Process Optimization for Small Scale LNG Plants

LNG plants have recently been more sensitive to CAPEX due to plunging oil prices. An increasing trend is being noticed in reducing CAPEX at the expense of higher OPEX. Companies are willing to accrue more operating costs to justify lower CAPEX and to kick-start projects. This philosophy requires being acclimatized to lower revenues, but helps smaller operators to reduce debts. Implementation of this approach however requires significant optimization and cost benefit studies. The intent of this paper is to illustrate optimization case studies.

Small Scale LNG projects require integration of several licensed/proprietary and open-art process units, as listed below:

• Liquefaction Unit
• Gas Pre-Treatment Unit, which may include some or all of the following:
  • Dehydration (Water Removal)
  • CO2 Removal
  • Sulfur Removal
  • Heavy Hydrocarbon Recovery
  • Mercury Removal
  • Removal of other impurities (oxygen, glycol, etc.)

Depending on whether a liquefaction project is greenfield or brownfield, peak-shaver or transportation fuel, etc., various open art units may be required in the facility. Auxiliary units may include some or all of the following:

• Boil Off Gas System
• LNG Storage
• Truck Loading or Marine Loading
• Regasification Facilities
• Feed Gas Compression

Process optimization of these units is critical for the success of a Liquefaction project. A host of supporting case studies will be presented to demonstrate various technically and economically effective solutions.