A Cost-Benefit Analysis of Black Liquor Gasification Combined Cycle Systems, 2003 Fall Technical Conference

Black liquor gasification (BLG) technologies are under active commercial development in the United States and Europe. BLG has been proposed as a future replacement for Tomlinson boilers to provide more efficient, safer, and environmentally-friendlier chemical and energy recovery. Also, some pulping process improvements are more readily implemented with BLG than with black liquor combustion. Because of potential efficiency and process benefits, BLG is viewed as an important technology for enhancing the competitiveness of the pulp and paper industry.

Much of the focus on BLG development has been on the coupling of chemical recovery with electricity production via gas turbine combined cycle technology (BLGCC). A better understanding of the economics and potential regional and national benefits of BLGCC could help catalyze commercialization of these systems. To that end, this paper summarizes the main results of a detailed study sponsored by the US Department of Energy, the pulp & paper industry and two electric utilities to assess the costs and benefits of BLGCC technology at the mill, Southeast US regional, and US national level [0]. The status of leading black liquor gasification technologies is summarized. Detailed mass and energy balances and capital cost estimates are presented for different BLGCC configurations and compared to state-of-the-art and advanced Tomlinson-based recovery systems. These are used for mill-level financial comparisons and to assess regional and national environmental benefits and energy savings potential.