1985 Volume 11 Issue 6 Pages 708-714
A crude acetylene produced by partial combustion of natural gas and containing 1 % of heavy acetylene compounds such as methyl acetylene as impurities was purified by a large moving-bed adsorber for the purpose of vinyl acetate synthesis. Through adsorption by a moving bed of crushed active carbon, the impurities were reduced to as low as 0.1-0.3 %.
Experiments were performed with three adsorbers of different sizes (100, 320 and 1000 mm in diameter) to obtain data on mass transfer as well as to make clear the effect on designing and operating a moving-bed adsorber. Finally, an industrial plant 2.2 m in diameter, 17.5 m in height and having a 38 m3 bed volume was constructed.
Through experiments with equipment of different sizes, the following results were obtained. The moving velocity of the carbon particles showed a considerable distribution in the radial direction and the value of HETP became larger with increasing bed diameter.
In spite of these disadvantages, the operation of the industrial adsorber showed good performance, resulting in high-grade purification of the gas, low by-products formation and low deactivation rate of the catalyst in vinyl acetate synthesis.
