Process for recovery of alkanolamines used in amine sweetening processes

摘要

A process for recovering an alkanolamine from a used gas scrubbing stream wherein a dynamic reaction system is employed to maximize conversion of bis-urea compounds typically formed in the gas scrubbing operation into the alkanolamine and minimize the formation of amino ethers which irreversibly convert the alkanolamine. A method of removing waste products from the system by the use of a wiped film evaporator.

主权项

1. A process for recovering an alkanolamine from a wash stream used to remove acid gases from a gas stream, comprising:
introducing a fluid stream comprising water, a linear ether alkanolamine, and up to about 20 wt % carbamate precursor into a reaction zone maintained at a positive pressure and at a temperature of from about 250° F. to about 400° F.; circulating said fluid stream through said reaction zone at a rate to provide a residence time of from about 0.5 to about 1 hour of said fluid stream in said reaction zone to convert at least a portion of said carbamate precursor to said alkanolamine and carbon dioxide and reduce the formation of amine ethers; recovering a product stream from said reaction zone comprising water, carbon dioxide and alkanolamine; recycling a portion of said product stream to said fluid stream to at least partially control the residence time of said fluid stream in said reaction zone.