A model of a well-mixed fluidized-bed dryer within a process flowsheeiing package (SPEEDUP(tm)) has been developed and applied to a parameter sensitivity study, a steady-state controllability analysis and an optimization study. This approach is more general and would be more easily applied to a complex flowsheet than one which relied on stand-alone dryer modelling packages. The simulation has shown that industrial data may be fitted to the mode outputs with sensible values of unknown parameters. For this case study, the parameter sensitivity study has found that the heat loss from the dryer and the critical moisture content of the material have the greatest impact on the dryer operation at the current operating point. An optimization study has demonstrated the dominant effect of the heat loss from the dryer on the current operating cost and the current operating conditions, and substantial cost savings (around 50% ) could be achieved with a well-insulated and airtight dryer, for the specific case studied here.