Resource Efficiency as an environmental performance metric for industry: Exergetic analysis of a clinker manufacturing plant

Abstract

Control-data exergy-based Resource Efficiency (RE) analysis is applied to investigate resource use and efficiency improvements in the cement industry to understand what insights can be gained into the efficiency of clinker manufacturing and possible decarbonisation options when having full access to material and energy flows from the manufacturing plant control system. Mapping of the resources in and out of the clinker manufacturing section showed that total resource input is dominated by the flow of fuels, with the clinker burning section constituting the most energy and emissions-intensive part of the process. The plant is found to have an annual mean RE of 47.8% in compound operation, and 38.3% in direct operation. Three improvement options are identified: recycling of dust, reduction of heat transfer losses across the kiln, and optimisation of the plant's continuous operation. Heat losses reduction was found to have the largest improvement potential in terms of RE and CO2 emissions reduction. Despite providing a detailed representation of the real-time operation capable of identifying potential improvement interventions, the use of control-data is found to be highly intensive and time-consuming. In the future, it would be interesting to investigate whether the same level of insights into the efficiency and potential for decarbonisation of clinker manufacturing could be gained using less data.