基于DEA模型的农村生活垃圾处理工程环境及经济效益评估

农村生活垃圾处理示范工程长期存在重建设轻后评估和管理的问题。利用DEA模型对21个广西农村生活垃圾处理示范工程案例开展绩效评估,并利用Kruskal-Wallis检验分析各示范工程综合技术效率的显著差异。结果表明:1)绩效好的示范工程中,其中有10个焚烧示范工程,2个热解示范工程,污染物产出指标对绩效评估结果有一定影响;2)焚烧、热解和生物发酵处理方式均适用于农村生活垃圾处理;3)绩效好的垃圾焚烧示范工程污染物控制上基本都采取了采用水沐法的控制工艺,绩效好的垃圾热解示范工程污染物控制上基本都采取了采用热解气化+二燃室+布袋除尘+活性炭吸附工艺;4)生活垃圾分散小型焚烧、热解工程项目吨处理垃圾一次性投资额建议分别控制在(15.92±11.98)万元(焚烧)、(35.00±7.07)(热解)万元范围;吨处理成本应控制在:焚烧为(26.08±15.33)元、热解为(57.5±10.61)元范围;占地面积应控制在焚烧(39.74±18.19)m~2/t、热解(7.33±2.31)m~2/t。绩效评估的结果可作为农村生活垃圾处理应用示范的主要依据,为广西乃至全国全面推广农村生活垃圾处理提供有益参考。

Environment and economy efficiency valuation for rural domestic solid waste treatment demonstration projects using DEA method

Abstract: During the next 10 years, national or local governments invest much capital to construct several rural solid waste treatment demonstration projects. However, the construction of rural domestic solid waste treatment demonstration projects overweighs its evaluation and management, which has been become the barrier that affects the achievement of the goal for the full coverage of rural solid waste harmless treatment. In this study, three index system scenarios were designed for the performance evaluation. The index system comprised input indices and out indices. The input indices include the occupied area, one-time investment, operation investment, etc., output indices include rural domestic solid waste treatment amount, emissions of air pollutants, water pollutants discharge, etc. In scenario 1, rural domestic solid waste treatment amount was designed as the sole output index for performance. In scenario 2, rural domestic solid waste treatment amount and air pollutant emission control were both considered in output index system. In scenario 3, rural domestic solid waste treatment amount, air pollutant emission control and water pollutant discharge control were all considered in output index system. Data envelopment analysis (DEA) method was used for performance evaluation for the 21 solid waste treatment demonstration projects in Guangxi of China. Afterwards, Mann-Whitney & Kruskal-Wallis test were applied to test the significant difference of comprehensive technical efficiency among incineration treatment, pyrolysis treatment and bio-fermentation treatment. Finally, the investment reasonable ranges of rural solid waste treatment were obtained. The results showed that: 1) 12 demonstration projects showed good performance, in which 10 projects using incineration technology, and 2 projects using pyrolysis technology. Additionally, pollutant output indicators have some impacts on the performance evaluation results. The results have some could provide a reference for the strategy adjustment of the specific demonstration projects. For the projects with low scale performance, it should be better if the total treatment scale and the occupied area were lower, or the operation efficiency was re-adjusted. 2) Incineration, pyrolysis and biological fermentation technology weer all suitable for rural domestic waste treatment. 3) Incineration demonstration projects with good performance had generally used water bathing control process for pollutant control. Pyrolysis demonstration projects with good performance had adopted the gasification, secondary chamber, activated carbon adsorption and bag filter system for pollutant control. 4) The recommended one-time investment control of domestic waste treatment using incineration, pyrolysis and biological technology should be among the range of (15.92±11.98)×104RMB, (35.00±7.07)×104RMB per ton, respectively. The recommended daily operation control of domestic waste treatment using incineration, pyrolysis and biological technology should be among the range of (26.08±15.33)×104RMB, (57.5±10.61) ×104RMB per ton, respectively. The recommended one-time land occupation control of domestic waste treatment using incineration, pyrolysis and biological technology should be among the range of (39.74±18.19)×104RMB, (7.33±2.31) ×104RMB per ton, respectively. The performance evaluation results can provide reference for screening feasible rural domestic solid waste treatment technologies and fully covering application in rural areas of China.