Liquefied natural gas re-gasification cold energy hybrid system integration in gas-steam combined cycle power plant model: Enhancement in power generation and performance

摘要

The liquefied natural gas (LNG) cold energy utilization for inlet air cooling (IAC) to augment combined cycle power output is widely recognized as a feasible and sustainable alternative. However, issues with flexible operation and hybrid system integration still remain in warm climate region. To take the edge off from such kind of issues and to enhance the power generation and the performance, few possible opportunities are explored for a gas-steam combined cycle power plant (CCPP) with thermal integration of LNG re-gasification cold energy. Three integration approaches, such as 1st gas turbine IAC, 2nd condenser water cooling (CWC) in steam turbine cycle and 3rd combined approach of both IAC and CWC are proposed. Thermodynamic modeling and simulation-based method is adapted for CCPP model identification and thermodynamic performance comparison. Moreover, the results are established as a function of relative humidity and ambient temperature along with off design power generation of the proposed system. The result shows that the CCPP relative power improved from 1.01% to18.48% (for third integration approach) and 0.17% to 0.217% (for second integration approach), in the ambient temperature range of 13-45. C and relative humidity of 90-40% respectively, compared to that of non-integrated CCPP. In third integration approach the relative efficiency enhancement is observed in the range of 0.05-0.40%, particularly in higher range of ambient conditions. In second integration approach the CCPP efficiency enhanced from 0.17% to 0.22% in ambient temperature range of 13-45 degrees C and relative humidity 40-90%.