Coriolis dosing system for filling gas cylinders

A system for sequentially filling one or more target cylinders with a pre-determined quantity of a single gas or liquid component, said system comprising:

• at least one gas source;
• at least one target cylinder for receiving gas from the gas source;
• at least one conduit for distributing gas between the gas source and the target cylinder;
• at least one discrete valve for controlling the flow of gas through the at least one conduit, wherein the discrete valve may only be maintained in an open position or a closed position;
• a controller that is configured to calculate the mass of the pre-determined quantity of the single gas component that is required to be added to the target cylinder to achieve the pre-determined quantity of gas by accounting for an absolute temperature of the gas component, a pressure within the at least one target cylinder, an internal pressure of the at least one conduit, a molar mass of the gas component, a compressibility factor of the gas component rated at the internal pressure of the target cylinder, a compressibility factor of the gas component rated at the internal pressure of the at least one conduit and a volume of at least a portion of the at least one conduit;
• at least one Coriolis mass flow meter that is coupled to the conduit and configured for:
• (i)measuring a mass value of the single gas component flowing through the conduit, and (ii) continuously transmitting instantaneous mass flow rate measurements and cumulative mass flow totals of the single gas component flowing through the mass flow meter;
• and
• at least one flow transmitter configured for;
• (i) receiving the calculated mass from the controller:
• (ii) biasing the discrete valve to an open position to permit the flow of gas through the at least one conduit, (iii) continuously receiving the instantaneous mass flow rate and cumulative mass flow total from the Coriolis mass flow meter, (iv) comparing the calculated mass with the instantaneous mass flow rate and cumulative mass flow total reported by the Coriolis mass flow meter, (v) determining when the target cylinder will receive the calculated mass of gas based upon the comparison step,(vi) biasing the discrete valve to a closed position prior to filling the target cylinder with the calculated mass of gas to compensate for a known latency of the system, and (vii) filling the target cylinder with a quantity of gas that is substantially equal to the calculated mass of gas.