NATURAL GAS LIQUEFACTION WITH INTEGRATED NITROGEN REMOVAL

• Main Authors: ROBERTS MARK J, ANNEMARIE OTT WEIST, OTT CHRISTOPHER MICHAEL, CHEN FEI
• Format: Patent
• Language: English; Japanese
• Published: 20.02.2020
• Subjects: BLASTING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; HEATING; LIGHTING; LIQUEFACTION SOLIDIFICATION OF GASES; LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS; MANUFACTURE OR STORAGE OF ICE; MECHANICAL ENGINEERING; MIXTURES BY PRESSURE AND COLD TREATMENT; REFRIGERATION OR COOLING; WEAPONS

To provide a natural gas liquefaction method and system having integrated nitrogen removal.SOLUTION: Recycled LNG gas is cooled in a circuit separate from and parallel to a natural gas stream in a main heat exchanger. Cooled recycled gas and natural gas streams are directed to a nitrogen rectifier column after a warm bundle. The recycle stream is introduced to the rectifier column above the natural gas stream, and at least one separation stage is located in the rectifier column between a recycle stream inlet and a natural gas inlet. The bottom stream from the rectifier column is directed to a cold bundle of the main heat exchanger and subcooled there.SELECTED DRAWING: Figure 1 【課題】窒素除去を統合させた天然ガス液化方法およびシステムの提供。【解決手段】リサイクルされるＬＮＧガスは、主熱交換器内の天然ガス流とは別にかつ天然ガス流と平行な回路内で冷却される。冷却された、リサイクルされるガス流および天然ガス流は、暖かい管束の後方の窒素精留塔に導かれる。リサイクル流は、天然ガス流の上方の精留塔に導入され、少なくとも１つの分離ステージが、精留塔内のリサイクル流入口と天然ガス入口との間に位置付けられている。精留塔からの底部流は、主熱交換器の冷たい管束に導かれ、そこで過冷却される。【選択図】図１