Stripping of gases

The O Connell correlation was based on data for bubble-cap trays, and it was stated (131) to predict 90 percent of the efficiency data within 10 percent, both for distillation and absorption. For sieve and valve trays, its predictions are likely to be slightly conservative (151). Ludwig (4) warns that O Connell s absorber correlation (Fig. 7.55, sometimes predicts efficiencies that are too high He believes that it can be used for stripping of gases from rich oils and for absorbers provided care is exercised not to accept too high values. 

Stabiliser. The control objective is the stripping of gases from liquid, but with minimum loss of benzene. A suitable control structure is ... 

Mass-transfer theory indicates that for trays of a given design the factors most hkely to inflnence E in absorption and stripping towers are the physical properties of the flnids and the dimensionless ratio Systems in which the mass transfer is gas-film-controlled may be expected to have plate efficiencies as high as 50 to 100 percent, whereas plate efficiencies as low as 1 percent have been reported for the absorption of gases of low sohibility (large m) into solvents of relatively high viscosity. 

Extractive Stripping of Inert-Rich Hydrocarbon Gases with a Preferential Physical Solvent. U.S. Patent 4,680.042, Jul. 14, 1987. 

MS As are recirculated. The stripped acid gases are fed to a Claus unit" where elemental sulfur is recovered from hydrogen sulfide. In view of air pollution control regulations, the tail gases leaving the Claus unit, R, should be treated for partial removal of the unconverted hydrogen sulfide. Table 3.10 summarizes the stream data. 

Abblasehahn, m. blowoff cock, abblasen, v.t. blow away, blow off, blow blast (castings) distil off. — v.i. (of gases) expand. Abblaseventil, n. blowoff valve, abblassen, v.i. fade, lose color, grow pale, abblattem, v.r. i. scale off, exfoliate desquamate shed the leaves. — v.t. descale strip of leaves. 

Gas-fired water heaters use the same general method of construction, except that the elements are replaced with a burner beneath the tank. The combustion products from the burner are vented through a flue made out of the same thickness steel as the tank, that goes up through the center of the tank. To increase heat transfer from the hot flue gases to the inner wall of the flue, a baffle is inserted down the flue. This baffle is a twisted strip of sheet metal with folds and tabs on it. The folds and tabs are designed to... 

The mixture to be separated is fed to the centre of the column down which activated carbon moves slowly. Immediately above the feed, the rising gas is stripped of ethylene and heavier components leaving hydrogen, methane and any non-adsorbed gases to be discharged as a top-product. The adsorbent with its adsorbate continues down the column into an enriching section where it meets an upwards stream of recycled top-product. The... 

These results are not unlike those reported by others, for separation of gases with molecular sieves. For example, when HgS is stripped from natural gas with a Davison 5A molecular sieve, the reaction front is typically 1 to 5 feet at superficial gas velocities of 15 to 30 feet per minute (lO). From this perspective, the operation of a hydride-hydrogen separation system is similar to conventional units. 

The specimen, most suitable for such measurements, is shown schematically in Fig. 1.8. The upper part of the specimen is used for comparison. To prevent the interaction of components A and B in this part, a thin barrier layer of some substance which does not react with both A and B under chosen experimental conditions is deposited. The position of the layer interfaces is measured at certain moments of time relative to the inert markers located at the initial interface between substances A and B and/or inside the ApBq layer. Microhardness indentations onto the specimen cross-section surface, thin wires and strips of chemically inert materials, bubbles of inert gases, etc., can serve as the markers (for more detail, see for example Refs 35, 124). 

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