THE OPERATION OF POWER EQUIPMENT DURING THE DISPOSAL OF COMBUSTIBLE GASES ASSOCIATED WITH GEOTHERMAL WATER

Abstract

Objectives. The aim of the study is to assess the appropriateness of utilising combustible gases associated with geothermal water with low gas factor and the possibility of its practical implementation with the provision of power equipment operation of geothermal systems with a nonscaling mode. Methods. The investigations were carried out by analysing the content of associated combustible gases in the underground thermomineral waters of the Cis-Caucasian deposits on the basis of an assessment of the feasibility of their utilisation for heating and hot water supply. Results. A review of practically existing heat and power schemes utilising geothermal water sources is carried out. Based on the studies conducted, it is found that methane (70-90%) is prevalent in the water under consideration; meanwhile, the content of heavy hydrocarbons does not exceed 10%. The concentration of carbon dioxide is 3 ÷ 6%, nitrogen 1 ÷ 4%. Depending on the depth of the aquifer, gas factors range from 1 to 5 m3/ m3. As a result of the analysis of the operation of typical thermal distribution stations, it is established that a violation of the carbon dioxide equilibrium in water leads to the formation of a solid phase of calcium carbonate on the heat exchange surface. A technique for estimating the relationship between the partial pressure of methane and carbon dioxide with the total pressure in a solution of geothermal water is proposed. A scheme for the efficient operation of thermal distribution stations with the prevention of carbonate deposits formation by using the combustion products of the used gas combined with the injection of waste water back into the aquifer is presented. Conclusion. As a result of the conducted studies, the possibility of using associated combustible gases in geothermal wells is established using differences in their solubility and that of carbon dioxide. In this case, the protection of heat exchange equipment and the well from solid deposits of calcium carbonate can be achieved by using combustion products of associated combustible gases.