Carbon dioxide degassing

Wang, Z.A., and Cai, W. (2004) Carbon dioxide degassing and inorganic carbon export from a marsh-dominated estuary (the Duplin River) A marsh CO2 pump. Limnol. Oceanogr. 49, 341-354. 

MORAN D (2010) Carbon dioxide degassing in fresh and saUne water. I Degassing performance of a cascade column. Aquacultural Engineering 43(1) 29-36. 

McGee KA, Doukas MP, Gerlach TM (2001) Quiescent hydrogen sulphide and carbon dioxide degassing from Mount Baker, Washington. Geophys Res Lett 28(23) 4479-4482... 

Most processes will provide for degassing (decarbonation) by means of a degasser, which provides an up-current of air through a tower filled with polypropylene packing counterflow to meet a cascade of water saturated with carbon dioxide. The degassed water collects in a sump at the base of the tower. After degassing, the C02 content is normally less than 5 ppm. 

Where silica and carbon dioxide removal is necessary, the anion unit should contain SBA (OH) resin, and the degasser should precede the anion. 

Demineralization by SAC(H)/Degassing/WBA(OH) Removes virtually all ionic TDS and carbon dioxide, but not silica. It is a cost-effective process. 

Demineralization by SAC(H)/SBA(OH) Removes virtually all TDS, including carbon dioxide and silica. The TDS in treated water is normally below 2 to 4 ppm. Conductivity is below 10 to 15 pS/cm, but this depends on the degree of sodium slip from the cation. Any slip is converted to sodium hydroxide in the anion unit (salt splitting), causing a sharp increase in conductivity and increased silica solubility. The lack of a degasser drains the anion unit capacity and requires increased caustic for regeneration. 

Demineralization by SAC(H)/Degassing/SBA(OH) Removes virtually all TDS, including carbon dioxide and silica. The degasser reduces the loading on the anion exchanger. Silica is reduced to 0.02 to 0.15 ppm Si02. 

Demineralization by SAC(H)/Degassing/SBA(OH)/MB Removes all TDS, including carbon dioxide and silica. This is a standard process where the RW is high in alkalinity and silica. The MB acts as a polisher with infrequent regeneration. Silica and sodium are both reduced to below 0.02 ppm as CaC03. Conductivity is below 0.1 pS/cm. A schematic layout of this type of plant is shown in Figure 9.3c. 

The use of degassers and FW deaerators to remove carbon dioxide gas at source. 

The feed brine of the DEP contains a large quantity of carbonates. Therefore, at pH5 carbon dioxide is degassed. When hypochlorite is added, chlorate and bromate are formed in the feed of the electrolysis cells. These reactions have a slow velocity. The result of this is that conversion is only partial ... 

In addition, a vent-gas pipe leading from the degassing tanks to the chlorine destruction unit was put in place, since addition of hydrochloric acid to the brine (pH = 5) results in the evolution of carbon dioxide and some chlorine. 

As long as the soda pop is carbonated, the carbonic acid is present along with the phosphoric acid, although at a much smaller concentration. Citric acid may also be present, but at a smaller concentration. The carbonic acid may be eliminated by degassing to remove the carbon dioxide. Your instructor may ask you to obtain titration curves (step 4 below) for both as received samples and... 

Gerlach TM, Taylor BE (1990) Carbon isotope constraints on degassing of carbon dioxide from Kilauea volcano. Geochim Cosmochim Acta 54 2051-2058 Gerlach TM, Thomas DM (1986) Carbon and sulphur isotopic composition of Kilauea parental magma. Nature 319 480-483... 

Magnesium hydroxide is commonly produced from seawater, which is rich in Mg2+ ion. The average concentration of Mg2+ in seawater is about 1,300 mg/L. The first step of the process involves removal of interfering substances from seawater, the most notable being the water-soluble calcium bicarbonate. Bicarbonate removal is crucial, as it can form insoluble calcium carbonate, a side product that cannot be separated from magnesium hydroxide readily. Acidification of seawater converts bicarbonate into carbon dioxide, which is degassed by heating. Alternatively, seawater is treated with bme to convert calcium bicarbonate to carbonate ... 

Eluent degassing is important due to trap in the check valve causing the prime loose of pump. Eoss of prime results in erratic eluent flow or no flow at all. Sometimes only one pump head will lose its prime and the pressure will fluctuate in rhythm with the pump stroke. Another reason for removing dissolved air from the eluent is because air can get result in changes in the effective concentration of the eluent. Carbon dioxide from air dissolved in water forms of carbonic add. Carbonic add can change the effective concentration of a basic eluent including solutions of sodium hydroxide, bicarbonate and carbonate. Usually degassed water is used to prepare eluents and efforts should be made... 

As a check on the degassing procedure, solubilities of carbon dioxide in aqueous calcium chloride solutions prepared in the same manner were determined at 25 °C and 1 atm. The results agreed with the previous results (4), in which the aqueous solutions were prepared by another method. Thus the degassing procedure adopted in this work can be considered satisfactory. 

Evidently less than 1/350 of the air dissolved in the sea water reaches the still. Two other types of gas could have survived the degasser—carbon dioxide and sus-... 

A simple and effective form of degassing is to hold a flask of mobile phase under a vacuum while agitating the contents in an ultrasonic bath (Fig. 3.7). The eluent is then transferred to the chromatograph for several hours of reliable operation, especially if the eluent is blanketed with an inert gas such as helium. This approach is particularly useful for clean solvents that readily absorb gases such as carbon dioxide from the atmosphere. The eluent should be degassed in the solvent storage container used for chromatography to minimize contact with the air. 

The formation of beachrock will be examined as an example of carbonate cement formation, because it has been extensively investigated and because it represents a chance to study carbonate cement emplacement under conditions where the rate of cement precipitation is relatively rapid and the associated solutions can be analyzed directly. It also differs from the cementation process in our model in that carbon dioxide can be degassed to the atmosphere, resulting in major changes in the saturation state of the cementing solution. 

Carbon dioxide continues to accumulate at the bottoms of both lakes. An international team of scientists is developing a plan to release this carbon dioxide by controlled degassing. They plan to insert long pipes deep into both lakes and suck up some of the dense bottom water. This will create a pressure difference and cause a fountain of gas-rich water to jet from the pipes. 

The sample to be analysed does not require any particular sample pre-treatment. However, in the case of musts or cloudy wines, a preliminary clarification by centrifugation or filtration is recommended in order to prevent system blockage. Carbon dioxide levels exceeding 750mg/L should be reduced or eliminated before analysis to avoid degassing of the sample in the analytical circuit. 

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