Brine standard dissolvers

In contrast to sodium chloride, langbeinite has an extremely slow rate of solution. Upon control of agitation time, essentially all the sodium chloride dissolves but most of the langbeinite remains as a soHd. Langbeinite is separated from the brine, dried, and then screened into granular, standard, and special-standard particle sizes. These fractions are marketed directiy. In one plant, the unsalable fines are used as the source of sulfate reactant for the production of potassium sulfate. 

To establish the well drainage boundaries and fluid flow patterns within the TFSA-waterflood pilot, an interwell chemical tracer study was conducted. Sodium thiocyanate was selected as the tracer on the basis of its low adsorption characteristics on reservoir rocks (36-38), its low and constant background concentration (0.9 mg/kg) in produced fluids and its ease and accuracy of analysis(39). On July 8, 1986, 500 lb (227 kg) of sodium thiocyanate dissolved in 500 gal (1.89 m3> of injection brine (76700 mg/kg of thiocyanate ion) were injected into Well TU-120. For the next five months, samples of produced fluids were obtained three times per week from each production well. The thiocyanate concentration in the produced brine samples were analyzed in duplicate by the standard ferric nitrate method(39) and in all cases, the precision of the thiocyanate determinations were within 0.3 mg/kg. The concentration of the ion in the produced brine returned to background levels when the sampling and analysis was concluded. 

A convenient method is the spectrometric determination of Li in aqueous solution by atomic absorption spectrometry (AAS), using an acetylene flame—the most common technique for this analyte. The instrument has an emission lamp containing Li, and one of the spectral lines of the emission spectrum is chosen, according to the concentration of the sample, as shown in Table 2. The solution is fed by a nebuhzer into the flame and the absorption caused by the Li atoms in the sample is recorded and converted to a concentration aided by a calibration standard. Possible interference can be expected from alkali metal atoms, for example, airborne trace impurities, that ionize in the flame. These effects are canceled by adding 2000 mg of K per hter of sample matrix. The method covers a wide range of concentrations, from trace analysis at about 20 xg L to brines at about 32 g L as summarized in Table 2. Organic samples have to be mineralized and the inorganic residue dissolved in water. The AAS method for determination of Li in biomedical applications has been reviewed . 

Lead sulphide (galena - PbS) is another likely candidate for hydrometallurgical processing particularly in the United States where, apart from the problems of the sulphur dioxide emissions, the lead toxicity problem is making it very difficult for the lead smelters to operate their conventional pyrometallurgical process and comply with EPA and OSHA standards. The total amount of lead mined in the United States is about 600,000 tons per year which, if fully converted, would yield about 100,000 tons per year of by-product sulphur. The Bureau of Mines in Reno, Nevada, have an active pilot plant study to produce lead via a hydrometal-lurigal process (2). In this process the common lead mineral galena is dissolved in an acid brine solution of ferric chloride. 

Figure 16-8 gives the density of oilfield brine at standard conditions as a function of total dissolved solids. The density at reservoir conditions is determined by dividing the density at standard conditions by the formation volume factor of the reservoir water at reservoir conditions. 

Then 500 ml. of distilled water is added and the mixture boiled for 1-2 hours to destroy excess acetic anhydride and peroxides and to remove most of the methylene chloride. The solid which separates is collected after cooling and dissolved in the combined ethereal extracts (3 x 100 ml.) from the supernatant aqueous phase. The etheral solution is washed with 5% sodium carbonate solution, water, and brine, and dried over anhydrous sodium sulfate. Evaporation of the solvent yielded 87-96 g. (80-88.5%) of crude lactone, m.p. 87-89.5°. Two crystallizations from 95% ethanol afforded 78.5-86.2 g. (73.5-80%) of fine white crystals, m.p. 93.0-94.0°. The infrared spectrum exhibited peaks at 5.78 /a (0=0), 7.65 fi and 8.60 (C—O—C). The NMR spectrum (CD,), SO (TMS internal standard at 100 MHz) showed a characteristic aromatic multiplet at 5.4-6.6 (8 H). 

Construction is of rubber-lined steel or other standard materials for the brine process. The small size of the dissolver often makes FRP (reinforced with PVC or CPVC) a good choice for the vessel, and the same resins can be used for internal piping. The saltsupporting grid can be carbon steel, but the thin screen should be of a more resistant material such as Monel. 

To Base Product A, a series of glycol ethers were added to measure foam performance in a standard blender test. The test utilized synthetic brine made by dissolving excess Allberger 3 salt into distilled water, at 90 °C. This brine is then allowed to cool to 25 °C, whereupon salt crystals precipitate out of solution. The supernatant water is then used ... 

The biodegradation of FC-171, a nonionic fluorinated surfactant, was measured by the modified ISO Standard Aerobic Shake Flask Test [21a]. The test uses nutrient salt in a brine (seawater) solution in which the fluorinated surfactant is the only organic solute. No significant biodegradation was observed after 9 days, but after 57 days, dissolved organic carbon (DOC) was reduced from 14.5 to 6.0 mg/L. Because the perfluoro chain was probably not degraded, the results indicate a 90% degradation of the oxyethylated part of the surfactant molecule. 

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