Research On Water Footprint Quantification And Water Resource Shortage Of The Thermal Power Industry

Water provides vital services for human health,livelihoods and well-being,while contributing to the sustainability of ecosystems.The increasing population and rapid urbanization and industrialization have resulted in the increasing demand for water resources.In addition,the water environment pollution caused by the irrational development and utilization of water resources has been worsening year by year.At the same time,water resource is a limited and irreplaceable resource.Therefore,from the macro point of view,the increasingly tense contradiction between supply and demand of water resources has been involved in the stable development of economic society and even the security of a country and a nation.Water resources crisis is one of the most serious practical problems facing human beings in the 21st century.Due to the lack of water resources,serious pollution and unreasonable utilization,water resources tension has become an important factor restricting the world economic and social development,and China's water resources are extremely scarce.China's water resources are faced with serious water pollution,over-exploitation of water resources and serious water waste.There are two main methods to solve the problem of water resource shortage.One is to realize the increase of income,decrease of expenditure and redistribution of water resources by means of water resource allocation policy planning,water diversion for water conservancy projects,seawater desalination,sewage reuse and improvement of water use efficiency from the perspective of real water resources.The other is to realize virtual water dispatching through commodity trade.The study shows that increasing the supply of solid water,optimizing the distribution and saving the use of water can not completely solve the water problem in the water-scarce areas,but also need to solve it from the perspective of virtual water.The water footprint quantization is the starting point for the related research of virtual water.Virtual water strategy is the key to building water-saving society in Zhangye city and quantification of water footprint is of great significance for the virtual water strategy.Traditional water footprint measurement methods mainly focus on agricultural and pastoral products,and the quantitative research on the water footprint of non-agricultural products is insufficient.In particular,the research on the particularity of blue water and gray water of non-agricultural products needs to be strengthened.In this paper,a hybrid life cycle assessment model and a universal grey water model are introduced to quantitatively study the water footprint of industrial products in Zhangye,a typical industry in Zhangye city,Heihe river basin,which is arid inland river basin.In this paper,the blue water footprint and gray water footprint in industrial products are distinguished from the direct water footprint and the indirect water footprint.Based on the water footprint of Zhangye city,the water resource shortage in Zhangye city is studied.Based on the establishment of the hybrid LCA model and the universal grey water footprint model,the water footprint of the Zhangye city's thermal power generation industry is 16.73m³·GJ^-1(equivalent to 0.06m³·kwh^-1).The direct water footprint was 16.35m³·GJ^-1,accounting for 97.8%.The indirect water footprint was0.372m³·GJ^-1,accounting for 2.2%,among which the local water footprint accounted for 81%and the external water footprint was 19%.The blue water footprint was mainly derived from 89.6%,and the grey water footprint was mainly derived from 10.4%.The blue water footprint was 9 times of the grey water footprint.The average I_blue index of water shortage in Zhangye city is 4.11,which is much higher than the threshold of severe water shortage 2 and there is a water shortage problem.In terms of water quality and water scarcity I_grey,the average is 0.48.The specific conclusions are as follows:?1?The direct water footprint is still the water-saving focus in Zhangye city's thermal power generation industry.The process of thermal power generation and wastewater discharge is the most important water footprint consumption in Zhangye city."Invisible"indirect water footprint also accounts for a certain proportion in the thermal power industry.Although the water footprint of coal mining and washing and selection process consumes a small proportion,it will also become the key point of water resource management and water-saving engineering,which is also the focus of this study.?2?The process of thermal power generation and sewage discharge consumes a large amount of water,and the large footprint of raw materials and equipment is the key.Analysis of different life cycle stages shows that the thermal power generation stage is the key water resource management cycle sewage for Zhangye city which has achieved the goal of reducing the grey water footprint.?3?The water footprint of Zhangye city's coal-fired power generation industry has decreased in recent years as the generation of environmentally friendly energy increases.Before 2011,Zhangye's power generation industry was dominated by thermal power generation and its water footprint was relatively large.After 2011,Zhangye has obvious advantages in hydropower and environmental protection energy generation and the power generation capacity of thermal power generation has decreased,so the water footprint of Zhangye's thermal power generation industry has decreased.?4?The thermal power generation industry in Zhangye is a serious water shortage industry.From 2008 to 2017,the average I_blue value of Zhangye's thermal power generation industry is 4.11,which is much higher than the threshold of severe water shortage 2,and there is water shortage problem,which belongs to the severe water shortage industry.In terms of I_grey,the average value is 0.48,which indicates that the water shortage in Zhangye has not reached the water shortage,but has reached half of the threshold.Zhangye needs to pay attention to the water shortage in the thermal power industry.We hope the water footprint quantification and water resource shortage research in Zhangye city will provide reference for virtual water strategy and water-saving project.