Brine evaporation

Werk, n. work works apparatus, mechanism (Salt) brine evaporated at one time (Metal.) pig of raw lead (Paper) stuff, -anlage, /. plant, works work, equipment, -blei, n. raw lead (usually containing silver), -bot-tich, m., -butte,/, (Paper) stuff vat. -fuhrer, m. foreman. -leitung, /. management, -leute, pi. workmen, hands, -meister, m. foreman, -probe, /. (Metal.) sample of... 

The fra/i.s-but-2-cn-1,4-dionc (8.4 mmol) and the methylene compound (8.4 mmol) are stirred with Na2CO, (98 mg) and TEBA-CI (20 mg) in PhH (10 ml) at 75-80°C until the reaction is complete, as shown by TLC analysis (ca. 24 h with P-keto esters and ca. 48 h with cyclohexa-l,3-dione). Et20 (50 ml) is added and the organic phase is washed well with brine. Evaporation of the ethereal solution gives the unstable adduct but, if the etheral solution is saturated with HC1 gas, the adduct is converted into the furan (overall yields >45%). 

The first oil wells were drilled in China in the fourth century, or perhaps earlier. The wells, as deep as 243 m, were drilled using bits attached to bamboo poles. The oil was burned to produce heat needed in the production of salt from brine evaporation. By the tenth century, extensive bamboo pipelines connected oil wells with salt springs. Ancient Persian tablets also indicate the medicinal and lighting uses of petroleum in the upper echelons of their society. 

Fresh feed from stream 1 combines with recirculated brine from stream 13 and the combined stream, 14, enters the main heat exchanger, where sensible heat is added, but no vaporization occurs because the pressure is maintained slightly above the vapor pressure. All vaporization occurs in the flash tank and the vapor is compressed and desuperheated and becomes the heating medium for the main exchanger. As only a small fraction of the brine evaporates (around 0.005) the majority is recirculated as stream 13, the remainder being discarded in 8. 

A mixture of the decalone 1 (40.8 mg, 196 pmol) and MCPBA (127 mg, 80%, 589 pmol) was left to stand at room temperature for 8 h and at 60 °C for 12 h. The resulting mixture was diluted with EtOAc and the organic layer was washed with sat. NaHC03 (2 x), water and brine. Evaporation of the solvent followed by MPLC purification of the residue (EtOAc-n-hexane, 1 10) gave lactone 2 (31.5 mg, 72%) as a colorless oil. 

Fig. 16.11 A chloride concentration cross-section, Gerald City. Leakage from the brine evaporation pit is recognizable. The heavy brine accumulated above the shale aquiclude. (From Fryberger, 1975.)...

Salts from evaporative brines, evaporative lake sediments. 

Bottomley D. J., katz A., Chan L. H., Starinsky A., Douglas M., Clark I. D., and Raven K. G. (1999) The origin and evolution of Canadian Shield brines evaporation or freezing of seawater New lithium isotope and geochemical evidence from Slave Craton. Chem. Geol. 155, 295-320. 

In the reverse osmosis stage of the plant, the water passes through the membranes and is again separated into two streams one with a high salt concentration destined for the brine evaporation stage and the other clarified, which is directed to a tank of clean water mixture, where other streams of the process meet. 

FIGURE 6.2 Forced circulation evaporator such as used for simultaneous brine evaporation-crystallization. Mechanical movement of brine past the heat-exchange surface avoids decreased heat transfer efficiency from crystallization on this surface. Constructed of Monel or Monel-clad steel for parts contacting brine. (Reprinted from Kirk-Othmer [10], with permission.)... 

The brine evaporation investigation was conducted under different conditions few different brines ... 

A mathematical model was established for the evaporation of high mineralized brines to permit management of the concentration processes in the effluents in the reservoir in relationship to the rate of the brine evaporation at the Nebitdag iodine plant. The elasticity of the water stream over the brines at different concentrations and at different temperatures (10, 15, 20, 25, and 30 °C) was identified. The data was processed using a computer by the method of the least squares and the deduction of an equation for the calculation of the elasticity of the vapor above the brines during different degrees of concentration in the temperature interval from 5 to 35 °C. 

PCC on alumina (neutral) [1230 g = 1.0 mol Cr(VI)] is suspended in 1500 mL of hexane and the mixture of isopulegols described above (60 g, 0.39 mol) in 300 mL of hexane is added in one portion. The heterogenous mixture is stirred for 14 h at r.t., and the absorbed reagent is separated and washed five times with 250-mL portions of Et20. The solvent is removed (attention the isomeric isopulsgones are extremely volatile oils). The crude mixture is dissolved in 450 mL of EiOH and treated with 1.0 g of NaOH. The mixture is heated for 1 h, and the EtoH is removed under reduced pressure. The residue is partitioned between 320 mL of Et20 and 150 mL of H20. The separated ethereal layer is washed with 10% HCl and brine. Evaporation of the solvent and distillation of the residue gives the product yield 51.8 g(88%) bp 43 JC/0.0l Torr, [a] 0 —23.0 (neat). 

