FUELING SYSTEM VAPOR RECOVERY AND CONTAINMENT PERFORMANCE MONITOR AND METHOD OF OPERATION THEREOF

• US 20130091931A1
• Filed: 12/06/2012
• Published: 04/18/2013
• Est. Priority Date: 11/30/1999
• Status: Active Grant

• Current Assignee: Veeder-Root Co (Vontier Corp.)
• Original Assignee: Veeder-Root Co (Vontier Corp.)
• Inventors: Hart, Robert P.
• Granted Patent: US 8,893,542 B2
• Time in Patent Office: Days
• US Class Current: 73/40
• CPC Class Codes: B67D 7/0486 Pumps driven in response to electric signals indicative of pressure, temperature or liquid flow
• CPC Class Codes: B67D 7/0496 Performance test devices therefor
• CPC Class Codes: F02M 25/0809 Judging failure of purge control system
• CPC Class Codes: F02M 25/0872 Details of the fuel vapour pipes or conduits
• CPC Class Codes: G01M 3/02 by using fluid or vacuum
• CPC Class Codes: G01M 3/26 by measuring rate of loss or gain of fluid, e.g. by pressure-responsive devices, by flow detectors

Abstract

A method and apparatus for monitoring and determining fuel vapor recovery performance is disclosed. The dispensing of liquid fuel into a tank by a conventional gas pump nozzle naturally displaces a mixture of air and fuel ullage vapor in the tank. These displaced vapors may be recovered at the dispensing point nozzle by a vapor recovery system. A properly functioning vapor recovery system recovers approximately one unit volume of vapor for every unit volume of dispensed liquid fuel. The ratio of recovered vapor to dispensed fuel is termed the A/L ratio, which should ideally be approximately equal to one (1). The A/L ratio, and thus the proper functioning of the vapor recovery system, may be determined by measuring liquid fuel flow and return vapor flow (using a vapor flow sensor) on a nozzle-by-nozzle basis. The disclosed methods and apparatus provide for the determination of A/L ratios for individual nozzles using a reduced number of vapor flow sensors. The disclosed methods and apparatus also provide for the determination of fuel dispensing system vapor containment integrity, and the differentiation of true vapor recovery failures as opposed to false failures resulting from the refueling of vehicles provided with onboard vapor recovery systems.

Claims

1. A system for monitoring vapor containment in a liquid fuel dispensing facility having a fuel storage system that provides fuel for dispensing by at least one fuel dispensing unit, comprising:

a pressure sensor operatively connected to the fuel storage system to measure the pressure in the fuel storage system; and

a monitor operatively connected to the pressure sensor wherein the monitor is adapted to;

detect if all of the at least one fuel dispensing units are idle, and if all of the at least one fuel dispensing units are idle;

monitor a pressure level in the fuel storage system over a period of time to determine if the fuel storage system contains a leak; and

abort the monitoring of the pressure level in the fuel storage system at any time that any of the at least one fuel dispensing units are not idle before the period of time expires.

2. The system of claim 1, wherein the pressure sensor is located in a location comprised from the group consisting of a fuel storage tank, a fuel storage tank vapor space, a fuel storage tank vent pipe, a pipeline system, and a common vapor return pipeline.

3. The system of claim 1, wherein the monitor detects if the fuel storage system is adequately tight by monitoring the decay of the pressure level over the period of time.

4. The system of claim 3, wherein the monitor detects if the decay of the pressure level over the period of time exceeds a threshold level.

5. The system of claim 4, wherein the monitor indicates a fail condition if the decay of the pressure level over the period of time exceeds the threshold level.

6. The system of claim 4, wherein the monitor indicates a pass condition if the decay of the pressure level over the period of time does not exceed the threshold level.

7. The system of claim 1, further comprising a tank gauge that is communicatively coupled to the monitor, wherein the tank gauge provides the liquid fuel levels of the fuel storage system to the monitor.

8. The system of claim 1, wherein the monitor is further adapted to receive start and stop events communicated to the at least one fuel dispensing unit to detect if all of the at least one fuel dispensing units are idle.

9. The system of claim 8, wherein the monitor is coupled to either a meter in the at least one fuel dispensing unit, a dispenser controller coupled to the at least one fuel dispensing unit, or a dispenser current loop wiring coupled to the at least one fuel dispensing unit to receive the start and stop events.

10. The system of claim 1, wherein the monitor reports the pressure level to a dispenser controller which is communicatively coupled to the at least one fuel dispensing unit.