Packed-Tower Design

Effects of System Physical Properties on Ug and Ui When designing packed towers for nonreacting gas-absorption systems for... 

Traditional Design Method The traditionally employed conventional procedure for designing packed-tower gas-absorption systems involving chemical reactions makes use of overall volumetric mass-transfer coefficients as defined by the equation... 

Packed columns are gaining ground on trayed columns. Lieberman states that based on his design and operating experience, a properly designed packed tower can have 20-40% more capacity than a trayed tower with an equal number of fractionation stages. 

Counce RM, Perona JJ. Designing packed-tower wet scrubbers emphasis on nitrogen oxides. In Cheremisinoff NP, ed. Handbook of Heat and Mass Transfer. Vol. 2. Houston Gulf, 1986 953-966. 

R. M. Counce, J. J. Perona, Designing Packed-Tower Wet Scrubbers Emphasis on Nitrogen Oxides, in Handbook... 

MOC. Strigle et al. (15,57,97) recommended designing packed towers with a 10 to 20 percent margin from the maximum operational capacity (MOC). Since the MOC iB usually about 5 percent below the flood... 

Effects of System Physical Properties on kG and kL When designing packed towers for nonreacting gas-absorption systems for which no experimental data are available, it is necessary to make corrections for differences in composition between the existing test data and the system in question. The ammonia-water test data (see Table 5-24-B) can be used to estimate HG, and the oxygen desorption data (see Table 5-24-A) can be used to estimate HL. The method for doing this is illustrated in Table 5-24-E. There is some conflict on whether the value of the exponent for the Schmidt number is 0.5 or 2/3 [Yadav and Sharma, Chem. Eng. Sci. 34, 1423 (1979)]. Despite this disagreement, this method is extremely useful, especially for absorption and stripping systems. 

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