Sparge vessels

Volatilised tin species were trapped from the same or replicate water samples following rapid injection of aqueous, excess sodium borohydride solution directly into the P/T sparging vessel immediately prior to beginning the P/T cycle. 

Chang B-J, Chian E S K (1981) A model study of ozone-sparged vessels for the removal of organics from water, Water Research 15 929-936. 

Air-water-(glass beads) Power-to-volume ratio Gas-sparged vessel with Physical system Wiedmann et al. 

PUJ-1 After reading the article Designing gas-sparged vessels for mass transfer [Chem.Eng., 89(24), p. 61 (1982)], design a gas-sparged vessel to saturate 0.6 mVs of water up to an oxygen content of 4 X 10" Itg/m at 20°C. A liquid holding time of 80 s is required. ... 

The gas may be sparged through the liquid as a stream or cloud of bubbles (bubble columns, plate columns, and sparged vessel). 

The holdup for sparged vessels can be correlated through the slip velocity by the following equation developed from data presented by Hughmark (1967) ... 

Chapman CM, Nienow AW, Middleton JC. (1980) Surface aeration in a smaU agitated and sparged vessel. Biotechnol. Bioeng., 22 981-994. 

All experiments were conducted with pasteurized 2% fat milk acquired from a local dairy. The milk was homogenized in two stages at 2500/500 psi. UHT processing was accomplished with a plate heat exchanger unit at 144.4 °C for 4 seconds. Flow rate was 2000 ml/min. Samples were collected in sterile stainless steel vessels. Aliquots were asepticaUy transferred to 250 ml amber bottles and sealed with teflon lined lids. For volatile ctmtmt analysis, 10 ml of UHT milk was transfored to a 100 ml sparging vessel and treated as described previously. 

Takahashi, K., McManamey, W.J., Nienow, A.W., Bubble size distributions in impeller region in a gas-sparged vessel agitated by a Rushton turbine, J. Chem. Eng. Jpn. 25(4) (1992), 427-432. 

Deshpande and Barigou [14] have tabulated a useful summary of the many published empirical studies of defoaming using various rotary devices. In Appendix 7.1, Table 7.A1, we produce an updated version of that table where later studies are included and an error in a citation is rectified. Whether performance has been studied in either bubble colunms or stirred vessels is indicated. Most of the reported studies are at laboratory scale, concerned with controlling the foam of dilute aqueous surfactant solutions in sparged vessels of <0.5 m diameter. Only two reported studies concern pilot scale with practical systems—Kraft (paper) mill effluent [15] and recombinant Bacillus fermentation [16]. 

The gas hold-up in three phase sparged vessels depends on the gas velocity, but, just as in liquid-gas systems, different regimes must be distinguished (uniform bubbling, churn-turbulent flow, slugging etc.). Data with high slurry concentrations are scarce. If two phase relations will have to be applied for high slurry concentrations then the fluid properties should probably be replaced by liquid solids suspension properties. 

Solid/llquid mass transfer in both sparged vessels and stirred vessels can be successfully described with the energy input concept. Direct relation with fluid-particle slip velocities could reveal influence of geometrical factors not covered by the energy input concept. Probably, in stirred vessels the influence of the gas phase can not be completely accounted for by the total energy input/m liquid concept. However, data on this aspect are relatively scarce and more work is needed to clarify this aspect. 

These equations are for operation at ambient temperatme. In the fully turbulent regime there is a dependence of void fraction on temperatme which is discussed below. This gives ([) a Measmements of the void fraction distribution in gas-sparged vessels clearly show a region of high gas fraction in the violently... 

The gas-liquid mixture can be mechanically agitated, as with an impeller, or, as in the simplest design, agitation can be accomplished by the gas itself in sparged vessels. The operation may be batch, semibatch with continuous flow of gas and a fixed quantity of liquid, or continuous with flow of both phases. 

The holdup for sparged vessels, correlated through the slip velocity, is shown in Fig. 6.2. This is satisfactoiy for no liquid flow ( = 0), for cocurrent... 

Figure 62 Slip velocity, sparged vessels. (G. A. Hughimrk, Ind. Eng. Chem. Process Des. Deo., 6,218 (1967), with permission of the American Chemical Society.]...

In tray towers, entrainment of liquid in the gas is a form of back mixing, and there are back mbcing and axial mixing on the trays, which we have already considered. In sparged vessels, the liquid is essentially completely back-mixed to a uniform solute concentration. Both phases are largely completely mixed in mechanically agitated vessels. 

Calculate the power imparted to the vessel contents by the gas in the case of the sparged vessel of Illustration 6.1. 

A gas or vapor in a gas can be adsorbed on a solid which is slurried in a liquid. For example, sulfur dioxide can be adsorbed from a mixture with air on activated carbon slurried in water [8]. This procedure was suggested as early as 1910 [25], but interest in it has revived only recently. The reported details thus far are confined to laboratory studies of sparged vessels [73, 88] operated semibatch (gas flow continuous, sluny batch) or cocurrent flow or both [66]. A continuous countercurrent process has been described [4, 27]. The slurry is of course much easier to handle than dry solid, and it has been shown that the capacity of the slurried adsorbent is about the same as for dry solid [73], much larger than that of the liquid solvent alone [96]. 

Autosampler Tekmar ALS 2016 With 25 mL frit sparge glass vessels for water, needle sparge vessels for soil samples... 

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