was further demonstrasted by the extreme salt sensitivity of these polymers to solution ionic strength. Small amounts of sodium chloride resulted in polymer precipitation and of course loss of viscosification. This precludes the use of these particular polymers for chemically enhanced oil recovery and indicates the need for nonionic functionality to provide water solubility. To further pursue this approach acrylamide based polymers were studied. 

Alkaline inorganic chemicals such as sodium silicates, sodium hydroxides, sodium carbonate, and sodium phosphates have been added to injection fluids used in enhanced oil recovery systems. These chemicals can, in varying degrees, affect various rock and fluid parameters such as interfacial tension, interfacial viscosity, emulsion stability, rock wettability, hardness-ion content, ion-exchange capacity or equilibria, surfactant adsorption, phase equilibria, etc., in order to improve recovery efficiency for residual oil remaining after waterflooding. 

Other Anionic Carboxyiate Monomers. The anionic carboxylate monomers 8A and 9A, prepared by the Ritter reaction involving acrylonitrile or methacrylonitrile and 3,3-dimethylacrylic acid have been copolymerized in the sodium salt form to yield calcium-tolerant copoljnners with utility in enhanced oil recovery (145-148). Monomer 8A, for example, has been copol5unerized with 7A... 

Recent laboratory studies have demonstrated the potential utility of borates as alkaline agents in chemical enhanced oil recovery. Compared with existing alkalis, sodium metaborate has an unusually high tolerance toward the hardness ions, Ca + and Mg +, paving the way for the implementation of alkali-surfactant-polymer floods for the large number of high-hardness saline carbonate reservoirs. In the absence of surfactants, borate solutions exhibit a strong tendency for spontaneous imbibition, or uptake into oil-wet or mixed-wet carbonate cores, with consequently improved recovery of oil compared with solutions of other salts and alkalis. 

Uses Wetting agent, emulsifier, dispersant, rust inhibitor for cutting oils, leather oils, lube oil additives, textile oils, enhanced oil recovery, oil flotation Manuf./Distrib. Chemos GmbH Nanjing Chemlin Sodium diethylaminopropyl cocoaspartamide... 

BIO-SOFT 411-E DeMULS DLN-532CE emulsifier, enhanced oil recovery Petronate HL Petronate L Sodium didodecylbenzene sulfonate emulsifier, enteral clinical formulas CE90 GMM... 

In 1959, Wagner and Leach (11) suggested that increased oil recovery could be obtained by changing wettability of rock material from oil-wet to water-wet. Melrose and Bradner (7) and Morrow (12) also suggested that for optimal recovery of residual oil by a low interfacial tension flood, the rock structure should be water-wet. Previous investigators (13,14) have used sodium hydroxide to make the reservoir rock water-wet. Slattery and Oh (15) have shown that intermediate wettability may be less desirable than either oil-wet or water-wet rocks. Since, chemical floods satisfy many of these conditions, they have been considered promising for enhanced recovery of oil. The mechanism of oil displacement in porous media has been reviewed by Bansal and Shah (16) and more recently by Taber (17). 

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