Loading...

Process Design of Ionic Liquid-Based CO2 Capture with Consideration of Economic and Environmental Issues

Eidi, Ali | 2019

610 Viewed
  1. Type of Document: M.Sc. Thesis
  2. Language: Farsi
  3. Document No: 52601 (06)
  4. University: Sharif University of Technology
  5. Department: Chemical and Petroleum Engineering
  6. Advisor(s): Rashtchian, Davood; Adibi, Mina
  7. Abstract:
  8. Concerns have increased about global warming caused by CO2 emissions in the atmosphere. At the moment, carbon capture and storage is the best available solution. Among the current technologies for CCS, amine-based chemical absorption appears to be the most common method. Amines show several inherent drawbacks such as high vapor pressure, high energy consumption in regeneration, corrosivity and degradability. So, researchers have developed new solvents with the foresight of being superior to amines. Ionic liquids (ILs) are among the most suitable alternatives. The most prominent feature of ILs is their tunable thermophysical properties. In this work, physical absorption by ILs is chosen as the separation method. Among the twenty different suggested ILs for CCS, 1-butyl-3-methylimidazolium hexafluorophosphate ([bmim [PF6]) and 1-hexyl-3-methylimidazolium is(trifluoromethanesulfonyl)imide ([hmim][TF2N]) are selected as the most appropriate solvents in this work. Solvent selection is based on some of IL’s features, which affect the process significantly. Two distinct processes are designed in this work. Their difference is in the absorption column’s operating conditions. One of them uses cooling water for refrigeration, while another uses moderately low-temperature Refrigerated water. These processes are simulated in Aspen Plus with both solvents. The second process which uses cooling water as a refrigerant needs three compressors to satisfy separation constraints. The other process uses two compressors. The first process consumes more energy unexpectedly. However, Purchased equipment costs are higher for the second process. In general, this study illustrates that the second process is better than the first one in terms of economic, environmental and process performance. Also, this research shows that units with [hmim][TF2N] as the solvent, are better than units that are used [bmim][PF6]. Three various feed conditions are considered for flue gas. Then, the designed processes in this work are compared with other processes that are presented by other researchers. According to a comparative approach, This paper confirms that the first process with [hmim][TF2N] as the solvent, the second process with [hmim] TF2N] as the solvent and the second process with [bmim][PF6] as the solvent have the best performance among designed processes in the first, second and third comparison respectively. It could be concluded that designed processes in this project consume much lower thermal energy compared to other reference processes while they consume more electrical energy. Purchased equipment costs and solvent’s costs are more economical for the designed processes in this work. Generally, this project substantiates that the designed processes are better than previously designed processes by other researchers in terms of performance and economic
  9. Keywords:
  10. Carbon Dioxide Capture ; Ionic Liquids ; Simulation ; Greenhouse Gases ; Global Warming ; Weather Change ; Power Plant Flue Gas

 Digital Object List

 Bookmark

No TOC