CRYOGENIC MULTIPLE BED BASED DEHYDRATION AND CO2 SEPARATION DURING PURIFICATION OF NATURAL GAS

• Main Author: Wen Wen, Karen Hii
• Format: Final Year Project
• Language: English
• Published: Universiti Teknologi PETRONAS 2013
• Subjects: TP Chemical technology
• Online Access: http://utpedia.utp.edu.my/8463/1/Hard%20Bound%20Farouk.pdf; http://utpedia.utp.edu.my/8463/

A novel concept of separation of water and CO2 from natural gas is presented in this work using multiple cryogenic packed beds. The principle separation of water and CO2 from natural gas is the difference in the desublimation of components in natural gas. Experimentation is conducted based on dehydration and CO2 removal from natural gas while simulation is carried out to validate the result. A series of pre cooled bed for effective separation between water, CO2 and natural gas can be used periodically. The dehydration unit is kept slightly below the freezing point of water which desublimates water upon passing the wet gas and the remaining components do not undergo phase change. The same concept is also applied for CO2 removal from natural gas using cryogenic packed bed. It is worthy notable that CO2 undergoes phase change from gas to solid and there is no chemical reaction involved. The 1-dimensional pseudo homogeneous model is used to describe the process for desublimation of both water and CO2. Furthermore, the concentration and temperature distribution during dehydration and CO2 removal from natural gas at cryogenic temperature are investigated in detail. The optimization of operating conditions of multiple cryogenic beds based on dehydration and CO2 removal is analyzed. The resulting simulation shows the good resemblance with the developed model.