Patent ID: 7494114

Claim:
A system for providing blended fluids at a specified minimum delivery pressure, the system comprising: a differential pressure regulator having a high pressure side, a low pressure side, and a pressure reference port; a second fluid source containing a second fluid at a second fluid pressure, where the second fluid source is connected to the high pressure side of the differential pressure regulator; at least one controlled temperature reservoir with each controlled temperature reservoir containing a first fluid at a controlled first fluid temperature; an output line having an output line first end and an output line second end; at least one fluid carrier with each fluid carrier having a permeable section and with each fluid carrier having a fluid carrier first end and a fluid carrier second end, where the fluid carrier first end of each fluid carrier is connected to the low pressure side of differential pressure regulator, and where a portion of each permeable section is immersed in at least one controlled temperature reservoir, and where the fluid carrier second end of each fluid carrier is connected to the output line first end, whereby as the second fluid passes through the portion of each permeable section of fluid carrier that is immersed in the first fluid in the controlled temperature reservoir, a portion of the first fluid passes through the permeable section of the fluid carrier and mixes with a portion of the second fluid forming a blended fluid that flows from the fluid carrier second end into the output line first end at a blended fluid output pressure; a back pressure control valve tapped into the output line, where the back pressure control valve is set at a back pressure that is at least equal to the specified minimum delivery pressure; and a pilot tube having a pilot tube first end and a pilot tube second end, where the pilot tube first end is tapped into the output line, and the pilot tube second end is connected to the pressure reference port of the differential pressure regulator whereby the blended fluid output pressure remains substantially constant and blended fluid flows from the output line second end at a volumetric mixture ratio that is substantially determined by the first fluid temperature of each controlled temperature reservoir.