Performance comparison of cement production before and after implementing heat recovery power generation based on emergy analysis and economic evaluation: A case from China

HRPG (Heat recovery power generation) is widely adopted in the cement industry. However, the measure's impacts on the environmental and economic performance of this industry are not completely clear due to the extra resources inputs. To this end, this research implemented an emergy evaluation through considering emissions' impacts, to investigate impacts of HRPG on environmental performance of this industry. Meanwhile, a supplementary economic evaluation was done to explore changes of its economic performance before and after implementing HRPG. One cement enterprise with the two scenarios (Scenario 1 with HRPG vs. Scenario 2 without HRPG), as a case study, was investigated using the presented approach. It is found that (1) HRPG reduces total resources consumption by 1.13%, and raises share of renewable resources by 2.28%; (2) HRPG reduces dependence degree of this enterprise on imported resources and its wealth loss by 1.93% and 1.13% respectively; (3) HRPG enhances wastes recycling rate and energy efficiency by 329.44 times and 6.91% respectively; (4) HRPG enhances emergy yield rate by 0.89%, cuts environmental load rate by 1.77%, and improves environmental sustainability by 2.71%; (5) pollutant emissions' impacts reduce emergy yield rate by 9.48-9.56%, raise environmental rate by 0.02%, and weaken environmental sustainability by 9.50-9.59% (6) HRPG improves economic benefit of this enterprise by 22.24%, which roots in reduced electricity expense. Generally implementation of HRPG achieves energy-saving, emissions reduction and improvement of economic benefit, which well explains why this measure is widely adopted in cement industry. However, this measure is limited to improve environmental performance of this enterprise due to high dependence on nonrenewable resources, and it still has relatively lower energy efficiency than the updated one. Finally this study proposes some targeted suggestions to deal with these issues in the future. (c) 2021 Elsevier Ltd. All rights reserved.

Automated summary

Implementation of HRPG in the cement industry results in a reduction in total resources consumption and an increase in the share of renewable resources. HRPG also improves waste recycling rate, energy efficiency, and environmental sustainability.