Gas chromatography sample introduction device capable of realizing self cleaning of flow distribution pipeline

Abstract

The invention discloses a gas chromatography sample introduction device capable of realizing self cleaning of a flow distribution pipeline. The gas chromatography sample introduction device comprisesa diverter, a gas chromatograph control unit, a constant temperature heating belt, a temperature controller, a three-way stop valve, a flow distribution pipeline outlet, and a washing gas outlet. According to the gas chromatography sample introduction device, the three-way stop valve is arranged on the flow distribution pipeline of the diverter, the external surfaces of the flow distribution pipeline and the three way stop valve are sleeved with the constant temperature heating belt, the gas chromatograph control unit is used for controlling the three-way stop valve and the constant temperature heating belt respectively, control commands are written on the gas chromatograph control unit, and self cleaning of the flow distribution pipeline is completed. The gas chromatography sample introduction device is capable of ensuring apparatus analysis precision, prolonging apparatus service life, is simple in production technology, is capable of realizing convenient self cleaning, and is low incost.

Description

technical field [0001] The invention relates to a gas chromatographic sampling device in the technical field of analytical instruments, in particular to a gas chromatographic sampling device for self-cleaning split pipes. Background technique [0002] The main difference between the sampling device of the gas chromatograph is that the split port is set or not. Since the gas chromatograph is a high-sensitivity analysis instrument, in addition to directly detecting constant components in the environment, soil, water resources or food, the split mode is also The main application mode is that in the split flow mode, most of the samples flow out from the split flow port. The split flow port of the gas chromatography sampling device in the prior art is at normal temperature. Some components with high boiling points will stay in the pipe of the split port. After staying to a certain extent, the pipe of the split port may be blocked. At the same time, a small amount of components wi...

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Problems solved by technology

[0002] The main difference between the sampling device of the gas chromatograph is that the split port is set or not. Since the gas chromatograph is a high-sensitivity analysis instrument, in addition to directly detecting constant components in the environment, soil, water resources or food, the split mode is also The main application mode is that in the split flow mode, most of the samples flow out from the split flow port. The split flow port of the gas chromatography sampling device in the prior art is at normal temperature. Some components with high boiling points will stay in the pipe of the split port. After staying to a certain extent, the pipe of the split port may be blocked. At the same time, a small amount of components will flow back to the injection port during the sample test, resulting in ghost peaks.

[0003] Once there is a blockage of the split outlet pipe, the instrument maintenance engineer needs to come to repair, remove the split outlet pipe of the gas chromatograph sampling device, and use high-temperature roasting to remove these blockages. However, this maintenance process is not only time-consuming, It costs thousands of dollars in repairs, and if the blockage is too serious, it cannot be completely cleaned, and the residue of stains is inevitable.

In addition, this cleaning is only for the detachable part of the split outlet. The part connected to the injection port cannot be cleaned separately. If it is blocked, the entire gas chromatograph sampling device may need to be replaced. For an imported gas chromatograph sampling device In other words, the price is expensive, and the domestic gas chromatograph sampling device also costs thousands or even tens of thousands of dollars.

In addition, the split end of many gas chromatograph sampling devices is equipped with a gas electronic pressure or flow control module. Pollutants at the split outlet may cause the gas electronic pressure control module to fail to work normally. In severe cases, the gas electronic pressure control module needs to be replaced

For this reason, the cleanliness of the split port of the gas chromatograph sampling device not only directly affects the analysis accuracy, but also affects the service life of the gas chromatograph

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