Abstract: The invention is a process for removing H.sub.2 S, CO.sub.2 and mercaptans from a gas stream by liquid absorption using an absorbent wherein the mercaptans are absorbed at a high pressure and low temperature in a secondary absorption zone and separated from the absorbent by reduction of pressure after heating. The absorbent after reduction of pressure can be recycled to the absorpiton zone. The H.sub.2 S and CO.sub.2 are absorbed at a higher temperature than the mercaptans and are stripped from the absorbent in a regeneration zone after a reduction in pressure. The absorption zone requires two separate zones where the gas being treated passes from the high temeprature absorption zone to the low temperature zone where the mercaptans are removed.

Abstract: The present invention relates to a process for regenerating an absorbent solution, for example an aqueous solution of an alkanolamine, containing acid compounds such as CO.sub.2 and/or H.sub.2 S, in which said compounds are released by heating and/or stripped away. The regenerated absorbent solution, drawn off from the regeneration zone, is subject to a plurality of successive expansions with formation of a vapor in the course of each expansion, and the vapor thus formed is gradually compressed to form a compressed vapor, which is introduced into the regeneration zone. Such a process of regeneration with expansion of the regenerated solution is used in the regenerative processes for scrubbing gases containing acid compounds and renders possible an appreciable overall saving of energy.

Abstract: The invention concerns a process for the purification of residual industrial gases containing a small quantity of H.sub.2 S, SO.sub.2, CS.sub.2, COS, or possibly sulfur vapor, as well as large amounts of H.sub.2 O, CO.sub.2 and N.sub.2 in which the residual gases are first subjected to a catalytic reduction in which all the sulfur compounds are transformed into H.sub.2 S, and thereafter washed by an aqueous amine solution before being burnt and discarded into the atmosphere, while the aqueous amine solution is regenerated by heating and the gases given off, comprising H.sub.2 S and CO.sub.2, are returned to the sulfur manufacturing plant.The process is characterized in that the temperature of the gas to be treated is permanently maintained at a level higher than the dew-point of the water contained in the gases at all points of the process, thereby insuring that substantially all H.sub.2 O contained in the residual gases is discarded into the atmosphere.

Abstract: The invention concerns a process for the purification of residual industrial gases containing a small quantity of H.sub.2 S, SO.sub.2, CS.sub.2 COS, or possibly sulfur vapor, as well as large amounts of H.sub.2 O, CO.sub.2 and N.sub.2 in which the residual gases are first subjected to a catalytic reduction in which all the sulfur compounds are transformed into H.sub.2 S, and thereafter washed by an aqueous amine solution before being burnt and discarded into the atmosphere, while the aqueous amine solution is regenerated by heating and the gases given off, comprising H.sub.2 S and CO.sub.2, are returned to the sulfur manufacturing plant.The process is characterized in that the temperature of the gas to be treated is permanently maintained at a level higher than the dew-point of the water contained in the gases at all points of the process, thereby insuring that substantially all H.sub.2 O contained in the residual gases is discarded into the atmosphere.