摘要 |
An automated fueling facility allows untrained persons to safely dispense homogenous phase liquid methane from a cryogenic storage tank into a motor vehicle. The fueling facility automatically maintains pressure on the liquid methane within a predetermined safe operating range using methane gas trapped in the cryogenic storage tank. The pressure on the liquid methane is at least set equal to a set pressure equal to the sum of the saturation pressure of the liquid methane plus an additional amount to help to ensure that it remains in a fully saturated condition after absorbing any heat during pumping from the storage tank. A pump is cooled by placing it in the storage tank and circulating liquid methane through the pump and back into the storage tank. A dispenser, including nozzle for connecting to a motor vehicle, is cooled by circulating liquid through the nozzle and back to the storage tank through a receptacle on the dispenser to which the nozzle is connected. No dispensing of liquid methane into a motor vehicle tank is allowed to begin without the pressure of the liquid methane being within the operating range and the pump and nozzle pre-cooled. No additional pressure is built in the storage tank than is necessary to bring the pressure of the liquid methane to the set pressure. |