• ARID’s PERMEATOR System Earns CARB Certification...
• PERMEATOR Systems to be Installed at ALL H-E-B Houston area sites...
• ARID Receives Certification from Maryland...
• Independent 3rd Party Field Testing Confirms...
• Texas ORVR Certification Approval...
• ARID Announces Completion of Study...
• ARID announces appointment...
• Vapor Recovery Around the World
• Retooling the Vapor Recovery System
• Membranes, Molecules and the Science of Permeation

Page 6

5.0 Calculations

The outlet hydrocarbon (HC) mass is calculated from the measured outlet volume corrected to standard conditions, the outlet HC concentration as propane and the density of propane. Standard conditions are 68 degrees F and 29.92 inches Hg.

The outlet volume during any one minute test interval is corrected to standard conditions using the formula:

Where:
17.65 = Standard Temperature / Standard Pressure
V_acf = Recorded meter volume in cubic feet
P_A = Absolute pressure (barometric plus turbine meter) in inches of mercury
T = Temperature in volume meter in °F

The mass of hydrocarbons emitted from the outlet during any one minute test period is calculated from:

Where:
HC_(out) = Hydrocarbon concentration at the outlet in %C₃
Note: The density of propane is 51,950 mg/ft³

For recovery efficiency of the PERMEATOR®, the feed volume is calculated from the outlet volume, outlet hydrocarbon concentration, permeate hydrocarbon concentration and inlet hydrocarbon concentration.

Where:
HC_(in) = Hydrocarbon concentration at the inlet in %C₃ HC_(P) = Hydrocarbon concentration at the permeate in %C₃

The inlet mass during any one minute test interval is: