DEVELOPMENT OF THE TECHNIQUE OF OPERATION OF GEOTHERMAL SYSTEMS WHEN EXTRACTING ASSOCIATED GASES

Objectives. The aim of the study is to develop a method of operating geothermal energy systems in the mode without scaling when disposing of flammable gases with geothermal water in wells with a low gas factor.

Method. The studies were conducted on the basis of analyzing the content of associated flammable gases in the underground thermal mineral waters of the North Caucasus and Ciscaucasian deposits and assessing the possibility of their utilization and use for heating and hot water supply. In this case, the laws of dissolution and desorption of methane and carbon dioxide from groundwater solutions with the content of scale-forming components, in particular, calcium carbonate, are used.

Result. On the basis of the conducted research, it was found that the operation of g eothermal systems in the power industry should be carried out after preliminary withdrawal of the maximum possible amount of associated flammable gases from a water solution, while maintaining the content of carbon dioxide in water at a level above the equilibrium value. The scheme of the effective operation of thermal distribution stations with the prevention of carbonate deposits in them is given by using the products of associated gas combustion in the waste water when it is pumped back into the aquifer.

Conclusion. As a result of the research conducted, a method of operating geothermal energy systems in a non-salt-scale mode has been developed for utilization of combustible gases associated with geothermal water. It has been established that in order to accelerate the dissolution of carbon dioxide in water to stabilize it before entering heat-exchange equipment, it is advisable to increase the partial pressure of carbon dioxide to values exceeding by an order of magnitude the equilibrium at a given temperature. At the same time, before pumping waste water back into the aquifer, excess carbon dioxide is removed from the water.

1. Akulinchev B.P., Panchenko A.S., Pugacheva M.F. Vodorastvorennyye gazy Predkavkaz'ya i problemy ikh ispol'zovaniya v narodnom khozyaystve //Resursy netraditsionnogo gazovogo syr'ya i problemy yego osvoyeniya. Leningrad, 1990 g. S. 138-144. [Akulinchev B.P., Panchenko A.S., Pugacheva M.F. Water-dissolved gases of Ciscaucasia and the problems of their use in the national economy // Resources of unconventional gas raw materials and problems of its development. Leningrad, 1990, pp. 138-144. (in Russ)]

2. John W. Lund ,Tonya L. Boyd. Direct utilization of geothermal energy 2015 worldwide review//Geothermics, March 2016.- Volume 60. - Pages 66-93

3. Holm, Alison. Geothermal Energy: International Market Update:Geothermal Energy Association [Elektronnyy resurs]/Alison Holm, Leslie Blodgett, Dan Jennejohn, Karl Gawell. May 2010). pp.7. rezhim dostupa: http://www.geoenergy.org/pdf/reports/gea_international_market_report_final_may_2010.pdf.

4. Kurbanov, M.K. Geotermal'nyye i gidrotermal'nyye resursy Vostochnogo Kavkaza i Predkavkaz'ya / M.K. Kurbanov // M.: Nauka, MAIK «Nauka/Interperiodika», 2001. – 260 s. [Kurbanov, M.K. Geothermal and hydrothermal resources of the Eastern Caucasus and Ciscaucasia / M.K. Kurbanov // M .: Science, MAIK "Science / Interperiodica", 2001. - 260 p. (in Russ)]

5. Sultanov YU.I., Zav'yalov S.F., Badavov G.B. Vozmozhnosti ispol'zovaniya goryuchikh gazov na termovodozabore Makhachkala I –Ternair /Yezhegodnik: Geotermiya. M.: Nauka, 1991.- S. 47 – 53. [Sultanov, Yu.I., Zavyalov, SF, Badavov, G. B. Possibilities of using combustible gases at thermal water intake Makhachkala I –Ternair / Yearbook: Geothermy. M .: Nauka, 1991.- p. 47-53. (in Russ)]

6. SanjaMrazovac, Djordje Basic. Methane-rich geothermal waters in the Pannonian Basin of Vojvodina (northern Serbia) //Geothermics, September 2009.- Volume 38.-Issue 3.- Pages 303-312

7. Ganjdanesh, Reza; Hosseini, SeyyedAbolfazl. Potential assessment of methane and heat production from geopressured-geothermal aquifers//Geothermal Energy; Heidelberg 4.1 (Nov 2016): 1-25.

8. Akhmedov G.YA. Zashchita geotermal'nykh sistem vodopodgotovki ot karbonatnykh otlozheniy //Energosberezheniye i vodopodgotovka.- 2010.- № 6.- S. 18-21. [Akhmedov G.Ya. Protection of geothermal water treatment systems from carbonate sediments // Energy Saving and Water Treatment. - 2010.- № 6.- P. 18-21. (in Russ)]

9. Abdullayev A.N. Predotvrashcheniye obrazovaniya otlozheniy tverdoy fazy SaSO3 v skvazhine/Yezhegodnik: Geotermiya. M.: Nauka, 1991.- S. 81 – 84. [Abdullaev A.N. Prevention of formation of sediments of the solid phase of CaCO3 in the well / Yearbook: Geothermy. M .: Science, 1991.- p. 81 - 84. (in Russ)]

10. Pat. US 9121259 B2, C10L3/06, C07C1/00, B01J19/00, E21B43/295, C07C7/10. Storing carbon dioxide a nd producing methane and geothermal energy from deep saline aquifers /Steven L. Bryant, Gary A. Pope. Pub. 01.09.2015 (rezhim dostupa: https: //www.google.ch/patents/US9121259)

11. Oliker, I.I. Termicheskaya deaeratsiya vody na teplovykh elektrostantsiyakh /I.I. Oliker, V.A. Permyakov. – L.: Energiya, 1971. – 185. [Oliker, I.I. Thermal deaeration of water in thermal power plants / I.I. Oliker, V.A. Permyakov. - L .: Energy, 1971. - 185 p. (in Russ)]

12. Permyakov V.A. Issledovaniye primeneniya parovogo barbotazha v termicheskikh deaeratorakh: avtoref. dis. … kand. tekhn. nauk /Permyakov V.A. – Moskva: MEI, 1954. – 23 s. [ (Permyakov, V.A. Investigation of the use of steam bubbling in thermal deaerators: author. dis. ... Cand. tech. Sciences / Permyakov VA - Moscow: MEI, 1954. - 23 p.(in Russ)]

13. Akhmedov G.YA. Stabilizatsionnaya obrabotka geotermal'nykh vod //Vodosnabzheniye i sanitarnaya tekhnika.-2010.- № 6.- S. 33-38. [. Akhmedov G.Ya. Stabilization treatment of geothermal waters // Water supply and sanitary engineering .- 2010.- № 6. pp. 33-38. (in Russ)]

14. Akhmedov G.YA. K voprosu o vliyanii teploperedachi na otlozheniye tverdoy fazy karbonata kal'tsiya na teploobmennoy poverkhnosti //Energosberezheniye i vodopodgotovka. 2011. № 6. pp. 6 – 8. [ (in Russ)]

15. Geotermal'noye teplokhladosnabzheniye zhilykh i obshchestvennykh zdaniy i sooruzheniy. VSN 56-87. Normy proyektirovaniya. – M.: Stroyizdat, 1989. 50 p. [(in Russ)]