Entrance effect and gas-film mass-transfer coefficient in a large-diameter packed column

Journal Article · Sat Apr 01 04:00:00 EST 2000 · Industrial and Engineering Chemistry Research

DOI:https://doi.org/10.1021/ie990604f· OSTI ID:20062647

Doan, H D; Fayed, M E

The effects of the bed height and the entrance section below the packing support on mass transfer in a 1.2-m diameter packed bed of 50-mm ceramic Intalox saddles were investigated under various gas flow rates from 1,957 to 7,828 kg/h {sm_bullet}m{sup 2} and liquid flow rates from 12,200 to 46,700 kg/h {sm_bullet}m{sup 2}. The entrance effect accounted for 17% of the overall water vapor transferred from moist air to a calcium chloride solution in the tower, regardless of the packing height. For a 0.91-m high bed, the average mass-transfer coefficient was directly proportional to the gas rate and was proportional to the liquid rate to the power of 0.24. For a 1.8-m high bed, the average mass-transfer coefficient was proportional to the gas rate to the power of 0.89 and appeared to be independent of the liquid rate. The height of a transfer unit (HTU) for 50-mm ceramic Intalox saddles remained relatively constant under various gas rates used in the present study. The HTU was about 0.5 m for the short bed and 0.8 m for the tall bed.

• Research Organization: Ryerson Polytechnic Univ., Toronto, Ontario (CA)
• OSTI ID: 20062647
• Journal Information: Industrial and Engineering Chemistry Research, Journal Name: Industrial and Engineering Chemistry Research Journal Issue: 4 Vol. 39; ISSN IECRED; ISSN 0888-5885
• Country of Publication: United States
• Language: English

Related Subjects

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION
CHEMICAL INDUSTRY
DESIGN
EXTRACTION COLUMNS
MASS TRANSFER
PACKED BEDS
PARAMETRIC ANALYSIS