Vapor space pressure control system for underground gasoline storage tank
AssigneeHealy Systems, Inc.
InventorJames W. Healy
Life of this patent
Estimating the term…
Abstract
A passive pressure control method and system for controlling pressure in the ullage vapor space of a volatile liquid fuel underground storage tank (“UST”) temporarily, during periods of increasing ullage vapor space pressure, allows vapor to flow into an auxiliary vapor space of variable volume, defined at least in part by a resilient wall member, thereby to reduce the volume of vapor otherwise released to the environment.
Claims27
A passive pressure control method for controlling pressure in ullage vapor space of a volatile liquid fuel underground storage tank (“UST”) comprising the steps of:
- removing liquid fuel from the UST, including for delivery into a vehicle fuel tank,
- delivering into the ullage vapor space of the UST, to replace the volume of liquid fuel removed, a gaseous flow comprising at least one of:
- (a) fuel vapor and air, e.g. displaced from the fuel tank by delivery of the liquid fuel;
- and
- (b) air;
- and,
- during periods of increasing ullage vapor space pressure, allowing vapor to flow from the ullage vapor space into an auxiliary vapor space of variable volume defined at least in part by a resilient wall member, the flow of vapor into the auxiliary vapor space causing deflection of the resilient wall member, thereby increasing the combined vapor storage volume of the ullage vapor space and the auxiliary vapor space.
A passive pressure control system for controlling pressure in the ullage vapor space of a volatile liquid fuel underground storage tank (“UST”) comprising means for temporarily, during periods of increasing ullage vapor space pressure, allowing vapor to flow from the ullage vapor space into an auxiliary vapor space of variable volume, defined at least in part by a resilient wall member.
A passive pressure control system for controlling pressure in the ullage vapor space of a volatile liquid fuel underground storage tank (“UST”) comprising:
- an underground storage tank defining a storage volume for storage of volatile liquid fuel with an ullage vapor space,
- an auxiliary tank defining an auxiliary vapor space in communication with the ullage vapor space, the auxiliary vapor space defined at least in part by a resilient wall member,
- said resilient wall member adapted to deflect from an at-rest position in response to increasing vapor pressure in the auxiliary vapor space, thereby to increase the contained effective vapor storage volume of the auxiliary vapor space, and
- said resilient wall adapted to return toward the at-rest position in response to decreasing vapor pressure in the auxiliary vapor space, thereby to decrease the contained effective vapor storage volume of the auxiliary vapor space.
A passive pressure control system for controlling pressure in the ullage vapor space of a volatile liquid fuel underground storage tank (“UST”) comprising means for temporarily, during periods of increasing ullage vapor space pressure, allowing vapor to flow from the ullage vapor flow into an auxiliary vapor space of variable volume.
Dependencies are inferred from the claim text.