Coal-fired power generation brings about severe environmental impacts, such as air emissions, water pollution, and solid wastes. An exergy-based (exergetic, exergoeconomic, and exergoenvironmental) study of a coal-fired CHP system with waste heat recovery has been conducted. Firstly, waste heat profile is plotted with the extracted data to evaluate the recovery potential and feasibility. Models of rolling cylinder ash cooler (RAC) and absorption heat pump (AHP) are developed and integrated in the CHP system. Then, an analysis method that combines thermodynamic with economic analysis and life cycle assessment is proposed for thermal-economic-environmental considerations. Finally, the method is applied in three cases, named base case (without heat recovery), R1 case (applying RAC and AHP), and R2 case (applying RAC, AHP, and a new steam turbine). The results show that the overall efficiency increases from 32.94% (base) to 34.14% (R1) and 34.89% (R2). Solid waste and global warming are dominant impacts caused by coal burning. The unit cost and environmental impact of hot water have a sharp decrease (28.3% and 29.1%, respectively) in R2 case, which shows a better economic and environmental performance. (C) 2018 Elsevier Ltd. All rights reserved.
1.Northeastern Univ, State Environm Protect Key Lab Ecoind, Shenyang 110819, Liaoning, Peoples R China 2.Liaoning Acad Safety Sci, Energy Saving Ctr Boilers, Shenyang 110004, Liaoning, Peoples R China 3.Guodian Sci & Technol Res Inst, Nanjing 210046, Jiangsu, Peoples R China
Recommended Citation:
Zhang, Qi,Gao, Jintong,Wang, Yujie,et al. Exergy-based analysis combined with LCA for waste heat recovery in coal-fired CHP plants[J]. ENERGY,2019-01-01,169:247-262