Study On The Design And Operation Of Water Reuse In A Thermoelectric Group

Water is important natural resource for our survival and development.China is a large country of water resource.However,due to the large population,the per capita water resource is very small.In recent years,with the growth of China's population and the rapid economic development,the problem of water shortage has become more serious.Water resources have increasingly become a strategic resource for countries around the world.Many developed countries have begun to develop second water sources in early time,such as desalination and reuse of reclaimed water,The reuse of reclaimed water has become an important way to alleviate the crisis of water resources.In China,water reuse has taken the first in in water deficient areas and developed areas.In recent years,along with the importance of ecological environment protection has been increasing,the policies and regulations becoming more and more improving and stern gradually,and also secretary Xi Jinping emphasized that “ Treating the ecological environment as if it were to treat life so that the motherland's land is green and beautiful.” Driven by policies,the price of industrial tap water has increased year by year,and industrial companies have been more restricted in the use of surface water and groundwater.Under such circumstance,the reuse of reclaimed water has become an important and economical strategy for solving problems.The term "Reclaimed Water" originated in Japan and refers to all reusable water except for the original water and sewage.Domestic sewage and industrial wastewater can be reused in various ways after reaching certain water quality standards after treatment,and generally not used as drinking water.Since the beginning of the 1920 s,the United States has taken the lead in starting the reuse of water.After nearly a century of development,the way of recycling water has been diversified,such as direct use in agricultural irrigation,industrial water,urban greening,landscape water,rivers and lakes supplement water and groundwater recharge,and even dry areas such as the Netherlands,parts of the United States,and southern Israel are directly used as drinking water.The water reuse technology has also been greatly developed.According to different application methods,there are biochemical,physical,and physical biochemical process.In recent years,with the rapid development of China's industry,water reuse technology has developed rapidly,and the " UF-RO method " is favored because of its good water quality,stable operation,and high automation.Domestic sewage and industrial waste water are used as reclaimed water sources,the components in the water are very complex and can easily cause pollution and damage to the plant,such as COD,BOD,ammonia nitrogen,phosphorus,SS,and various heavy metals and hydrocarbons in industrial wastewater may cause bacteria growth,accumulation of organic substances,clogging of filtration equipment,and calcium and magnesium scale on the surface of the filter membrane,resulting in a decrease in the rate of water production and a deterioration in the quality of the effluent water.Therefore,a successful reclaimed water project requires not only a rational process design,accurate equipment selection,but also various control of operating conditions and maintenance during operation.Wei Hai is located at the eastern end of the Shandong province and is one of the most water-shortage cities in the north.A thermoelectric group in Wei Hai takes the responsibility for the heating of more than 32 million square meters of residents of 310,000 households there.Annual production water consumption is more than 8 million tons.With the number of business users and residents continuous increasing,the average annual water consumption needs to increase by more than 1 million tons,It is a large water user in Wei Hai.Due to the shortage of fresh water resources in Wei Hai,the problem of shortage of water is becoming increasingly serious.The cost of the Yellow River water transfer is relatively high and the financial subsidies to the municipal government are under great pressure.Water saving,reclaimed water deeply reuse and seawater desalination are extremely urgent.Reclaimed water deeply reuse is an important measure to promote a conservation-minded city and benefit the people of Wei Hai,alleviate the tension between water resource shortage and the number increase in water consumption,reduce the water use pressure in Wei Hai,and set a new benchmark for Wei Hai's reclaimed water deeply reuse.Based on the above background,this article conducts a technical and economic analysis of the water reuse scheme,including the design of the process route,equipment selection,investment estimation,and operation cost analysis.It also provides guidance on the production of the water supply plant based on actual operational data analysis.After the project is put into production,8.76 million tons of recycled water can be produced per year,which is of great significance.