06174351 is referenced by 15 patents and cites 20 patents.

A vapor recovery and pressure management system for a vehicle refueling facility includes two rotary vane pumps and a hydrocarbon-stripping membrane between the pumps. One pump draws vapor from a storage tank as well as from refueling nozzles, while the other pump draws vapor from the membrane and discharges the vapor back into the tank. A controller controls both pumps to maintain a slight vacuum in the tank, thereby preventing leakage of hydrocarbons from the tank to the atmosphere. Clean air from the membrane is exhausted, preferably through a charcoal canister, and a hydrocarbon sensor monitors for the presence of undesirable hydrocarbons in the clean air exhaust. One or more liquid drop outs are provided for separating liquid from the hydrocarbon vapor and returning the liquid to the tank along with the vapor, preferably before the liquid is sent to the membrane, to thereby increase efficient fuel recovery and to protect the membrane from undesirable contact with liquid.

Title
Pressure management and vapor recovery system for filling stations
Application Number
9/277334
Publication Number
6174351 (B1)
Application Date
March 26, 1999
Publication Date
January 16, 2001
Inventor
John M Gray
San Marcos
CA, US
Robert W McDowell
San Diego
CA, US
Agent
Dinsmore & Shohl
US
Assignee
Delaware Capital Formation
DE, US
IPC
B01D 53/22
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