ICBs to a clarifier for separation into sludge and overflow streams (Parsons, 2000e). The sludge was to be dewatered in filter presses and sent off site to a landfill. The filtrate from the filtration step was to be combined with the clarifier overflow, and the eombined stream (about 100 gallons/min) was to be sent to a brine evaporator. The distillate, about 90 percent of the feed, was to be recycled as process water. The bottoms were to be sent to an evaporator/crystallizer for additional water recovery and the crystallized salts sent off site for disposal the distillate was to be added to the recycled process-water sheam. However, EDS test results showed that (1) the clarifier is not needed, (2) the bioreactor effluent can be recycled without clarification, and (3) a slipstream can be sent to the evaporator for removal of salts and sludge. Vented air from the ICBs can be sent to the off-gas treatment system (Parsons, 2000e). 

Natural salts are often processed to remove some of their impurities before sale. All food-grade and certain chemical applications require this. In the chlor-alkali industry, it is necessary at some point to convert crade salt as mined or produced into a material suitable for use in electrolysis. Whether this occurs at the salt producer s site or in the chlor-alkali plant is fundamentally irrelevant. For economic or technical reasons, the salt supplier often undertakes a certain amount of upgrading. The most important processes are salt washing, brine evaporation, and salt recrystallization. 

In-process economization also would reduce the amount of heat to be transferred in the evaporators themselves. There would be less steam required and, along with it, less heat-transfer surface. In any event, adding more effects and reducing the available temperature drop eventually becomes counterproductive. One rule of thumb is that it is seldom desirable to use an effective temperature drop of less than five or six degrees in each stage [25]. In brine evaporation, consideration of all these factors usually leads to a design containing three to six effects. 

G. Materials of Construction. Evaporator materials of construction and their costs play a large role in determining the optimum compression ratio. Monel is a standard material of construction for brine evaporator bodies. Stabilized titanium (e.g.. Grade 12) is a frequent choice for heater tubing and Type 316 stainless steel for the circulating pumps. The evaporator normally will be of the forced-circulation type described in Section 9.3.3.2. It will either contain a number of effects or operate with vapor recompression. Salt-recovery centrifuges may be Monel or stainless steel. 

In membrane-cell plants fed with well brine, evaporation of depleted brine can be used to remove the excess water and maintain a water balance. This approach does not require a crystallizing evaporator. The solids-recovery section of a salt evaporator also is not required, and evaporator design is simpler. However, the problem of sulfates in the brine remains, and the materials of construction mentioned above may not be suitable. Free chlorine should be scrupulously removed from the depleted brine before it enters an evaporator, and even the chlorate that forms in the cells can be a problem. The working materials may have to be upgraded to types with higher nickel contents. Thus, the evaporator bodies and liquor-handling components may be upgraded from Monel to one of the Incoloys, which contain about 20% chromium and up to 45% nickel. 

When membrane cells operate in tandem with mercury or diaphragni cells, there is an opportunity to purge sulfate by sending at least part of the depleted brine that otherwise would be recycled to the other cells. This approach is less effective with mercury cells. The water balance is extremely tight in a mercury-cell plant, and any import of water must be balanced by an export. Since export would spread the potential for mercury pollution, we reject it as an operable solution. Only merciuy-cell plants with some capacity for addition of water to the brine loop, as for example a plant with a brine evaporator, could be integrated in this way. 

T.H. Yohe, Use of Salt/Brine Evaporators in Brine-Fed Membrane Cell NaOH Plants, 30th Chlorine Institute Plant Operations Seminar, Washington, DC (1987). 

Multiple-Effect Evaporation. The discussion of brine evaporation in Section 7.1.5.2A showed how installing a number of effects and using process vapor as a source of heat reduces the amount of energy that must be added to the process. The boiling point rise (BPR) of brine solutions makes some of the available temperature potential useless as a driving force for heat transfer. This limits the number of effects and the achievable steam economy. Similar limitations exist in caustic evaporation but are much more severe. 

In any event, there is a need to bring together the salt produced and the stream requiring saturation. The usual approach is to transport the salt as a slurry to the appropriate brine system. In an all-diaphragm plant, the carrier fluid may be treated brine, evaporator condensate, or a mixture of the two. Condensate dissolves much of the salt and therefore reduces the size of the stream to be transferred. In a combined plant, the transfer fluid is the depleted and dechloiinated brine from the non-diaphragm cells. 

For the thermodynamic non-equilibrium phase diagram of the sea water system as called "solar phase diagram" in the first, N.S. Kurnakov (1938) was in the first to report the experimental diagrams based on the natural brine evaporation, and further called... 

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