METHOD AND SYSTEM FOR EFFICIENT NONSYNCHRONOUS LNG PRODUCTION USING LARGE SCALE MULTI-SHAFT GAS TUSBINES

INTERNATIONAL APPLICATION PUBLISHED UNDER THE PATENT COOPERATION TREATY (PCT) (19) World Intellectual Property Organization International Bureau (43) International Publication Date 22 November 2018 (22.11.2018) WIPO I PCT 011101010 VIII OH o 10010111 VIII OH mil 0111110 111110 oimIE (10) International Publication Number WO 2018/212830 Al (51) International Patent Classification: F25J 1/00 (2006.01) F25J 1/02 (2006.01) (21) International Application Number: PCT/US2018/024037 (22) International Filing Date: 23 March 2018 (23.03.2018) (25) Filing Language: English (26) Publication Language: English (30) Priority Data: 62/506,922 16 May 2017 (16.05.2017) US 62/570,998 11 October 2017 (11.10.2017) US (71) Applicant: EXXONMOBIL UPSTREAM RESEARCH COMPANY [US/US]; (EMHC-E2-4A-296), 22777 Springwoods Village Parkway, Spring, TX 77389 (US). (72) Inventors; and (71) Applicants (for US only): GUY, Ashley R. [US/US]; 1302 Waugh Drive #732, Houston, TX 77019 (US). LUPASCU, Sorin T. [US/US]; 6610 Pelham Chase Drive, Spring, TX 77389 (US). PARKER, Donna J. [US/US]; 103 Trinity Oaks Circle, The Woodlands, TX 77381 (US). LEE, Yow- Yeen [MY/US]; 39 Pebble Cove Drive, The Woodlands, TX 77381 (US). (74) Agent: JENSEN, Nathan 0. et al.; Exxonmobil Upstream Research Company, (EMHC-E2-4A-296), 22777 Spring- woods Village Parkway, Spring, TX 77389 (US). (81) Designated States (unless otherwise indicated, for every kind of national protection available): AE, AG, AL, AM, AO, AT, AU, AZ, BA, BB, BG, BH, BN, BR, BW, BY, BZ, CA, CH, CL, CN, CO, CR, CU, CZ, DE, DJ, DK, DM, DO, DZ, EC, EE, EG, ES, FI, GB, GD, GE, GH, GM, GT, HN, HR, HU, ID, IL, IN, IR, IS, JO, JP, KE, KG, KH, KN, KP, KR, KW, KZ, LA, LC, LK, LR, LS, LU, LY, MA, MD, ME, (54) Title: METHOD AND SYSTEM FOR EFFICIENT NONSYNCHRONOUS LNG PRODUCTION USING LARGE SCALE = MULTI-SHAFT GAS TUSBINES 400 402 \s,, .. 442 412 422 432 404 444 414 424 434 406 l y 446 416 426 436 FIG. 4 cc 00 O O (57) : A drive system for liquefied natural gas (LNG) refrigeration compressors in a LNG liquefaction plant. Each of three refrigeration compression strings include refrigeration compressors and a multi-shaft gas turbine capable of non-synchronous operation. The multi- shaft gas turbine is operationally connected to the refrigeration compressors and is configured to drive the one or more refrigeration compressors. The multi-shaft gas turbine uses its inherent speed turndown range to start the one or more refrigeration compressors from rest, bring th