1406627 Liquid dispensing apparatus VAPOREX 24 Oct 1972 [12 June 1972] 48851/72 Heading T In a method and system for handling the vapour of a volatile liquid, e.g. petrol, at a dispensing station petrol in underground tanks 18 is pumped via lines 16 to island dispensers 14 and then via one line in a double hose to vehicle tanks, the vapour displaced from the tanks passing via the other line and lines 22 back to a tank 18. The vapour in the tanks is then circulated via lines 30, 32 through a cooling chamber 26 cooled by a refrigerator 36 whereby the difference in pressure between the tanks and the chamber maintains the circulation, possibly aided by pumps. The vapour in the chamber condenses and condensed liquid and dense cooled vapour gravitates back to the central tank 18 via vapour and condensate standpipes 44, 46. To prevent escape of vapour to the atmosphere, the maximum vapour pressure must not exceed the order of 2 ounces per square inch, and pressure switch 40 actuates the refrigerator at or below this pressure while, should the vapour handling system fail, relief valve 54 vents vapour at a pre-set level, e.g. 11b per square inch pressure. Tanker 55 fills the tanks 18 via lines, 56, 60 and returns excess vapour via lines 62, 66 to the tanker. If the tanks are above ground, they are provided with vapour pressure controlled heaters to prevent "breathing" due to changes in atmospheric temperature.
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