Membrane degassing and de-bubbling applications fall into the technical class of gas/liquid separation. Degassing and de-bubbling are processes in which dissolved gases (degassing) or bubbles are pulled out of solution, either from aqueous or organic liquids. The dissolved gas or bubbles may be oxygen, nitrogen, carbon dioxide, i.e. gases in the conventional sense or they may be volatile organic compounds (VOCs) which are present in trace quantities in aqueous systems and are pulled out as a vapor. For degassing and debubbling organic systems, pervaporation would most likely be the preferred technology.
Liquid streams generally require degassing or debubbling to protect some downstream process or piece of equipment. Analytical equipment and drug delivery systems require debubbling as the bubbles interfere with the sensitive flow or analytical detection systems downstream. Aqueous systems may require purification by removal of volatile organic compounds or removal of dissolved gases either to generate potable water or to purify the water for subsequent processing use. The semi-conductor industry employs significant numbers of degassing systems for their ultra pure water systems. Bubbles present during chip and wafer manufacture result in costly defects. Beverages are degassed to pull out CO2 and replace it with N2, ink jet printers would benefit from degassing by allowing higher print speeds, and boiler systems require degassing the water to avoid pitting and corrosive action from heated dissolved gases, especially CO2.
The key to the effective performance of a degassing or debubbling module is maintaining the liquid on one side of the membrane and the gaseous discharge on the other. This requires a highly hydrophobic membrane, a feature where PTFE has no equal. The natural hydrophobicity of PTFE combined with the thermal stability, chemical inertness of PTFE and the Eclipse Hollow Fiber Membrane® potting system makes them ideal degassing and debubbling contactors for higher temperature or aggressive aqueous systems.
Markel has developed a family of modules utilizing their proprietary potting technologies for both filtration and contacting applications. Please contact Markel to discuss your specific needs concerning Gas Liquid Contacting and Separations applications.