Configurations and methods of high pressure acid gas removal in the production of ultra-low sulfur gas
First Claim
Patent Images
1. A method of treating a rich physical solvent, comprising:
- producing the rich solvent in an absorber, wherein the absorber receives a feed gas and produces a treated gas;
flashing the rich solvent in multiple successive stages from a first pressure to a second pressure to generate a hydrocarbon-containing flash gas and a flashed solvent, wherein flashing the rich solvent in the multiple successive stages occurs in a plurality of flash vessels, wherein the rich solvent passes through the multiple successive stages in series;
heating and further flashing the flashed solvent from the second pressure to a third pressure to generate a CO2-containing flash gas and a lean solvent; and
stripping a first portion of the lean solvent in a stripping column using a portion of the treated gas as a stripping gas to produce a stripping column overhead product and an ultra-lean solvent; and
feeding a second portion of the lean solvent and the ultra-lean solvent into the absorber at different positions.
1 Assignment
0 Petitions
Accused Products
Abstract
Acid gas is removed from a high pressure feed gas that contains significant quantities of CO2 and H2S. In especially preferred configurations and methods, feed gas is contacted in an absorber with a lean and an ultra-lean solvent that are formed by flashing rich solvent and stripping a portion of the lean solvent, respectively. Most preferably, the flash vapors and the stripping overhead vapors are recycled to the feed gas/absorber, and the treated feed gas has a CO2 concentration of less than 2 mol % and a H2S concentration of less than 10 ppmv, and more typically less than 4 ppmv.
-
Citations
20 Claims
-
1. A method of treating a rich physical solvent, comprising:
-
producing the rich solvent in an absorber, wherein the absorber receives a feed gas and produces a treated gas; flashing the rich solvent in multiple successive stages from a first pressure to a second pressure to generate a hydrocarbon-containing flash gas and a flashed solvent, wherein flashing the rich solvent in the multiple successive stages occurs in a plurality of flash vessels, wherein the rich solvent passes through the multiple successive stages in series; heating and further flashing the flashed solvent from the second pressure to a third pressure to generate a CO2-containing flash gas and a lean solvent; and stripping a first portion of the lean solvent in a stripping column using a portion of the treated gas as a stripping gas to produce a stripping column overhead product and an ultra-lean solvent; and feeding a second portion of the lean solvent and the ultra-lean solvent into the absorber at different positions. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10)
-
-
11. A method of treating a rich physical solvent, comprising:
-
flashing the rich solvent in multiple successive stages from a first pressure to a second pressure to generate a hydrocarbon-containing flash gas and a flashed solvent, wherein flashing the rich solvent in the multiple successive stages occurs in a plurality of flash vessels, wherein the rich solvent passes through the multiple successive stages in series; heating and further flashing the flashed solvent from the second pressure to a third pressure to generate a CO2-containing flash gas and a lean solvent; and stripping a portion of the lean solvent in a stripping column to produce a stripping column overhead product and an ultra-lean solvent; feeding the lean solvent and the ultra-lean solvent into an absorber at different positions, wherein feeding the lean solvent and the ultra-lean solvent into an absorber at different positions produces a treated gas; feeding a portion of the treated gas to the stripping column; expanding the portion of the treated gas prior to feeding the portion of the treated gas to the stripping column, wherein a refrigeration content from the expansion of the portion of the treated gas cools the ultra-lean physical solvent. - View Dependent Claims (12, 13, 14, 15, 16, 17, 18, 19, 20)
-
Specification