An Analysis of Energy Consumption and Environmental Impact on the Emissions of Carbon Dioxide and Methane of the Offshore Natural Gas Liquefaction Process in Facilities with Utilizing Dual Mixed Refrigerant (DMR) Process Technology

The objective of this thesis is to evaluate the effects of the dual mixed refrigerant (DMR) process on energy consumption and greenhouse gas (GHG) emissions in terms of carbon dioxide (CO2) and methane (CH4) in an offshore liquid natural gas (LNG) facility based on the reliable data from the Gulf of Mexico in the United States. After comparing energy consumption and GHG (carbon dioxide and methane) emissions for a number of liquefaction technologies: including mixed fluid cascade (MFC), dual mixed refrigerant (DMR), single mixed refrigerant (SMR), mixed refrigerant with propane precooling (C3MR), and the Conoco Phillips Optimized Cascade processes, the evaluation showed that dual mixed refrigerant (DMR) process features both high energy consumption and high GHG (carbon dioxide and methane) emission in regards to the liquefaction process. With this result in mind, more technical enhancement is needed to update the DMR process to decrease energy consumption, and more research is needed to support the reduction of negative environmental impacts in the future. The results of this thesis will benefit research on the liquefaction process regarding energy consumption and environmental impacts.