Membrane gas dehydrating apparatus for gas controlled and powered systems

An apparatus for dehydrating air in a pneumatically controlled and powered trailer braking system having control air and supply air, the apparatus comprising:

• a first membrane member comprising a plurality of tubes having interstitial spaces therebetween, and defining a flow path for the supply gas;
• a second membrane member comprising a plurality of tubes having interstitial spaces therebetween, and defining a flow path for the supply gas;
• and
• means for directing a portion of the supply gas through the interstitial spaces of said first and second membrane members.

An apparatus for dehydrating air in a pneumatically controlled and powered trailer braking system having control air and supply air, the apparatus comprising:

• a first portion of a unitary housing having a first inlet and a first outlet and a flow path therebetween, each of the first inlet and first outlet adapted to be connected to the supply air, the first housing portion further having a first vent;
• a first membrane member disposed within the first housing portion and in the flow path, and comprising a plurality of tubes having interstitial spaces therebetween, each tube being more permeable to water vapor than to air, wherein after the supply air has passed through the first membrane member, the supply air becomes substantially dehydrated supply air;
• a plenum disposed in the flow path between the first membrane member and the first housing portion outlet;
• a first metering orifice, in fluid communication with the plenum and the first membrane member interstitial spaces, for channeling a first predetermined portion of substantially dehydrated supply air to the first membrane member interstitial spaces, whereby the substantially dehydrated supply air portion sweeps at least one of water and water vapor from the first membrane member interstitial spaces to the surrounding environment through the first vent;
• a second portion of a unitary housing having a second inlet and a second outlet and a flow path therebetween, each of the second inlet and second outlet adapted to be connected to the control air, the second further having a second vent;
• a second membrane member disposed within the second housing portion and in the second housing portion flow path, and comprising a plurality of tubes having interstitial spaces therebetween, each tube being more permeable to water vapor than to air, wherein after the control air has passed through the second membrane member, the control air becomes substantially dehydrated control air;
• a flow channel defined in the second housing portion and in fluid communication with the second membrane member interstitial spaces;
• and
• a second metering orifice, in fluid communication with the plenum and the flow channel, for directing a second predetermined portion of substantially dehydrated supply air to the second membrane member interstitial spaces, whereby the substantially dehydrated supply air portion sweeps at least one of water and water vapor from the second membrane member interstitial spaces through the second vent;
• wherein each of the plurality of tubes in each of the first and second membrane members is a hollow fiber formed from a permeable material;
• and wherein each of the first and second membrane members further comprise two opposed polymeric tubesheets, one adjacent the respective housing portion inlet, and the other adjacent the respective housing portion outlet, wherein the tubesheets orient the respective plurality of tubes therein and allow fluid communication between the respective tubes and the respective inlet and outlet, while disallowing fluid communication between the respective interstitial spaces and the respective inlet and outlet.

A method for dehydrating gas in a gas controlled and powered system having a control gas and a supply gas, the method comprising the steps of:

• passing supply gas through a first membrane member comprising a plurality of tubes having interstitial spaces therebetween, wherein after the supply gas has passed through the first membrane member, the supply gas becomes substantially dehydrated supply gas;
• channeling a first predetermined portion of substantially dehydrated supply gas to the first membrane member interstitial spaces, whereby the substantially dehydrated supply gas portion sweeps at least one of water and water vapor from the first membrane member interstitial spaces to the surrounding environment;
• passing control gas through a second membrane member comprising a plurality of tubes having interstitial spaces therebetween, wherein after the control gas has passed through the second membrane member, the control gas becomes substantially dehydrated control gas;
• directing a second predetermined portion of substantially dehydrated supply gas to the second membrane member interstitial spaces, whereby the substantially dehydrated supply gas portion sweeps at least one of water and water vapor from the second membrane member interstitial spaces.

An apparatus for dehydrating gas in a gas controlled and powered system having a control gas and a supply gas, the apparatus comprising:

• a first membrane member comprising a plurality of tubes having interstitial spaces therebetween, and defining a flow path for the supply gas;
• a second membrane member comprising a plurality of tubes having interstitial spaces therebetween, and defining a flow path for the supply gas;
• and
• one or more a metering orifices for directing a portion of the supply gas through the interstitial spaces of said first and second membrane members.