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Automatic Pressure Correcting Phase II/ORVR Compatible Vapor Recovery System

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Posted / Last update: 01-07-2001
Publication: Petroleum Equipment & Technology Archive
Issued: July 2001
Author: Simpson W. Dwain , PhD

Performance

The SaberVac VR system has been approved by CARB (EO G-70-196) to be over 95% efficient in recovery of vapors generated during vehicle refueling. The results for the 100-car matrix tested are shown in Figure 3. The actual test efficiency average was over 99%. The average measured V/L for the test, which included 92% non-ORVR cars and 8% ORVR cars, was 0.94, and the UST pressure remained slightly less than atmospheric (-0.5" H2O) during the 100-car test, including the effects of all other activity in the test station.

Figure 3:
Synopsis if SaberVac VR 100-Vehicle Test
(CARB TP-201)

During the entire 90-day durability test period before and after the actual 100-vehicle test, the average UST pressure never exceeded +0.2" H2O, as shown in the rolling averages in Figure 4. This 90-day durability test period included the period when winter fuels were dispensed, with Reid Vapor Pressures greater that 11 psi.

Figure 4:
Average UST Pressures of SaberVac VR System

Installation and Maintenance
The SaberVac VR system is probably the easiest VR system to install and maintain. Installing the SaberVac pump itself is no more difficult than installing a hose into the dispenser outlet casting. Once the SaberVac pump is installed, the hose and nozzle components are simply installed onto the pump and installation is complete. With balance-plumbed dispensers, it is not necessary to make any changes in the dispenser or vapor recovery return lines.

Since all components of the system are external to the dispenser itself, replacement of damaged or malfunctioning components is again as simple as replacing a hose or nozzle.

A view of a SaberVac pump installed directly into the dispenser outlet castings is shown in Figure 5. As is seen, not only is the SaberVac easy to install, it essentially blends in with the hose-dispenser interface.

Figure 5:
SaberVac Pumps Installed in Dispenser Outlet Castings

 

A view of the Husky 6051 nozzle (approved with the SaberVac VR system) is shown in Figure 6. The unique features of this nozzle (solid spout, flexible vapor collection bellows, semi-tight seal) make it ideal to use with the SaberVac pump to form a very efficient SaberVac VR vapor recovery system.

Figure 6:
Husky 6051 Nozzle
With Flexible Semi-Tight Seal

 

EVR and ISD
The California Air Resources Board (CARB) has proposed new regulations termed "Enhanced Vapor Recovery (EVR) for control and monitoring of Phase I and Phase II vapor recovery systems. The first phase of these new regulations essentially includes three functions; 1) compatibility with ORVR vehicles, 2) the control of the UST pressures very near atmospheric to eliminate fugitive emissions, and 3) the monitoring of the UST pressures to assure compliance with these levels. The second phase is to expand EVR to include the automatically performing of diagnostics of the system and to report variations and alarm conditions outside acceptable limits. This phase is termed "In Station Diagnostics" (ISD).

The SaberVac VR system has already addressed the "control" functions of EVR with the capability of controlling the UST pressures within the desired limits. As the ORVR population increases, average UST pressures will continue to decrease, insuring, when using SaberVac, that fugitive emissions will be essentially eliminated. The UST monitoring functions, if not already in place, can be added without any modification to the SaberVac VR system itself.

Designs for logic signals appropriate for inclusion in ISD systems are being finalized, and will be incorporated into SaberVac VR systems once approved.

Author
Simpson W. Dwain , PhD
Biography
W. Dwain Simpson, PhD, is President of Synergetic Technologies, Inc. (Wilton, CT) and Saber Technologies, LLC (Fairfield, CT). Dr. Simpson has been active in the development of fuel dispensing and fuel vapor recovery systems since 1989.

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