System for the transfer and detection of gas dissolved in fluid under pressure ii

Abstract

A gas separation system suited for extraction of gas dissolved in pressurized fluid. The system includes a semi-permeable membrane in the form of tubing having an inner core volume with an internal support present within the inner core volume. The internal support provides multiple cylindrical supporting surfaces which are presented to the inside tubing wall surface to prevent collapse of the tubing wall against external pressure. Internal supports may include a coil of spring-like configuration fitted coaxially within the tubing; or multiple filaments that form a longitudinal bundle within the core of the tubing. The response time of the system may be enhanced by the presence of an outer tubular conduit surrounding the semi-permeable membrane tubing and providing a flow path for the external fluid to increase the rate of diffusion of dissolved gases through the semi-permeable membrane. Gas pressures may be a sensed, both total and partial, as well as the identity of respective sampled gases.

1 . A system for effecting the transfer of gas dissolved in fluid under pressure comprising:
 a) a semi-permeable membrane admitting the transfer of gas while substantially excluding the penetration of fluid, such membrane being in the form of tubing having an outside surface, a tubing wall, and inside tubing wall surface and an inner core volume; and   b) an internal support present within the inner core volume, the internal support having multiple cylindrical supporting surfaces which are presented to the inside tubing wall surface to provide support for said tubing wall against a pressure differential existing between the exterior of the tubing wall and the inner core volume,   whereby gas dissolved in the fluid when present outside the tubing wall may pass through the tubing wall into the inner core volume.   
   
   
       2 . A system as in  claim 1  wherein said internal support comprises a coil of spring-like configuration fitted coaxially within the tubing. 
   
   
       3 . A system as in  claim 1  wherein said internal support comprises multiple filaments that form a longitudinal bundle containing longitudinal channels that provide interstitial sub-volumes between adjacent filaments of the longitudinal bundle to constitute said inner core volume. 
   
   
       4 . A system as in any one of  claims 1 ,  2 , or  3  in combination with a sample gas circulation means communicating with the inner core volume for carrying gas present therein to said gas sensor. 
   
   
       5 . A system as in any one of  claims 1 ,  2 ,  3  or  4  further comprising:
 a) an outer tubular conduit surrounding the semi-permeable membrane tubing and providing a flow path for the fluid to follow that is adjacent to the outside surface of said tubing; and,   b) external fluid circulating means to cause the fluid to pass along said flow path and thereby increase the rate of mass transfer of dissolved gases through the semi-permeable membrane.   
   
   
       6 . A system as in  claim 5  wherein the flow path is an annular flow path and wherein said annular flow path comprises a helically formed baffle present therein. 
   
   
       7 . A system as in  claim 6  wherein the helically formed baffle has a width that occupies the space between the outer tubular conduit and said tubing 
   
   
       8 . A system as in  claim 4  wherein said sensor determines the pressure of the gases present in the sampling inner core volume. 
   
   
       9 . A gas detection system as in  claim 4  wherein said sensor identifies the character of at least one gas present within the inner core volume. 
   
   
       10 . A system for effecting the transfer of gas under pressure comprising:
 a) a semi-permeable membrane admitting the transfer of gas while substantially excluding the penetration of liquid, such membrane being in the form of tubing having an outside surface, a tubing wall, and inside tubing wall surface and an inner core volume; and   b) an internal support present within the inner core volume, the internal support having multiple cylindrical supporting surfaces which are presented to the inside tubing wall surface to provide support for said tubing wall against a pressure differential existing between the exterior of the tubing wall and the inner core volume,   whereby gas present under a given pressure outside the tubing wall may pass through the tubing wall into the inner core volume when the inner core volume is at a pressure that is lower than the given pressure.   
   
   
       11 . A system as in  claim 8  wherein a fluid is present within the inner core volume.