Efficiency Enhancement of Gas Turbine Systems with Air Injection Driven by Natural Gas Turboexpanders

Sustainability

Reza Shirmohammadi¹  Fontina Petrakopoulou²  Ali Rafiei Sefiddashti³ 

[1] Department of Renewable Energies and Environment, Faculty of New Sciences & Technologies, University of Tehran, Tehran 14174-66191, Iran;Department of Thermal and Fluid Engineering, University Carlos III of Madrid, 28911 Madrid, Spain;Faculty of Mechanical Engineering, Babol Noshirvani University of Technology, Babol 47148-71167, Iran;

关键词: gas turbine;    air injection;    turboexpander;    performance enhancement;    emission reduction;   

DOI  :  10.3390/su131910994

来源: DOAJ

【 摘 要 】

The fuel source of many simple and combined-cycle power plants usually comes from a nearby natural gas transmission pipeline at a pressure from 50 to over 70 bar. The use of a turboexpander instead of throttling equipment offers a promising alternative to regulate the pressure of natural gas introduced to the power plant. Specifically, it helps recover part of the available energy of the compressed gas in the transmission pipeline, increase the power output and efficiency of the gas turbine system, and decrease the fuel use and harmful emissions. In this paper, the addition of such a turboexpander in a gas pressure-reduction station is studied. The recovered power is then used to drive the compression of extra air added to the combustion chamber of a heavy-duty gas turbine. The performance of this configuration is analyzed for a wide range of ambient temperatures using energy and exergy analyses. Fuel energy recovered in this way increases the output power and the efficiency of the gas turbine system by a minimum of 2.5 MW and 0.25%, respectively. The exergy efficiency of the gas turbine system increases by approximately 0.36% and the annual CO₂ emissions decrease by 1.3% per MW.

【 授权许可】

Unknown