A new energy efficiency evaluation solution for ethylene cracking furnace based on integrated TOPSIS-DEA model

Ethylene-cracking furnace has the highest energy consumption of all the devices used in the ethylene industry. The accurate energy-efficiency evaluation of an ethylene-cracking furnace is therefore of great significance for energy saving and productivity gain in ethylene production. Traditionally, a data envelopment analysis (DEA) model has been used to evaluate the energy efficiency. However, ethylene-cracking furnace also involves a multi-index and multiworking-condition energy-efficiency evaluation problem that results from there being multiple material flows, multiple energy flows, and multiple production loads. Therefore, this paper proposes a new energy efficiency evaluation solution for an ethylene-cracking furnace that is based on the integrated technique for order preference by similarity to ideal solution (TOPSIS)-DEA model. First, from the perspective of material and energy flows, an energy-efficiency vector (EEV) is designed and integrated into the DEA model to meet the demand for multi-index evaluation. Second, to eliminate interference of changes in working condition on energy efficiency, double virtual energy-efficiency benchmarks (DVEEBs) are built using the relationship between EEV, operating conditions, and nonoperational factors, based on the established cracking model. Finally, the rearranged values of the EEV is solved by the TOPSIS method and then evaluated by the DEA model. The actual numerical results show that the proposed solution can support energy-efficiency evaluation of an ethylene-cracking furnace subject to the multiple indexes and multiple working conditions. Specifically, the interference of changes in the working condition on the evaluation results can be reduced greatly which ensures the accuracy and objectivity of the energy-efficiency evaluation results.