Sustainability assessment of refining enterprises using a DEA-based model

As one of the basic industries supporting the national economy development and energy demand, the refining industry is expected to provide combustion energy, reduce pollution emission, and improve utilization efficiency. With more stringent requirement for environmental protection, refining enterprises have to insist on the sustainable development to achieve industrial optimization. Evaluation of the sustainability of enterprises can help them understand their situation more objectively and guide them to establish modes for sustainable development. In this study, the evaluation system is firstly built from perspectives of economic, ecological, and social sustainability, including six second-grade indexes and seventeen third-grade indexes, which can accurately reflect the entire sustainability contents of refining enterprises. Then, a DEA-based model is constructed, which selects seven input indexes (e.g., the asset-liability ratio and comprehensive energy consumption per unit of output) and nine output indexes (e.g., return on assets, asset turnover, and science and technology investment strength). The DEA-based model can not only objectively evaluate the sustainability level, but also find out the restriction factors for further optimization. Third, to demonstrate the validity of the model, 15 enterprises are selected for case studies, among which only four are identified as having strong sustainability. For the other 11 enterprises, projection analyses are implemented, and the DMU values of three enterprises characterized by low efficiency are adjusted to find out the restriction factors, which reflect the model's efficiency and its potentially wide application in the future. Finally, specific suggestions are proposed for the enhancement of sustainability of refining enterprises.