Production of Liquid Methanol From Foul Condensate Stripping Systems, 1998 Environmental Conference Proceedings

James P. Witkowski

Union Camp Corporation

Norbert Eckert

Kvaerner Chemetics Inc.

John M. Wright

Kvaerner Chemetics Inc.

The stripping of foul condensates for methanol removal is now common in the pulping industry. Typically in these systems, a gaseous stream consisting of a mixture of 50 wt% methanol, total reduced sulfur (TRS) compounds, and water vapor is produced and then burned in a kiln, boiler or separate incinerator. Separate incinerators typically require use of a support fossil fuel. An enhancement to this approach is to further rectify the gaseous stream, generating a liquid product of a higher methanol concentration and heating value. The liquid product can then be used as the support fuel in a stand alone incinerator, eliminating the need for fossil fuels. Storage of a liquid product is also possible which offers the advantage of allowing stripping systems to continue to operate for a period without an available burning point. This is of particular benefit for stripping systems integrated to black liquor evaporator trains.

This paper will describe a liquid methanol rectification system installed and operated at the Union Camp Corporation mill at Eastover, South Carolina since 1991. Design features, operating experience and advantages of the system will be discussed.