In order to recover efficiently the rich heat released from 1450□ blast furnace slag in the fluidized bed, we find the best control parameters by seeking the relationship among the control parameters, and their influence on heat transfer rate between gas and slag. This paper focus on CFD simulation of the fluidized bed heat transfer process. It adopts Eurelian-Eurelian approach, establishes the gas-solid phase governing equations to simulate nine kinds of operating conditions of dense gas-solid flow in a specific structured fluidized bed. The results show that the optimum control parameters are: the gas injected velocity 3m/s, the slag injected velocity 0.25 m/s, thus we achieve the gas-outlet heat transfer rate about 1200kW under the best operating condition. These findings provide reference for the structure design of the fluidized bed using for blast furnace slag waste heat recovery and are of great importance to guide the experimental study.