Process for CO
View Patent ↗The present application relates to systems and processes for removal of gaseous contaminants from gas streams. In particular, the application relates to a process for removal of gaseous contaminants from a gas stream comprising contacting the gas stream with a wash solution to remove gaseous contaminants from the gas stream by absorption into the wash solution; and regenerating the used wash solution to remove gaseous contaminants from the used wash solution, to provide a regenerated wash solution and a gas comprising removed contaminants, wherein in a first regeneration stage the gas comprising removed contaminants is cooled to minimize loss of water vapor from the regeneration step.
1. A process for removal of gaseous contaminants from a gas stream, comprising
a) contacting a gas stream comprising gaseous contaminants with a wash solution, to remove gaseous contaminants from the gas stream by absorption into the wash solution;
b) passing used wash solution resulting from step a) to regeneration;
c) regenerating used wash solution by removal of gaseous contaminants from the wash solution, to provide a regenerated wash solution and a gas comprising removed contaminants;
d) passing the regenerated wash solution to reboiling;
e) reboiling the regenerated wash solution for further removal of gaseous contaminants from the wash solution, to provide a reboiled wash solution;
f) returning the reboiled wash solution to step a);
wherein during step f), the returned reboiler wash solution is subjected to heat-exchanging with the regenerated wash solution of step d) in a first heat-exchanging step, to heat the regenerated wash solution; and
heat-exchanging with used wash solution of step b) in a second heat-exchanging step, to heat the used wash solution; and further comprising
withdrawing a first portion of used wash solution resulting from the second heat-exchanging step; and
between the first and second heat-exchanging steps, subjecting the returned reboiler wash solution to heat-exchanging with the withdrawn portion of used wash solution in a third heat-exchanging step, to heat the used wash solution.
2. The process according to claim 1 , wherein in a first regeneration stage, the used wash solution cools the gas comprising removed contaminants to minimize water vapor loss.
3. The process according to claim 1 , further comprising
passing the first portion of used wash solution resulting from the third heat-exchanging step to reboiling; and
reboiling the portion of used wash solution for removal of gaseous contaminants from the used wash solution, to provide a reboiled wash solution.
4. The process according to claim 3 , wherein during the passage to reboiling, the first portion of used wash solution is combined with the regenerated wash solution of step d).
5. The process according to claim 1 , further comprising
passing the first portion of used wash solution resulting from the third heat-exchanging step to regeneration; and
regenerating the first portion of used wash solution for removal of gaseous contaminants from the used wash solution, to provide a regenerated wash solution.
6. The process of claim 5 , wherein the regeneration comprises a set of consecutive regeneration stages, and wherein the portion of used wash solution is subjected to regeneration in a regeneration stage downstream of the stage where the used wash solution of step c) is subjected to regeneration.
7. The process of claim 1 , wherein the gas stream is a natural gas stream or a flue gas stream.
8. The process of claim 1 , wherein the gaseous contaminants are acidic gases.
9. The process of claim 1 , wherein the wash solution is an amine-based wash solution.
10. The process of claim 1 , wherein the gaseous contaminants includes carbon dioxide.
11. The process of claim 1 , wherein regeneration comprises a set of consecutive regeneration stages.