Patent ID: 6375806
Filing Date: 2002-04-23
Classification: B01D

Abstract:
A method of drying fuel gas containing water vapor and at least one pollutant comprising at least one member of the group consisting of volatile organic compounds, hydrogen sulfide and other gaseous pollutants, said method comprising:A. bringing said fuel gas into contact, in a gas/liquid contact vessel, with a liquid desiccant having an affinity for said water vapor and pollutant, thereby transferring water vapor and pollutant from said fuel gas into said desiccant; B. reconcentrating resultant rich desiccant containing water and pollutant by introducing said desiccant into a reconcentration system comprising a reboiler having a heating vessel, liquid and gas spaces in said heating vessel, a liquid outlet from said liquid space, and a column having a gas and/or vapor transmitting connection between said heating vessel gas space and said column and a vapor outlet for discharging gas and/or vapor from said column; C. maintaining a total pressure of at least about 25 PSIA in said heating vessel gas space while expelling pollutant from rich desiccant in said heating vessel and into said column; and D. discharging gaseous pollutant through said column vapor outlet, while preventing discharge of said gaseous pollutant from said reconcentration system into the atmosphere and recovering reconcentrated desiccant.