(50b) Transient Characteristics of Two-Phase LNG Expanders

Authors: 
Finley, C. D. - Presenter, Ebara International
Chiu, C. H. - Presenter, ChevronTexaco- Energy Research & Technology
Cholast, K. - Presenter, KRIO Polish Oil and Gas
Kociemba, A. - Presenter, KRIO Polish Oil and Gas
Kimmel, A. - Presenter, University of Nevada at Reno


For optimized LNG production, particularly to reduce liquefaction costs or to extend the lifetime of depleting gas fields, it was previously suggested to use two-phase LNG expanders operating in series with a single-phase liquid LNG expander. While the performance of liquid expanders depends only on mass flow and differential head, the performance of two-phase expanders depend on additional properties like LNG composition, temperature, and outlet pressure. The effect of non-linear oscillations and of transient operation on the performance of two-phase LNG expanders operating in series with single-phase LNG expanders is discussed and presented.