Toward predicting the char bed shape in kraft recovery boilers

The authors have developed a model for describing the time-dependent change in char bed shape in kraft recovery boilers, and have implemented this model into a computational fluid dynamics (CFD) environment. The model was tested by simulating a 3150 tons dry solids/day kraft recovery boiler,, and was found to be capable of describing the change in bed shape resulting from calculated carbon accumulation. The model simulated the behaviour of the actual char bed relatively well. The current model offers a structure for further development toward a char bed model with better shape-predicting capability.