EXTRACTION EFFICIENCY HEAT OF ROCK MASS BY USING BOREHOLE

Abstract

Survey, parametric, oil and gas wells, which are derived from the operation may be used for extraction of earth warmth. The depth of these wells in Ukraine reaches 4000-5000 m and more. Geothermal gradient in the territory of the Dnieper-Donets depression on averages 2.7 °С/100 m, and in the area of Prykarpathia and Transcarpathia - 3,6-4,0 °С/100 m. Defined the following problem of unsteady heat transfer counter flow of heat carrieri in geothermal well. Calculated the specific heat flow from the mountain massif in the well using the solutions of the linear source (drain) in an endless mountain range and compared with available experimental data. Specific heat flow from the mountain massif to the coolant in the well varies 3 times at the end of 560 hours at a temperature drop 10 °С and further change in temperature over time is linear. The maximum thermal performance of the well depth of 5000 m at a geothermal gradient of 2.7 is 1.3 MW at the end of 40·10³ hours it drops to 0.65 MW.