Parametric and thermodynamic analysis of electricity production in gas pressure reduction stations using turbo expanders based on geothermal energy

Paying attention to the environmental hazards of traditional energies, especially the phenomenon of global warming caused by the release and concentration of greenhouse gases, is one of the main reasons for paying attention to new energies and it has prompted the governments to seriously put the benefit of new sources of energy on the agenda and plan for it. On the other hand, it is appropriate that existing potentials such as energy loss due to gas pressure reduction in urban gas reduction stations should be considered and investigated. Therefore, in this article, it has been tried to produce electricity by using a turbo expander in a municipal gas pressure reduction station. The gas input to this turbo expander is also preheated by geothermal energy to increase the work production capacity. The results indicate that the most ideal isentropic efficiency (equal to 90%) occurs at the turbo expander inlet temperature equal to 80 degrees Celsius and the amount of preheating equal to 186.5 kJ/kg. Also, increasing the amount of natural gas preheating increases the temperature of the expansion turbine and as a result, the production power increases.