HOW TO CHOOSE A URV (Vapor Recovery Unit)
BY CONDENSATION FOR A GAS STATION ?
In a service station equipped with safety valves on the vents(1), the only losses of gasoline vapors occur during the filling of underground tanks.
Except during the filling of underground tanks by tanker truck, there is no justification for the operation of condensation equipment because the pressures are almost nonexistent even for stations with stage 2 recovery system.
Given these factual and universal findings, the use of a condensation VRU should only occur during unloading by the tanker truck.
For this, a minimum cooling capacity is essential; it depends on the temperature of the vapors, on the ambient temperature, and, of course, particularly on the discharge rates.
This is why an URV vapor recovery unit by condensation must be designed with sufficient cooling capacity to treat high flow rates (45 to 50 m3/h).
The universal laws of physics make that this power must be 10 KW to maximize the recovery by condensation at -35 or -40 ° C with the high flow rate of the delivery by the tanker truck.
Equipment that operates outside unloading by the tanker truck, causes unnecessary energy expenditure; it is not powerful enough to properly condense the large flow of vapors during unloading.
(1) The first cause of vapor emission is naturally through the tank vent if this vent is not equipped with a calibrated valve; this equipment, which is very inexpensive and easy to install, prevents normal vapors from escaping into the atmosphere.