Intervening when feed gas is too lean: Heavies removal challenges for LNG projects

Pipeline-quality feed gas for US LNG projects poses a unique challenge: heavy hydrocarbon removal. If not removed, these heavy hydrocarbons will freeze out during the liquefaction process.

Unfortunately, for lean feed gas, traditional hydrocarbon removal methods may not meet all required liquefaction specifications.

This paper reviews proven technologies that show benefits for heavy hydrocarbons removal systems for lean feed compositions. The discussion includes an analysis among heavy hydrocarbons removal technologies using a case study approach which considers different ranges of feed gas compositions and delineates an optimal selection for each composition. The paper also highlights relative capital and operating expenditures estimations among different technologies and the significant impacts to liquefaction process efficiency.