Liquid filled pressure/vacuum valve for petroleum underground storage tanks

Abstract

A liquid filled pressure/vacuum valve for underground storage tanks has a body having an inlet coupled to the UST and an outlet coupled to atmosphere. The valve has a suction zone disposed in the body and fluidly coupled to the inlet. The valve has a pressure zone disposed in the body and fluidly coupled to the outlet, with the suction zone in fluid communication with the pressure zone. The valve has a separator disposed in fluid communication with the outlet and the pressure zone, and a fluid that flows between the suction zone and pressure zone. The flow of fluid is determined by an increased force due to a pressure differential between the suction zone and pressure zone.

1 . A liquid filled pressure/vacuum valve for underground storage tanks comprising:
 a body having an inlet coupled to the underground storage tank and an outlet coupled to atmosphere;   a suction zone disposed in said body and fluidly coupled to said inlet;   a pressure zone disposed in said body and fluidly coupled to said outlet, said pressure zone in fluid communication with said suction zone;   a separator disposed in fluid communication with said outlet and said pressure zone; and   a fluid disposed in said body and configured to flow between said suction zone and said pressure zone, said flow of said fluid is determined by an increased force due to a pressure differential between said suction zone and said pressure zone.   
     
     
         2 . The liquid filled pressure/vacuum valve of  claim 1 , wherein said separator is configured to prevent escape of said fluid to said atmosphere and to return said fluid to said pressure zone. 
     
     
         3 . The liquid filled pressure/vacuum valve of  claim 1 , wherein said suction zone has a first wide flow passage fluidly coupled to a first narrow flow passage; and said pressure zone has a second wide flow passage fluidly coupled to a second narrow passage, said second narrow passage in fluid communication with said first narrow flow passage. 
     
     
         4 . The liquid filled pressure/vacuum valve of  claim 3 , further comprising:
 a first baffle and a second flow direction shield positioned in said body to create said first wide flow passage and said first narrow flow passage in said suction zone; and   a second baffle and a first flow direction shield positioned in said body to create said second wide flow passage and said second narrow flow passage in said pressure zone.   
     
     
         5 . The liquid filled pressure/vacuum valve of  claim 4 , further comprising:
 at least one via disposed in said first baffle and said second baffle.   
     
     
         6 . The liquid filled pressure/vacuum valve of  claim 4 , wherein a geometry of said first baffle and said second baffle are configured to achieve a desired operational setting for the liquid filled pressure/vacuum valve of about 6 inches to about 10 inches water column vacuum and about 2.5 inches to about 6 inches water column pressure. 
     
     
         7 . The liquid filled pressure/vacuum valve of  claim 1 , further comprising:
 at least one baffle disposed in the liquid filled pressure/vacuum valve to create said suction zone and said pressure zone, said at least one baffle coupled to the liquid filled pressure/vacuum valve at a position above said inlet and extending toward a bottom of the liquid filled pressure/vacuum valve.   
     
     
         8 . The liquid filled pressure/vacuum valve of  claim 7 , wherein said at least one baffle has a variable geometry to achieve a desired operational setting of about 6 inches to about 10 inches water column vacuum and about 2.5 inches to about 6 inches water column pressure for the liquid filled pressure/vacuum valve. 
     
     
         9 . The liquid filled pressure/vacuum valve of  claim 1 , further comprising:
 a test plug port disposed in said inlet.   
     
     
         10 . The liquid filled pressure/vacuum valve of  claim 1 , further comprising:
 a first sensor disposed in said suction zone; and   a second sensor disposed in said pressure zone;   wherein said first sensor and said second sensor are configured to monitor a level of said fluid.   
     
     
         11 . The liquid filled pressure/vacuum valve of  claim 1 , further comprising:
 a fluid fill port and a fluid drain port disposed in said body.   
     
     
         12 . The liquid filled pressure/vacuum valve of  claim 1 , wherein said fluid is a low vapor pressure, hydrophilic, non-foaming liquid. 
     
     
         13 . The liquid filled pressure/vacuum valve of  claim 1 , further comprising:
 at least one flange disposed in said body proximate said separator.   
     
     
         14 . The liquid filled pressure/vacuum valve of  claim 1 , wherein a desired operational setting for the liquid filled pressure/vacuum valve is about 6 inches to about 10 inches water column vacuum and about 2.5 inches to about 6 inches water column pressure. 
     
