Systems and Methods for Conserving Carrier Gas

A gas chromatograph system comprising:

• an analytical column;
• a detector coupled to an output end of the analytical column;
• an injector connected to a carrier gas source and an auxiliary gas source;
• a conduit assembly surrounding the input end of an analytical column;
• a flow restrictor through which a carrier gas is supplied to the injector from the carrier gas source at a substantially constant pressure;
• and
• a pressure controller configured to control the pressure of an auxiliary gas supplied to the injector from the auxiliary source, the pressure controller configured to provide a first auxiliary gas pressure sufficient to force a flow of the auxiliary gas and a sample onto the analytical column during an inject phase and a second auxiliary gas pressure below a threshold necessary to flow auxiliary gas into the analytical column during a resolving phase.

A method for supplying a carrier gas to a gas chromatograph, comprising:

• providing a carrier gas flow and an auxiliary gas flow to an injector, the carrier gas flow being at a substantially fixed pressure and passing through a flow restrictor;
• changing an auxiliary gas pressure during an inject phase to a first pressure sufficient to force at least a portion of the auxiliary gas flow and at least a portion of a sample onto an analytical column;
• changing an auxiliary gas pressure during an resolving phase to an operating pressure of the analytical column;
• resolving at least two compounds of the sample with the analytical column;
• and
• detecting the at least two compounds exiting the analytical column.