To reduce heat loss from the shell of a rotary kiln is of great significant for saving energy consumption in cement production. In this paper, a waste heat power generation system is proposed which contains an evaporator, a superheater, a condenser, a turbine and a heat recovery system with nine heat recovery exchangers. Then, integration of thermodynamic and thermal resistance analyses yields mathematic relations between the system requirements and the design parameters, i.e. the thermal conductance and mass flow rates, which form the constraint equation group of a global optimization model. With the aid of the Lagrange multiplier method, the optimized structrual and operational parameters are obtained. The results illustrate that the optimized thermal conductance of the heat recovery system is reduced by 10% compared with the value before optimization. As the mass flow rate of the system increases, the evaporation temperature decreases. The total thermal conductance of the whole system is increased as the cooling water temperature increases and the work output of the turbine increases.