Gas chromatograph modular auxiliary oven assembly and method for analyzing a refinery gas

A modular auxiliary oven assembly for use with a gas chromatograph, which oven assembly is comprised of a first housing having at least one inlet fluidly connected to at least one outlet, which housing has contained therein:

• a) an oven which is enclosed in a second housing and containing at least one inlet that is fluidly connected to at least one inlet of the housing and at least one outlet that is fluidly connected to at least one outlet of the housing, which oven has contained therein;
• i) one or more multiport chromatographic sampling valves having inlet ports and outlet ports wherein said sampling valve is capable of receiving a fluid sample in an inlet port and directing it to an outlet port, and wherein one of its inlet ports is fluidly connected to an inlet of said housing;
• ii) one or more fixed volume sampling means that is either an integral part of each one or more sampling valve or is external to the sampling valve;
• iii) one or more chromatograph column or column trains capable of separating chemical components of a chemical sample wherein each column has a first end and a second end, wherein its first end is fluidly connected to an outlet port of a chromatographic sampling valve and its second end is fluidly connected to the outlet of said first enclosed compartment;
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• iv) at least one heater;
• and
• b) an actuating mechanism associated with each sampling valve for switching the sampling valve position for directing the flow of fluid through the sampling valve.