Combustion and Emission Characteristics of Multi-Source Biomass/Coal Gasification Fine Slag Composite Pelletized Fuels at High Heating Rates
Pelletizing technology is widely applied in biomass and coal fuel processing, offering advantages in transport, storage, and energy density. Coal gasification fine slag (CGFS), a carbon-rich coal-based solid waste, holds potential as a fuel. This study prepared centimeter-scale composite pellets by blending CGFS with various biomass types under 6 MPa at room temperature for 2 minutes. Combustion and emission characteristics were investigated using a self-developed flat-flame macro-thermogravimetric reactor simulating high heating rate conditions. Results showed that biomass type significantly influenced combustion due to chemical composition differences. Introducing biomass altered fuel particle composition, enhancing combustion rates of single-component fuels by 3–5 times during volatile combustion. Co-combustion reduced NOx and CO emissions by over 50% compared to pure CGFS. Higher biomass ratios accelerated volatile release and shortened burnout time but increased NO emissions due to higher volatile nitrogen content. Conversely, CO emissions decreased due to improved char combustion conditions. These findings provide critical experimental support for optimizing clean and efficient solid fuel production from CGFS and biomass.