Alkaline-surfactant-polymer-foam

The focus of more recent work has been the use of relatively low concentrations of additives in other oil recovery processes. Of particular interest is the use of surfactants (qv) as CO2 (4) and steam mobiUty control agents (foam). Combinations of older EOR processes such as surfactant-enhanced alkaline flooding and alkaline—surfactant—polymer flooding show promise of improved cost effectiveness. 

The initial oligomer as an aqueous solution is obtained from the reaction of urea and formaldehyde at 100°C and pH = 5.8-6 [130]. The process of polycondensation occurs in the presence of acidic catalyst and yields a tri-dimensional polymer, releasing water and formaldehyde [131]. Surfactants are added as foaming agent to the initial composition for the formation of urea polymer foams [125,130]. Various additives are employed to improve the sanitary properties of these plastics. For example, ammonium carbonate reduces the content of free formaldehyde, while addition of carbonates of alkaline metals inhibits corrosion [125]. 

The type of polymer obtained depends on factors such as the pH and temperature of reaction, the ratio of melamine to formaldehyde, and the type of catalyst employed. For decorative laminates, melamine-formaldehyde is prepared by reacting melamine in stainless steel kettles under reflux, alkaline conditions with 37% to 46% formaldehyde in aqueous solution. The reaction temperatures used vary from 80 to 100°C and are maintained until the condensation has reached the desired end point—that is, reacted sufficiently but still water-soluble. The end point is checked by measurements of viscosity, cure time, and water tolerance. Depending on the type of laminate to be produced, other constituents (surfactants, plasticizers, release and anti-foam agents) normally are added to the base resin before impregnation of the surface papers. It is common practice also at this stage to adjust the pH by adding acid catalysts. 

Chemical flooding polymer, deep-formation profile control using gels, surfactant, alkaline, emulsion, foam, and their combinations... 

This book focuses on chemical EOR processes, including alkaline (A), surfactant (S), polymer (P), and any combination of these processes. We discuss emulsion whenever it relates to any chemical processes. In addition, we briefly describe foam when presenting an application of ASP with foam. Emulsion and foam are more related to mobility control. These two processes are not discussed in detail because they are thermodynamically unstable processes quite different from the stable processes we deal with here. Rather, we discuss the general mobility control requirement in EOR processes in Chapter 4. 

The majority of polymers, used as additions to concrete, contain the stabilizing admixtures, being the non-ionic surfactants. They may include also the anti-foaming agents. It should be additionally remembered that the polyesters, as poly(vinyl acetate) may hydrolyze in the strongly alkaline environment of concrete. 

Features Rec. for use alone or in combination with syn. lubricant components such as functional fluids, block polymers, low-foam surfactants, sulfated esters, etc. low foaming hard water stable contains P alkaline compat. 

Uses Surfactant in alkaline, low foam powdered laundry, and all puqiose detergents metal cleaners and brighteners detergent sanitizers hard surface, floor, wateriess hand and acid tile cleaners xylene emulsifier emulsion polymerization pesticide emulsifier dedusting agent fc -pkg. adhesives, paper, polymers defoamer in food-contact paper/paperboard emulsifier in reifg. of food-contact articles... 

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