A method of recovering vapor emitted in a liquid dispensing installation comprising: liquid dispensing means (P.sub.L) adapted to cause said liquid to flow with a liquid flowrate Q.sub.L ; vapor recovery means (P.sub.V) adapted to cause said vapor to flow with a vapor flowrate Q.sub.V along a pipe (120), said vapor flowrate Q.sub.V being controlled by a parameter G. According to the invention, the method includes the following steps: establishing an equation G=F (Q.sub.V, {p.sub.i }) relating the parameter G to the vapor flowrate Q.sub.V and to parameters p.sub.i characteristic of the recovery means and said pipe (120); determining an initial value {p.sub.i }.sub.o of the parameters p.sub.i ; on each dispensing k of liquid: measuring the liquid flowrate Q.sub.Lk and determining a value G.sub.k of the parameter G from the equation: determining a new value {p.sub.i }.sub.k of the parameters p.sub.i to be used for the next dispensing k+1 of liquid. Application to dispensing fuel for motor vehicles.
A gas recirculation system at a filling station is controlled during a refuelling process by generating a corrective control signal used for the next refuelling process, to actuate the gas recirculation system and control the gas volume flow, based on the fuel volume flow signal and the gas volume flow signal as well as optionally further signals.
A system for dispensing liquid hydrocarbons includes a vapour recovery circuit having a vapour/liquid separator and a vapour flow controller. The vapour/liquid separator has a receiving chamber in which liquid is collected and is mounted in the vapour recovery circuit upstream of the vapour flow controller. The recovery chamber is connected to a bleeding pipe having an inlet fitted with a non-return valve.
A fuel dispenser with a booted nozzle for vapor recovery is modified to include check valves in a vapor return path. The check valves selectively allow atmospheric air into the vapor return path to alleviate nuisance shut offs at the nozzle when ORVR vehicle is being fueled. The check valves may be included anywhere in the vapor return path between the nozzle and the vapor recovery vacuum assist pump. The fuel dispenser may further include a pressure sensor in the vapor return line so that the fuel dispenser can determine if the vehicle is an ORVR vehicle or not. If the fuel dispenser determines that an ORVR vehicle is present, the fuel dispenser may modify the operation of the vapor recovery system.
A fuel dispenser with a booted nozzle for vapor recovery is modified to include check valves in a vapor return path. The check valves selectively allow atmospheric air into the vapor return path to alleviate nuisance shut offs at the nozzle when an ORVR vehicle is being fueled. The check valves may be included anywhere in the vapor return path between the nozzle and the vapor recovery vacuum assist pump. The fuel dispenser may further include a pressure sensor in the vapor return line so that the fuel dispenser can determine if the vehicle is an ORVR vehicle or not. If the fuel dispenser determines that an ORVR vehicle is present, the fuel dispenser may modify the operation of the vapor recovery system.
A pressure sensor includes a pair of inputs for determining the pressure within a vapor recovery path. The inputs are positioned about a flow restrictor within the vapor recovery path. The vapor recovery path may include a mounting platform for attaching the pressure sensor and positioning the inputs relative to the flow restrictor. In one embodiment, a vapor sensor may also be positioned within the vapor recovery path. An inlet port and an outlet port direct vapor from the vapor recovery path to a sensor. The inlet and outlet ports are positioned relative to the flow restrictor for forcing the vapor through the sensor. In this embodiment, a common flow restrictor within the vapor recovery path may accommodate both the vapor sensor and the pressure sensor. If vapor is not being returned in the vapor return path properly, the fuel dispenser may set an alarm condition and/or shut down the fuel dispenser operation. If vapor is not being returned at the proper rate, the vapor pump speed may be adjusted, for example, to bring the vapor return rate to the proper level.
