Gas Chromatograph Injector Carrier Gas Conservation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Traditional gas chromatography systems consume large volumes of carrier gas, particularly helium, due to high split and septum purge flows, leading to inefficient use and potential contamination issues, which is exacerbated by the increasing cost and scarcity of helium.
Innovation Solution
A device and method for a gas chromatograph system that includes an injector, conduit assembly, flow restrictor, and pressure controller, which supplies carrier gas at a constant pressure and uses an auxiliary gas to manage flow during injection and separation phases, preventing auxiliary gas from entering the analytical column during separation, thereby conserving carrier gas and reducing contamination.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If large split flow is used to reduce contaminants through dilution, then contamination is reduced, but carrier gas consumption increases
Solution Approach 1:
The patent extracts the contaminant removal function from the carrier gas flow path by introducing a separate auxiliary gas (nitrogen or argon) that is dedicated to purging contaminants through the split vent and septum purge vent, allowing the carrier gas to be used solely for analytical separation without being wasted on dilution purposes
Solution Approach 2:
The gas flow system is segmented into two independent streams: carrier gas (helium) for analytical column flow and auxiliary gas (nitrogen/argon) for split and purge flows. This segmentation allows each gas type to be optimized for its specific function, preventing carrier gas consumption in non-analytical paths
2Measurement precision
If high purity helium is used as carrier gas, then sensitivity and efficiency are improved, but cost and procurement difficulty increase
Solution Approach 1:
The patent changes the gas composition parameter by replacing helium in the split and purge flows with alternative gases (nitrogen or argon), while maintaining helium exclusively in the analytical column path where it provides the necessary sensitivity and efficiency benefits
Solution Approach 2:
Different gas qualities are applied to different parts of the system: high purity helium is used locally in the analytical column path where sensitivity is critical, while cheaper alternative gases are used in the split and purge paths where sensitivity requirements are less stringent
3Ease of operation
If multiple connections and valves are used in the flow path, then flow control is improved, but outgassing of contaminants increases
Solution Approach 1:
The patent introduces an intermediary auxiliary gas system that handles the contaminant-prone functions (split vent, septum purge) separately from the main carrier gas path, reducing the need for multiple valves and connections in the high purity carrier gas flow path
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
Significantly reduces carrier gas consumption, maintains data quality by minimizing contamination, and allows for the use of alternative gases like nitrogen or argon as auxiliary gases, thereby extending the life of helium supplies and reducing operational costs.
Implementation Method 1
A carrier gas can be supplied to the injector from the carrier gas source at a constant pressure through a flow restrictor
Implementation Method 2
The pressure controller can be configured to control the pressure of an auxiliary gas supplied to the injector from the auxiliary source
Implementation Method 3
Traditional split/splitless (SSL) or programmed temperature vaporizing (PTV) injection ports for gas chromatographs
Data Source
AI summary
A device for a gas chromatograph system includes an injector, a conduit assembly, a flow restrictor, and a pressure controller. The injector is connected to a carrier gas source and an auxiliary gas source. The conduit assembly surrounds the input end of an analytical column. A carrier gas is supplied at a constant pressure through a flow restrictor to the injector. A pressure controller is configured to control the pressure of an auxiliary gas supplied to the injector from the auxiliary source. The pressure controller is configured to operate in a first mode 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 to operate in a second mode to provide a second auxiliary gas pressure below a threshold necessary to flow auxiliary gas into the analytical column during a resolving phase.