Cooling atmospheric

In heating or drying apphcations, when cooling of the product is desired before discharge to the atmosphere, cool air is blown through a second annular space, outside the inlet hot-air annulus, and released thi ough the louvers at the sohds-discharge end of the shell. 

Figure 9-99. Atmospheric cooling tower. Used by permission of The Pritchard Corp. (now, Black and Veatch Pritchard).

Figure 9-130. Atmospheric cooling tower water loss for various wind velocities. Used by permission of Plastics Technical Service, The Dow Chemical Co., Midland Mich, with data added from Fuller, A. L, et al. Chemical Engineering Progress, V. 53, No. 10 (1957) p. 501 all rights reserved.

Tryptaminefrom Tryptophan. JCS, 3993 (1%5). Place 10 g of powdered tryptophan into 500 ml of diphenyl ether and reflux for 60 min under a nitrogen atmosphere. Cool and extract with three 40 ml portions of 2 N HCl acid. Wash the extract with ether, basify with 6 N NaOH and extract with five 50 ml portions of ether. Wash the extract with water and then with a saturated NaCl solution. Dry, evaporate in a vacuum and recrystallize from benzene to get the tryptamine. 

The oil is dissolved m 500 mL of diethyl ether under a nitrogen atmosphere, cooled to -78°C in a dry ice-acetone bath and 18 g (0.11 mol) of tetrafluoroboric acid-diethyl ether complex is added dropwise by syringe over a 30-min period, while the bath temperature is maintained at -780C. The solution is allowed to warm to room temperature, and the powdery yellow solid is isolated by filtration through a 250-mL, coarse-frit, Schlenk filter tube. The product is washed several times with fresh ether and dried under a stream of nitrogen and then under reduced pressure (oil pump). The yield of salt 3 is 31-39.1 g (60-75%). The product may be used without further purification (Note 17) and may be stored under nitrogen at 0°C for several weeks with no observable decomposition (Note 18). 

A solution of 6.0 mL of borane-methyl sulfide complex (10M BH3 in methyl sulfide) in 45 mL THF was placed in a He atmosphere, cooled to 0 °C, treated with 12.6 g of 2-methylbutene, and stirred for 1 h while returning to room temperature. To this there was added a solution of the impure 3,4-diethoxy-5-methylthiostyrene in 25 mL THF. This was stirred for 1 h during which time the color deepened to a dark yellow. The excess borane was destroyed with about 2 mL MeOH (all this still in the absence of air). There was then added 11.4 g elemental iodine followed by a solution of 2.4 g NaOH in 30 mL of boiling MeOH, added over the course of 10... 

Fit a 500-ml three-necked round-bottomed flask with a sealed mechanical stirrer, attach a gas absorption device to one of the side-necks and stopper the third neck. Place 38 g (35 ml, 0.3 mol) of redistilled benzyl chloride and 150 ml of dry benzene (CAUTION) (Section 4.1.2, p. 398) in the flask. Weigh out 2g (0.015 mol) of anhydrous aluminium chloride (Section 4.2J, p. 416) into a dry capped specimen tube with the minimum exposure to the atmosphere. Cool the flask in a bath of crushed ice and add about one-fifth of the aluminium chloride. Stir the mixture a vigorous reaction will set in within a few minutes and hydrogen chloride is evolved. When the reaction has subsided, add a... 

Other than the heat of solution, heat effects that may influence absorber performance are solvent vaporization, sensible heat exchange between the gas and the liquid, and loss of sensible heat due to cooling coils or atmospheric cooling. Detailed discussion on heat effects in absorption is presented in the text by Sherwood et al. (1975). 

Readily Carbonizable Substances Transfer 1.00 + 0.01 g of finely powdered Citric Acid to a 150-mm x 18-mm (od) tube previously rinsed with 10 mL of 98% sulfuric acid at 90° or used exclusively for this test. Add 10 + 0.1 mL of 98% sulfuric acid, carefully agitate the tube until solution is complete, and immerse the tube in a water bath at 90° + 1° for 1 h. Occasionally remove the tube from the water bath and carefully agitate it to ensure that the Citric Acid is dissolved and gaseous decomposition products are allowed to escape to the atmosphere. Cool the tube to ambient temperature, carefully shake the tube to ensure that all gases are removed, and using an adequate spectrophotometer, measure the absorbance and transmission of the solution at 470 nm in a 1-cm cell. The absorbance does not exceed 0.52, and the transmission is equal to or exceeds 30%. 

Make appropriate assumptions about windage and evaporation losses and set out and solve an equation for blowdown. Windage losses will be about 1.0 to 5.0 percent for spray ponds, 0.3 to 1.0 percent for atmospheric cooling towers, and 0.1 to 0.3 percent for forced-draft cooling towers for the forced-draft towers in this example, 0.1 percent can be assumed. As for evaporation losses, they are 0.85 to 1.25 percent of the circulation for each 10-degree drop in Fahrenheit temperature across the tower it is usually safe to assume 1.0 percent, so E = AT/10, where AT is the temperature drop across the tower. Therefore, in the present case,... 

Add tris(trimethylsilyl) phosphite 18 (3.9 mL, 3.5 g, 11.7 mmol) to a two-necked round-bottomed flask (25 mL) equipped with a magnetic stirrer bar and fitted with an argon inlet, efficient water condenser and a septum under an argon atmosphere. Cool the flask in an ice bath. 

Semicontinuous deodorization with scrub cooler, barometric condenser with atmospheric cooling tower. 

Within the planet and above the surface, oxygen combined with hydrogen to form water (H2O). Enormous quantities of water—enough to fill oceans if it were liquid—shrouded the globe as an incredibly dense atmosphere of water vapor. Near the top of the atmosphere, where heat could be lost to outer space, water vapor condensed to liquid and fell back into the water vapor layer below, cooling the layer. This atmospheric cooling process continued until the first raindrops fell to Earth s surface and flashed into steam. 

Retallack [2] computed relative acidification for the Brownie Butte boundary bed by using the impact bed as the parent material, and obtained a value of 0.054 meq cm. Since typical late Cretaceous/early Paleocene paleosols have acid consmnption rates of 0.01-0.02 meq cm yr" , this is evidence for enhanced leaching from the boundary bed relative to the impact bed. Because the boundary bed was emplaced -minutes to hours after tlie impact [33] and the bulk of the impact bed (including shocked quartz) was emplaced -hours to days after tlie impact bed, the boundary bed may have experienced somewhat greater acid deposition. This was true only if significant acid deposition occurred in tlie interval between boundary and impact bed emplacement. In the normal atmosphere rainout of acid in the troposphere occurs on timescales of days in the post-impact atmosphere rainout may have occurred soon after the unpack once the atmosphere cooled. Because of the uncertainties in such timescales and the possibility of different parent material compositions for the impact and boundary beds, we do not consider tlie relative acidification of the two beds further. 

In heating or drying applications, when cooling of the product is desired before discharge to the atmosphere, cool air is blown through... 

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