办公楼中水回用成本效益分析

中水回用系统节省淡水资源，缓解城市给排水压力，社会效益显著。但是在经济效益层面，中水回用系统存在争议。针对北京地区办公楼中水回用问题，采用动态投资回收期分析法，结合对未来水价、电价的走势和维保费的模拟，针对Matlab 软件计算结果，分析并讨论了中水系统在办公楼中的成本效益。结果表明，目前办公楼中水系统不具备经济投资效益；水价以及运行、维保费的增长率是影响中水回用系统经济效益的主要因素。但随着中水回用系统投入使用的推移，动态投资回收期在减少。到2021 年以后中水回用系统投入使用，开始具备经济投资效益。

Cost-benefit Analysis of Gray Water Recycling Utilized in Office Building

Gray water recycling system reserves water resource and relieves pressure of municipal water and wastewater which has great potential social benefit. However，gray water recycling system rises controversy in terms of economic benefit. Focusing on gray water recycling system in a research office building located in Beijing，cost-benefit analysis of gray water recycling in the research office building is analyzed and discussed in terms of using dynamic investment pay-back period method solved by Matlab software which combines the simulation of future running water prices，electricity prices and operating & maintenance fees. At present， economic investment of gray water recycling system is turned out to be in vain. Running water prices and increasing rate of operating & maintenance fees are the key factors which have a serious influence on economic benefit of gray water recycling system. With delay of implementation of gray water recycling system，dynamic investment pay-back period is decreasing. Economic investment efficiency of gray water recycling system emerges when the system implements after 2021.