WORLD'S FIRST APPLICATION OF GAS TURBINE INLET AIR CHILLING FOR LNG LIQUEFACTION - DESIGN, IMPLEMENTATION AND OPERATION

摘要

This paper describes the design, implementation, startup and operation of the world's first application of GT inlet air chilling for LNG liquefaction at BG Group's two 4.25 MTPA Queensland Curtis LNG (QCLNG) train facility in Australia. Twelve high efficiency aeroderivative gas turbines utilize a propane based inlet air chilling system with chilled water being deployed in coils in the gas turbine inlet ducts. LNG liquefaction plants benefit significantly due to the inlet air chilling of the refrigeration compressor drivers. Aeroderivative gas turbines exhibit a drop in power output with increasing ambient air temperature on the order of 1% per °C and consequently inlet chilling is an attractive approach to increase production and minimize daily and seasonal production swings. Operating at lower GT compressor inlet air temperatures also results in an improvement of gas turbine thermal efficiency. This paper discusses the design, selection of chilling system and the selection of climatic points (ambient temperatures and relative humidity) to be used for the chiller plant design. The choice of refrigerant, design for redundancy and the parasitic power consumption will be covered along with the techno-economic benefits of inlet air chilling. Operating experience with inlet air chilling (IAC) over the past year on two trains has successfully demonstrated the validity and effectiveness of the concept for LNG liquefaction.