Optimization Of The Cascade Utilization System Of Middle And Deep Geothermal Energy

In China, almost middle and deep geothermal energy exist in the form of low-temperature geothermal fields. Especially in Shandong province, the characteristics of geothermal resource include wide distribution, large reserves and better mining condition. However, because of its development level was in spontaneous, dispersed and extensive at technical aspects, waste of geothermal resources is serious and low levels of comprehensive development and utilization. Geothermal tail water has discharged nearby ground more common. To bring a serious negative impact on the water environment.Based on the enhance heat transfer rate and water system optimization operation aspects, these paper introducing the theory of "entranspy dissipation" into geothermal heating technology. It has analyzed the entranspy analysis to plot the heat exchanger about the optimization strategy, identified the selection principle of main equipment on the entranspy; It has analyzed different forms of geothermal water system and its optimization criterion; It has proposed two more feasible execution policy. And the application of these research results to a geothermal heating Heze renovation project, the design and optimize the system transformation.Study on the geothermal heating system enhanced heat transfer efficiency. In the given conditions entranspy dissipation minimum optimization criterion. When a given heat exchanger hot and cold fluid outlet temperature, thermal fluid heat capacity smaller the difference, the smaller the entranspy dissipation of the plot, the faster the rate of heat transfer; when given the hot and cold fluid heat capacity, the heat fluid (fluid or cold) Importers greater the temperature difference, the smaller the entranspy dissipation of the plot, the faster the rate of heat transfer; when given the heat exchanger, the greater the fluid heat capacity, entranspy dissipation smaller plot, the faster the rate of heat transfer.Established optimization method geothermal water systems. Follow the "expand geothermal energy can be used to reduce the temperature difference and the exploitation of geothermal water" principle. Be achieved by controlling the water flow geothermal wells, recharge temperature control measures or control the low-temperature side heat exchanger outlet temperature and other measures. Projects and tested the feasibility of the method.Heze in Shandong region presented a geothermal heating renovation project plan. Field research visits, expand its heating capacity, reduce the amount of geothermal water exploitation and increase aspects of the system and its main heating equipment, heat capacity, optimized transformation. Proposed two optimization scheme:"increase the number of stages of cascade utilization and heat storage tank" and "increase the number of stages of cascade utilization and central heating peak shaving", depth optimization principles and strategies of practical applications in engineering, and gain a more comprehensive in-depth analysis of geothermal water conservation, improve energy efficiency of heating and geothermal energy utilization, thermal breakthrough time and economy, etc. To determine the program of "increase the number of stages of cascade utilization and heat storage tank". Based on the established use of geothermal gradient optimization technology for engineered results show that:the optimization method proposed is feasible and operability.