Preliminary economics of black liquor gasifier/gas turbine cogeneration atpulp and paper mills

Black liquor, the lignin-rich byproduct of kraft pulp production, is burned in boiler/steam turbine cogeneration systems at pulp mills today to provid e heat and power for onsite use. Black liquor gasification technologies und er development would enable this fuel to be used in gas turbines. This pape r reports preliminary economics of 100-MWe scale integrated black-liquor ga sifier/combined cycles using alternative commercially proposed gasifier des igns. The economics are based on detailed full-load performance modeling an d on capital, operating and maintenance costs developed in collaboration wi th engineers at Bechtel Corporation and Stone & Webster Engineering. Compar isons with conventional boiler/steam turbine systems are included.