     
         15 . A liquid filled pressure/vacuum valve for underground storage tanks comprising:
 a body having an inlet coupled to the underground storage tank and an outlet coupled to atmosphere, said body having an interior opposite and exterior and a top opposite a bottom;   a first baffle coupled to said body at a position above said inlet, said first baffle configured to create a first wide flow passage and a first narrow flow passage;   a second flow direction shield physically coupled to said body at a position below said inlet, said second flow direction shield defining a portion of said first narrow flow passage;   a second baffle physically coupled to said bottom of said body, said second baffle configured to create a second wide flow passage and a second narrow flow passage, said second narrow passage is defined by said first baffle and said second baffle;   a first flow direction shield coupled to said body at a position above said first baffle, said first flow direction shield defining a portion of said second narrow flow passage;   a fluid disposed in said bottom of said body, said fluid configured to flow between said first wide flow passage, said first narrow flow passage, said second wide flow passage, and said second narrow flow passage, said flow of said fluid is determined by an increased force due to a pressure differential between said first wide flow passage and said first narrow flow passage and said second wide flow passage and said second narrow flow passage; and   a separator coupled to said body proximate said outlet, said separator configured prevent escape of said fluid to said atmosphere and to return said fluid to said second wide flow passage.   
     
     
         16 . The liquid filled pressure/vacuum valve of  claim 15 , wherein said first narrow flow passage is physically and fluidly coupled to said second narrow flow passage. 
     
     
         17 . The liquid filled pressure/vacuum valve of  claim 15 , further comprising:
 at least one via disposed in said first baffle and in said second baffle.   
     
     
         18 . The liquid filled pressure/vacuum valve of  claim 15 , further comprising:
 a test plug port disposed in said inlet.   
     
     
         19 . The liquid filled pressure/vacuum valve of  claim 15 , further comprising:
 a first sensor disposed in said suction zone; and   a second sensor disposed in said pressure zone;   wherein said first sensor and said second sensor are configured to monitor a level of said fluid.   
     
     
         20 . The liquid filled pressure/vacuum valve of  claim 15 , further comprising:
 a fluid fill port and a fluid drain port disposed in said body.   
     
     
         21 . The liquid filled pressure/vacuum valve of  claim 15 , wherein said fluid is a low vapor pressure, hydrophilic, non-foaming liquid. 
     
     
         22 . The liquid filled pressure/vacuum valve of  claim 15 , further comprising:
 at least one flange disposed in said body proximate said separator.   
     
     
         23 . The liquid filled pressure/vacuum valve of  claim 15 , wherein a geometry of said first baffle and said second baffle are configured to achieve a desired operational setting for the liquid filled pressure/vacuum valve of about 6 inches to about 10 inches water column vacuum and about 2.5 inches to about 6 inches water column pressure. 
     
     
         24 . A liquid filled pressure/vacuum valve for underground storage tanks comprising:
 a suction zone having an inlet fluidly coupled to the underground storage tank, said suction zone chamber including said inlet, an upper chamber and a suction zone chamber, said upper chamber is in fluid communication with said suction zone chamber;   a pressure zone having an outlet fluidly coupled to atmosphere and including said outlet, a lower chamber, and a pressure zone chamber, said lower chamber is in fluid communication with said pressure zone chamber, and said pressure zone chamber is in fluid communication with said suction zone chamber; and   a fluid disposed in and configured to flow between said suction zone and said pressure zone, said flow of said fluid is determined by an increased force due to a pressure differential between said suction zone and said pressure zone.   
     
     
         25 . The liquid filled pressure/vacuum valve of  claim 24 , further comprising:
 at least one fluid fill port disposed in said lower chamber; and   at least one fluid drain port disposed in said pressure zone chamber.   
     
     
         26 . The liquid filled pressure/vacuum valve of  claim 24 , wherein said fluid is a low vapor pressure, hydrophilic, non-foaming liquid. 
     
     
         27 . The liquid filled pressure/vacuum valve of  claim 24 , wherein a desired operational setting for the liquid filled pressure/vacuum valve is about 6 inches to about 10 inches water column vacuum and about 2.5 inches to about 6 inches water column pressure. 
     
     
         28 . The liquid filled pressure/vacuum valve of  claim 27 , wherein a desired operational setting for the liquid filled pressure/vacuum valve is about 8 inches to water column vacuum and about 3 inches water column pressure.