Performance evaluation of a novel design for the waste heat recovery of a cement plant incorporating a coal-fired power plant

Abstract

A novel waste heat recovery system (WHRS) for cement plants is proposed in this study. The new WHRS is integrated with the heat regeneration process of a coal-fired power plant. The thermal energy recovered from the exhaust gases of a cement plant is poured into the steam cycle of the coal-fired power plant. Consequently, the performance of the waste heat utilization process can be significantly improved. The hybrid design was thermodynamically and economically assessed based on a typical cement plant and a coal-fired power plant. The results indicated that while the thermal energy recovered from the exhaust gases of the cement plant is constant, the new WHRS can produce 6.75 MW more net power than the conventional one. Meanwhile, the power generation efficiency and net thermal efficiency of the WHRS are increased by 18.11% and 8.11%, respectively. The net present value of the WHRS can be promoted by 230.42% by implementing hybridization. Furthermore, energy and exergy analyses were undertaken to investigate the root cause of performance enhancement due to the proposal. The results confirmed that the novel design is advantageous from the perspectives of both thermodynamics and economics.