Continuous multistage degasification of liq. sulphur - by contact with hydrogen sulphide-lean carrier gas in a series of contact chambers

摘要

H2S-rich liq. S is degasified by (a) continuously supplying the S to the first stage of a contacting zone contg. >1 discrete contacting stage, the S occupying the lower part of the zone (b) continuously feeding an H2S-lean carrier gas into the upper part of the first stage such that gas and liq. S are sepd. by an interface, (c) continuously withdrawing H2S-lean liq. S from the lower part of a subsequent stage and (d) continuously withdrawing H2S-rich carrier gas from the upper part of a subsequent stage. The liq. S is maintained at 120-160 degrees C and is recirculated within >=1 stage at a rate of 1-100X the S feed rate. In a pref. process the liq. S feed contains 70-300wt. ppm H2S and the liq. S withdrawn contains 15 wt ppm H2S. Used esp. in a Claus process; in a pref. operation the S pit for storing the liq. S prod. comprises the contacting zone. Method is continuous and does not require a separate degasification vessel.