Column packings Dixon rings

The experiments were conducted in an absorption column, which is made of acrylic plastic and enwrapped by thermal insulation material. A Dixon ring (made of 304 stainless steel) was filled into the column. In order to minimize the unlavorable effect of wall flow, a liquid re-distributor was placed in the middle of packed bed. Besides the packed column, auxiliary equipments including air compressor, CO2 cylinder, gas mass flow meter with 1% accuracy (model CS200, Beijing Sevenstar Electronics Co., LTD), constant liquid-flow pump with 0.3% accuracy (model BTl-300, Shanghai Qi Te Analytical Instruments Co., LTD), thermostatic water bath with 1 K (model HHS-11-... 

In this paper, the mass transfer experiments of the absorption of CO2 in aqueous MEA and DETA solutions were carried out in a laboratory using randomly Dixon ring packed columns. The absorption performance was evaluated in terms of overall mass transfer coefficient Kqg ). The predictive correlation proposed by (Kohl and Nielsen, 1997) [4] for predicting the Kqo of MEA can be applied to a packed column containing a Dixon ring with an AAD of 14%. A new mass transfer correlation was successfully developed for predicting in DETA-CO2 absorption with an AAD of 16%. 

An excellent but expensive packing for columns consists of Dixon gauze rings. They are small gauze rings of Lessing shape made of Staybrite (stainless steel) gauze. A useful size is X 5 one pound of these occupies about 750 ml. 

The columns are packed with Dixon [D3] rings made from 100-mesh phosphor bronze wire gauze. The colunms are operated at a mean pressure of approximately 0.5 atm, with a pressure drop of 130 Torr. Under these conditions, Dostrovsky and co-workers [D5] have found the 0- 0 separation factor to be 1.0064, and the height of a transfer unit in the larger columns to be about 2 cm. 

Kuhn, with his column, reached a concentration of 6 at. % of 0. Dostrovsky and his collaborators at the Weiszmann Institute in Israel [53], prepared of about 95% purity and of about 2%. The preliminary concentration from 0.2 to 1.6% of 0 was carried out in 10 columns connected in parallel (diam. 100 mm). The multistage cascade (diam. 80—100 mm) was fed at 800 ml/h and was operated with a takeoff ratio of 1.37 X10. The procedure is to be improved so as to produce a concentration of 99.8%. The highest concentration of is present at the centre of the cascade (<%i 10%). In these separations the Dixon packing, made of 100 mesh phosphor bronze wire gauze in the shape of a Raschig ring with an S-shaped bridge, proved its value... 

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