Abstract:

Selective hydrogenation unit converts C₄ alkynes into high-value butadiene, which improves the economic efficiency of the unit while treating the dangerous alkynes. However, the return of hydrogenated C₄ alkynes to butadiene extraction unit may increase the load of the butadiene extraction unit, especially the load of the first extraction column. In this paper, the influence of newly installed C₄ alkyne selective hydrogenation unit on the load of extraction columns in butadiene extraction unit are analyzed. The results show that the hydrogenated C₄ mainly consists of C₄ monoolefins and alkanes, and the content of diolefin and C₄ alkyne is low, leading to different trends in the increase of gas load and liquid load in the first extraction column. The gas load in the rectification section of the first extraction column increases significantly, especially in the 41^st to 47^th trays above the C₄ feed tray near the flooding line, while the increase in liquid load is limited. The newly installed C₄ alkyne selective hydrogenation unit has a negligible effect on the load of the second extraction column.

Key words: extraction column')">

extraction column, C₄ alkyne, hydrogenation, 1,3-butadiene