INCREASING THE RATE OF GEOTHERMAL WELLS «GEOHYDROLIFT»

• Дата: 2022
• Автор: Morozov, Y.
• Формат: Стаття
• Мова: Українська
• Опубліковано: Institute of Renewable Energy National Academy of Sciences of Ukraine 2022
• Теми: geothermal well; thermal water; well flow rate; geohydrolift.
• Онлайн доступ: https://ve.org.ua/index.php/journal/article/view/365
• Назва журналу: Vidnovluvana energetika

One of the main indicators of the system for extracting geothermal energy sources from underground permeable layers is the production rate of geothermal wells, which determines the thermal power and thresholds with discharge pressure and the economic efficiency of geothermal technologies. The following methods of increasing the flow rate of geothermal wells are known: the use of submersible pumps, gas lift, air lift, thermal lift. A new method is proposed for increasing the flow rate of geothermal wells, which consists in pumping a liquid undissolved in water with a specific gravity less than the specific gravity of thermal water into the well through a dip tube. Let's call this method "thermohydrolift" or "hydrolift", that is, the rise of thermal water in a hydraulically connected system. The diagram of the geohydrolift is shown in fig. 1. The scheme includes a pump for pumping light liquid 1, a dip tube for supplying light liquid to well 2, well 3, an underground permeable layer 4 and a sump for a mixture of thermal water and light liquid 5. The action of a thermal lift, as well as a gas lift, airlift lowering the action of the weight of the barrel water in the well. The developed method for calculating the efficiency of using a hydrolift to increase the flow rate of a geothermal well involves considering a hydrolift as two hydraulically connected hydraulic systems. The first hydraulic system contains a permeable formation characterized by initial formation pressure Рst, dynamic formation pressure Рdin, productivity factor xp. The second hydraulic connected system contains: a pump, a dip tube for pumping a light liquid, annular between the pipe space, where the mixture of thermal water and working fluid moves, and a sump. An equation is obtained that determines the necessary pressure required for the injection of a light (working) fluid. The conditions under which the use of a hydrolift provides energy advantages over the use of a submersible pump are also substantiated.