Abstract: Turkey has abundant lignite reserves, but due to its low calorific value, combustion in circulating fluidized bed boilers is a more appropriate way to utilize it. The gas-solid flow state and combustion characteristics in the circulating fluidized bed boiler furnace are complex, and the flow characteristics as well as the combustion process will directly affect the boiler efficiency. In order to study the effect of operating parameters on the combustion characteristics of lignite coal in Turkey, a multiphase plasma lattice modeling method based on computational particle hydrodynamics (MP-PIC method) is used. The MP-PIC method is based on the Eulerian-Lagrangian model, in which the gas phase is processed using the Eulerian method, and the gas phase is solved using the Naiver-Stokes equations to solve the calculations, and the turbulence treatment utilizes the LES large eddy solution method to solve the turbulence structure more accurately, which can handle complex fluid phases. The particle phase is solved by the Lagrangian method, which can track the state of the particles and the change of the position, velocity and other parameters of the simulated particles over time. The Eulerian-Lagrangian model takes into account the interactions between the particle phase as well as the fluid phase, which can simulate the complex multiphase flow system and the particle movement law more accurately. A full-scale mathematical model based on the MP-PIC method was developed for a 130 t/h circulating fluidized bed boiler burning Turkish lignite to simulate the combustion characteristics in the furnace. In order to determine the appropriate number of grids, by monitoring the temperature distribution in the height direction of the furnace, the number of 500000 grids was selected for the continuation of the simulation considering the accuracy of the simulation results and the speed of calculation. The simulated values of the gas components at the outlet of the separator are in good agreement with the experimental values, indicating that the simulation results are valid for the prediction of this circulating fluidized bed boiler. The temperature distributions in the furnace, NO, CO, O₂ concentration distributions and NO emissions at the outlet of the cyclone separator were obtained from the simulation when the boiler burns the design fuel and the calibration fuel with different primary and secondary air ratios. The results show that there is no significant difference in the temperature distribution between the design fuel and the calibration fuel, the difference is not more than 50 K, and the temperature distribution in the furnace is uniform, and the flame filling degree is good. The ratio of primary and secondary air has little effect on the temperature in the upper and middle parts of the furnace, and the temperature in the dense zone decreases with the increase of the ratio of primary air. The primary and secondary air ratios had a significant effect on NO emission, and the best distribution of CO concentration and the lowest NO emission in the furnace were obtained when the primary and secondary air ratio was 55∶45. The results of the study can provide a reference for the design and operation of circulating fluidized bed boilers burning Turkish lignite.