Transversal Submerged Membrane Contactor for Simultaneous Absorption and Desorption of CO2 During Natural Gas Sweetening Process

• Published in: IOP conference series. Materials Science and Engineering 2018-01, Vol.395 (1)
• Main Authors: Siagian, U W R, Rahmawati, Y, Khoiruddin, K, Hakim, A N, Wenten, I G
• Format: Article
• Language: English
• Subjects: Absorption; Carbon dioxide; Configurations; Desorption; Flow velocity; Gas flow; Hollow fiber membranes; Modules; Natural gas; Separation; Solvents; Wetting
• ISSN: 1757-8981; 1757-899X
• DOI: 10.1088/1757-899X/395/1/012013

In this work, a unique transversal submerged membrane contactor is used for CO2 removal. The developed configuration is aimed to provide the possibility to perform simultaneous absorption and desorption of carbon dioxide in a single module. In addition, this configuration is expected to reduce the solvent circulation which is the major obstacle encountered in separated absorption-desorption unit. The module contains a number of polypropylene hollow fiber membranes arranged perpendicularly to the longitudinal axis in which the fibers are submerged into a solvent. Pure water which is placed in the shell of the module is used as the solvent. The effects of operating parameters such as gas flow rate (40-80 ml/min) and operating time on membrane performance are investigated. In addition, the simultaneous absorption-desorption process is compared to the separated ones. Results revealed that CO2 removal is significantly affected by the gas flow rate. The optimum gas flow rate is 60 ml/min (vacuum pressure of 60.5 kPa) with >80% CO2 absorption and desorption efficiencies. During a long-term operation, the separation efficiencies are decreased after 200 minutes of operation which may be associated with membrane wetting phenomenon. The simultaneous absorption-desorption process shows a higher separation efficiency rather than the separated process.