提高水资源使用效率和污水处理效率是解决目前水资源短缺的重要途径。中国工业用水系统可分为生产用水子系统和污水处理子系统。本文考虑两个子系统之间的联系,并区分污染物在两个子系统中的弱处理和强处理特性,提出了一种基于DEA的两阶段评价模型。应用本文提出的新模型分析中国30个省级区域的工业用水系统的效率,结果表明:中国省级区域工业用水整体效率不高,且地域分布特征明显,东部、西部、中部效率依次递减;中国工业用水系统的非有效性主要源于污水处理效率的影响;工业用水系统效率与地区水资源禀赋存在一定的关系,水资源短缺的地区用水效率相对较高。文章所提出的方法兼顾生产用水子系统和污水处理子系统之间的相互影响,能够同时评价两个子系统效率和工业用水系统的整体效率,能有效发现系统中影响整体效率的关键环节,且可以应用于其他能源效率评价问题,具有明显的实际应用价值。
Water use performance and wastewater decontamination performance improvement is an effective way to alleviate water shortage.Industrial production system in China can be divided into production water use sub-system and wastewater decontamination sub-system.By considering the linkages between the two sub-systems and the disposability of pollutants in different sub-systems,a new two-stage network DEA model is proposed to evaluate the performance of china's industrial water use systems.The proposed model is applied to evaluate the performance of 30 regional industrial water use systems of China.The application results show that the overall efficiency of regional water use systems is relatively low in China and the inefficiency is largely driven by wastewater decontamination performance.There exist significant regional disparities in water use efficiencies of regions and areas.In particular,evident relationships between water use efficiency and water resource endowment,and a region may achieve a high efficiency score with relatively lower resource endowment,and vice versa.The proposed model can simultaneously evaluate the efficiencies of the whole industrial water use system and its two sub-systems,and it can identify the key factors that affect the performance of industrial water use systems.The proposed model can also be applied to evaluate regional energy efficiencies.All these show the great practical value of the proposed model.