CLAUS HYDROCARBON DESTRUCTION VIA STAGED SOLVENT REGENERATION

摘要

A solvent for absorbing H2S and CO2 is regenerated using two regenerators. Rich solvent is fed to a first regenerator producing a first acid gas stream from the top, and a partially regenerated solvent from the bottom. The partially regenerated solvent is fed to a second regenerator producing an overhead vapor stream from the top and a lean solvent stream from the bottom. A portion of the second regenerator overhead vapor stream may be cascaded to the first regenerator to contact rich solvent. The first acid gas stream and the remaining second regenerator overhead vapor stream are respectively fed to the first and second reaction zones of a two-stage Claus reaction furnace. Substantially all volatile organic contaminants are stripped in the first regenerator, and thus favorably destroyed in the first reaction furnace zone by virtue of higher local combustion temperatures and closer approach to oxidizing conditions.

主权项

1. A method for regenerating a rich solvent stream comprising solvent, H2S, CO2, and an amount of at least one volatile contaminant by using a carrier vapor to remove at least a portion of each of the H2S, the CO2, and the at least one volatile contaminant, thereby producing a lean solvent stream, wherein the H2S, CO2, and the at least one contaminant removed are to be fed to a Claus sulfur recovery unit of the type including a two-zone reaction furnace comprising first and second reaction zones, the method comprising:
feeding the rich solvent stream to a regenerator to produce the lean solvent stream from a lower section of the regenerator, an overhead vapor stream from an upper section of the regenerator, and a middle vapor stream from a middle section of the regenerator, wherein the overhead vapor stream comprises carrier vapor, H2S, CO2, and volatile contaminant and the middle vapor stream comprises carrier vapor, H2S, and CO2; cooling the overhead vapor stream to condense substantially all of the carrier vapor in the overhead vapor stream, thereby producing an overhead condensate stream and a first acid gas stream comprising H2S, CO2, and substantially all of the amount of the at least one volatile contaminant removed from the rich solvent stream; feeding the first acid gas stream to the first reaction zone of the two-zone reaction furnace; cooling the middle vapor stream to condense substantially all of the carrier vapor in the middle vapor stream, thereby producing a middle condensate stream and a second acid gas stream comprising H2S and CO2; feeding the second acid gas stream to the second zone of the two-zone reaction furnace; vaporizing a portion of a liquid stream from the lower section of the regenerator to produce a carrier vapor stream; and feeding the carrier vapor stream to the regenerator.