Atmospheric pyrolysis and gasification of kraft black liquor solids (KBLS) in the presence of TiO2 was conducted in a pilot fluidized-bed system operated at 700-900 degrees C. The effects of temperature, air ratio, and TiO2 particle size on the product gas composition and yields were investigated. The major components of the product gases are carbon monoxide, carbon dioxide, hydrogen, methane, and ethylene. The residual organic and inorganic carbon (carbonate) of the bed solids was determined. The heating value of the product gas and its behavior with operating conditions was also determined. It was found that addition of TiO2 to the gasifier had little influence on the carbon gasification of KBLS. The results suggest that for practical KBLS gasification, the temperature should be as high as possible (but less than similar to 900 degrees C), and that the air ratio be controlled at a value of 0.3-0.4.