Columns irrigated

In the experiment pure CO2 at 1 atm was bubbled into a packed column irrigated by rapidly recirculating solution kept at 20°C and close to constant Cg. Find the fraction of entering CO2 absorbed. 

I. Iliuta, F. Larachi, Mechanistic model for structured-packing containing columns Irrigated pressure drop, liquid holdup and packing fractional wetted area, Ind. Eng. Chem. Res. 40 (2000) 5140-5146. 

Fig. 4.7.7. Chromatography of a crude yeast extract on Cibacron Blue F3G-A silica with on-line monitoring of hexokinase (HK) and 3-phosphoglycerate kinase (PGK) activity. Sample applied at first arrow crude yeast extract (2 pi) column irrigant, 0.1 M Tris-HCI buffer (pH 7.3) containing O.S mM EDTA, 5 mM MgClj and O.S mM 2-mercaptoethanol flow rates, I ml/min, both pumps post-column reactor temperature, 40 0.1°C assay mix temperature, 0°C temperature of analytical column, 22°C eluents (400 pi), as indicated by the arrows UV-detector (290 nm), 0.32 AUFS enzyme activity detector, 0.5 AUFS. Reproduced with permission from Ref. 126.

Gel permeation. Bio-Gel A-5m (57 x 2.5 cm column) was equilibrated in the appropriate buffer and packed in a column. Three ml sample of membranes was applied to the top of the column and the column irrigated with 40 Tris-HCl-40 mM NaCl-0.24% deoxy-cholate (DOC) at a flow rate of 10 drops min". Fractions containing 100 drops (approximately 1.7 ml) were collected. 

C. Liquid Distributor (see Figures 4-9). According to Strigle, This is the most important column internal from a process standpoint. A liquid distributor is required at all locations in the tower where an external liquid stream is introduced. High-performance distributors provide a flow rate variation per irrigation point that is a maximum of 5% of the average flow. The geometric uniformity of... 

Riesel-feld, n. field irrigated with sewage, -hohe,/. packing depth (of a tower). -jauche, /. sewage (as a fertilizer), -kolonne,/. trickling column, -kiihler, m. spray cooler, trickling cooler. 

A new generalised correlation for pressure drop in packed columns, similar to Figure 11.44, has been published by Leva (1992), (1995). The new correlations gives a better prediction for systems where the density of the irrigating fluid is appreciably greater than that of water. It can also be used to predict the pressure drop over dry packing. 

Figure 5.8 shows such a system we call it a Soxhlet apparatus. Solvent is passed continually through a porous cup holding the ground coffee. The solvent removes the caffeine and trickles through the holes at the bottom of the cup, i.e. as a solution of caffeine. The solvent is then recycled solvent at the bottom of the flask evaporates to form a gas, which condenses at the top of the column. This pure, clean solvent then irrigates the coffee a second time, and a third time, etc., until all the caffeine has been removed. 

However, as far as we know, the distribution of LAS biodegradation intermediates according to depth in the sediment column has been determined only in marine sediments [58]. This study was performed in a saltmarsh channel (Sancti Petri Channel, Cadiz Bay, Spain), receiving untreated urban wastewater effluents. In this zone the benthic organisms are very scarce [59], and the capacity for irrigation of... 

Fig. 8.26 Exchangeable sodium percentage (ESP) along a Burleson soil column, as a function of the sodium adsorption ratio (SAR) of irrigation water. The values were obtained by percolating the soil columns with sodic water (total electrolyte concentration of 11 meq/L). Each curve corresponds to a given applied volume of solution (Thomas and Yaron 1968)...

Huysman, F. Verstraete, W. (1993b). Water-facilitated transport of bacteria in unsaturated soil columns influence of inoculation and irrigation methods. Soil Biology Biochemistry, 25, 91-7. 

The steam may be purified by Droplet Separation techniques such as knitted wire mesh demister pads, wave plate separators and fiber pad separators using PTFE fibers. It can also be purified by scrubbing devices such as packed columns, venturi scrubbers, and irrigated sieve plates. Sometimes a combination of Droplet Separators and Scrubbers are used because AN emissions from neutralizers are very difficult to remove due to the very fine particles103. 

Because the irrigation rate in vacuum columns often falls below 1000 lb/(h)(ft2), it may be wise to add another 6 in to the listed HETP values as a safety factor. For the ethylbenzene/styrene system... 

In step 1, the column-diameter-to-packing-size ratio for Raschig rings can be less than 30 for scrubbing applications in which the liquid-irrigation rate is high and the column is operated at above 70 percent of flooding. 

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