Paper Pulping


Sandia researchers are currently working on several projects associated with the formation and deposition of entrained particles in recovery boilers. Recovery boilers are an essential part of the kraft pulping process that is used to make most of the world's paper. The energy efficiency and the availability of these boilers suffer when particulate matter is deposited on the steam tubes in the upper portion of the boiler. Chris Shaddix, using laser diagnostic and advanced sampling techniques, leads the effort to understand the details of particle formation and deposition. Fly ash deposition is particularly severe in these boilers because the large concentrations of sodium and sulfur in the fuel result in the formation of a large amount of sodium sulfate and sodium carbonate particles in the upper furnace. When these particles deposit on the steam tubes, boiler efficiency goes down.

Partners on these projects include:

McDermott Technology, Inc.
The Institute of Paper Science and Technology
The University of Toronto Pulp and Paper Centre
Process Metrix Corporation
Weyerhaeuser Company
International Paper
Georgia-Pacific Corporation

Sandia's Larry Baxter conducted laboratory deposit studies before leaving for a faculty position at Brigham Young University, where he continues to contribute to this work.