Calcium sulfate scale inhibitors

Calcium carbonate/calcium sulfate scale inhibitor Friction reducer... [Pg.82]

PCA 16 is particularly effective for control of calcium sulfate deposition (and thus finds application, under different brand names and grades, as a calcium carbonate/sulfate scale inhibitor for RO systems treating brackish waters). This inhibitor is also useful for calcium phosphate control. It is stable against chlorine. [Pg.160]

In general, SS/MA and the other calcium phosphate inhibitors are not as good at inhibiting calcium carbonate scale as PMA or HEDP or as good at inhibiting calcium sulfate scale as PMA and 2000 MW PAA. [Pg.165]

Uses Scale inhibitor, dispersant esp. of calcium carbonate and calcium sulfate scales... [Pg.717]

The formation of calcium carbonate (CaCOs), calcium sulfate, and barium sulfate scales in brine may create problems with permeability. Therefore it is advantageous that newly made fractures have a scale inhibitor in place in the fracture to help prevent the formation of scale. Formulations of hydraulic fracturing fluids containing a scale inhibitor have been described in the literature [1828]. [Pg.264]

Earlier the standard industrial approach to prevention of calcium carbonate scaling by addition of sulfuric acid was described. Objectives were to reduce bicarbonate alkalinity, convert calcium carbonate to calcium sulfate, and regulate sulfate concentration by bleedoff. Corrosion inhibitors were added to protect system metals. A new approach to industrial cooling system treatment does not require addition of sulfuric acid. It involves application of phosphonate seques-trants, dispersants and special corrosion inhibitors, and provides deposit control equal to that obtainable when using sulfuric acid. Availability of phosphonate sequestrants makes possible combination scale control and corrosion inhibitors that can be used without the necessity of reducing cooling water alkalinity by acid feed. [Pg.361]

Phosphorus-containing polymers, especially those comprising vinylphosphonic acid (VPA) and vinylphosphonate moieties, have become attractive polymers on an industrial scale, due to their various applications based on the properties of the phosphonic group. In early applications, poly(VPA) and its derivatives were noted as efficient scale inhibitors in cooling and boiler water systems, by inhibiting the formation of calcium sulfate, carbonate, and phosphate and as flame retardants." ... [Pg.67]

NACE Test Methods for Determining Water Quality for Subsurface Injection Using Membrane Filters (TM0173) describes methods for evaluating water quality of injection water, NACE Test Methods for Laboratory Screening Tests to Determine the Ability of Scale Inhibitors to Prevent the Precipitation of Calcium Sulfate and Calcium Carbonate from Solution (for Oil and Gas Production Systems) (TM0374) is used to rank order scale inhibitors at 158°F (70°C). [Pg.817]

It may be advisable to include a calcium scale inhibitor in the acid stages or the overflush if treating either a well containing a high sulfate ion concentration (>1,000 ppm) in the formation water or a formation containing an appreciable carbonate mineral phase. Scale inhibitors include phosphonates, sulfonates, and polyacrylates. There are also certain proprietary acid systems containing acids that may inhibit sulfate scale formation. Scale inhibitor chemical compatibility must alwa) be demonstrated. [Pg.92]

Phosphonate scale inhibitor for sulfate scale situations. It prevents formation of calcium, strontium and barium sulfate scale, as well as calcium carbonate. [Pg.191]

Chem. Descrip. Carboxylate/sulfonate/nonionic functional terpolymer Uses Scale inhibitor, dispersant for cooling water systems dispersant for CaCOj, calcium sulfate, calcium phosphate, and clay iron oxide and zinc stabilizer sludge conditioner for boiler water treatment in refinery plants, chem. plants, drilling oil, steel mills, etc. [Pg.791]

Chem. Descrip. Polyacrylates and polymaleic polymers Uses High performance scale and deposit control agents for boiler and cooling water systems provides effective scale control over wide range of pH, temp., and hardness ranges effective with both hard or soft feedwaters provides protection from calcium carbonate and calcium sulfate exc. dispersant for calcium phosphate, iron oxides, and other inorg. solids designed to be used in conjunction with corrosion inhibitors... [Pg.1346]

Uses Effective scale Inhibitor for control of calcium carbonate, barium sulfate, and calcium sulfate for oil field prod. [Pg.1384]

Thennodynamic inhibitors are complexing and chelating agents, suitable for specific scales. For example, for scale inhibition of barium sulfate, common chemicals are ethylenediaminetetraacetic acid (EDTA) andnitrilotriacetic acid. The solubility of calcium carbonate can be influenced by varying the pH or the partial pressure of carbon dioxide (CO2). The solubility increases with decreasing pH and increasing partial pressure of CO2, and it decreases with temperature. [Pg.104]

Early antisealants used sodium hexametaphosphate (SHMP) as a threshold agent to inhibit the growth of calcium carbonate and sulfate-based scales.6 Most antisealants on the market today contain sulfonate, phosphate, or carboxylic acid functional groups. Perhaps the most effective antisealants today contain and blend of polyacrylic acid (PAA) and phosphoric acid or polyacrylate and a hydroyethylidene diphosphonate (HEDP).12 The polyacrylate-HEDP blends also claim to have good dispersion qualities toward silts and clays.12 Some new inhibitors include a chelant and disper-ant to keep suspended solids such as iron and manganese oxides in solution. These newer antisealants are generally more effective than SHMP for a variety of potential scales.6... [Pg.178]

Uses Corrosion inhibitor and deposit control agent in cooling water treatment preventing the development and accumulation of calcium carbonate, sulfate and phosphate scales... [Pg.432]

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