STRATEGIES TO INCREASE PRODUCTION AND ENERGY EFFICIENCY OF A BASELOAD LNG PLANT

Abstract

This work first improves the energy efficiency of a conventional LNG plant with attention to heat integration of various streams from the cold section. The cold section consists of LNG liquefaction, natural gas liquid recovery, nitrogen removal unit (NRU), and export terminal. Two configurations for NRU are considered and the specific power requirement of the entire cold section is minimized. Then the acid gas removal unit is incorporated in the cold section by solidifying the acid gases at freezing conditions. The aim is to design and optimize an energy-integrated and self-sustained cryogenic process incorporating the AGRU, liquefaction unit, NGL recovery unit, NRU, and export terminal. Finally, the concept of “upfront nitrogen removal” in a baseload LNG plant is investigated. The potential energy savings and increase in LNG output are quantified. Finally, the lithium cycle is considered a viable upfront nitrogen removal technology, and a rigorous techno-economic analysis is carried out.