(19b) Development of Solvent-Free Process for FLNG Pretreatment Application

Offshore LNG production on a floating platform (FLNG) offers a cost effective way to develop natural gas fields remote from land and pipeline infrastructure.  There are over 800 such “stranded” gas fields worldwide with reserve in the range of 0.5~2 trillion cubic feet, which are ideal for FLNG projects. In recent years, interest in developing FLNG solutions to monetize off-shore stranded gas has rapidly grown and FLNG is now considered at the forefront of offshore industry focus. The liquefaction and related offshore technologies have also advanced to a point that FLNG projects have become technically viable.

UOP has several technologies that are well suited for acid gas removal or pretreatment of FLNG.  A new FLNG pretreatment system has recently been developed by UOP. The new process uses UOP’s Separex™ membrane for bulk removal of CO₂ (as well as water and H₂S), followed by UOP’s MolSiv™ adsorption unit for final polishing to reach the product specification of less than 50 ppm CO₂. This new process not only eliminates the amine solvent unit, but it also employs commercially proven technologies with off-shore experience. It is anticipated that this process will be more robust than other solutions with respect to the sea motion and more flexible to the variation of the feed gas supply. The benefits of this new process will be discussed in this paper.