SUSTAINABLE DESIGN AND ANALYSIS FOR GASOLINE PRODUCED FROM GTL AND MTG PROCESSES: PROCESS SIMULATION, TECHNO-ECONOMIC, AND ENVIRONMENT ASSESSMENT

Abstract

The global energy demand will continue to expand as the world population grows. Energy and environmental concerns are closely related since it is nearly difficult to create, transfer, or consume energy without having a significant environmental impact. Thus, the use of clean and effective energy resources such as Natural gas (NG) shows less environmental impact, contributes to solving the global warming problem and reducing the emissions compared to the other conventional fossil fuels (Coal and Oil). This thesis investigates the comparative analysis of gas to liquid (GTL) and methanol to gasoline (MTG) processes. The focus is to optimize the production of gasoline from both processes. Aspen HYSYS V.11 simulation software was used to simulate the MTG and GTL low and high-temperature configurations. An equal amount of NG at 15372.37 Tonne/d is used in all cases. After performing the steady-state simulation, a sensitivity analysis was performed on the GTL process to maximize the gasoline production yield at different chain growth probability (α) for both high Fischer Tropsch (HTFT) and low Fischer Tropsch (LTFT) processes. Moreover, the simulated flowsheets were examined from an environmental, and economic point of view . Results reveled that the maximum gasoline production was achieved at α = 0.78 for HTFT and α = 0.88 for LTFT. The study findings demonstrate a higher gasoline production from the MTG plant of 5345 Tonne/d compared 4798 Tonne/d from HTFT, whereas 2896 Tonne/d was produced from LTFT plant. In addition, the economic analysis revealed that the net profit per product for the MTG process is greater, at $1345tonne of product⁄ compared to $981tonne of product⁄ form the LTFT and $879Tonne of product⁄ form the HTFT. Similarly, the CO2 emissionsTonne of product ⁄from the MTG plant was lower with 0.48 tons of CO2 equivelenttonne of product⁄ compared with 1.76 and 1.50 tons of CO2 equivelentproduct⁄ from LT-FT and HTFT. Moreover, the capital cost of LTFT, HTFT, and MTG were estimated as 74.7 million USD, 85.5 million USD and 109.2 million USD respectively. Moreover, the operating cost were valued as79.6 million USD, 102.5 million USD, and 47.8 million USD respectively.