| Popis: |
This preliminary study discusses the option of using silicone (PDMS) tubes for the extraction and monitoring of CH 4 gas from hydrate deposits during decomposition. For this, the gas flow of gaseous and dissolved CH 4 through hand-manufactured silicone tube membranes has been tested on a small lab scale. The permeability of pure CH 4 gas at ambient pressure and 295K is in good agreement with literature reports. The permeability rate of CH 4 derived from dissolved methane is expectedly lower and decreases by more than half. Theoretical assumptions and lab results are not in straightforward correlation. This leads to the conclusion that experimental constraints influence the permeability. These are mainly an increase of the gas stream resistivity due to the membrane-filling and membrane-sediment contact points as well as the effect of degassing dissolved CH 4 on the tube surface due to pressure gradients. Therefore, the use as a monitoring tool needs to be individually tested before the respective application. Due to the robust nature of the membranes, their application as a tool for capturing gaseous CH 4 during hydrate decomposition is a feasible goal. |
