Refrigeration-type purge and trap instrument being applicable to nitric oxide

Abstract

The invention relates to a refrigeration-type purge and trap instrument being applicable to nitric oxide, comprising an inert gas steel cylinder, a mass flow controller, a seawater sample bottle, a gas stripping chamber, an adsorption tube, a trapping device, a control circuit board and a gas circuit formed by connecting a pipeline and an electromagnetic valve. Under the control of the mass flow controller, inert gas in the inert gas steel cylinder is filled into the seawater sample bottle, and water sample in the sample bottle enters into the gas stripping chamber under the action of pressure; the inert gas purges N2O in water body sample from the bottom of the gas stripping chamber, inert gas carrier gas carrying the N2O enters into the adsorption tube from the gas stripping chamber, and moisture and impurity of the carrier gas are absorbed and removed inside the adsorption tube; the carrier gas carrying the N2O then enters into a trapping tube of the trapping device and is used for trapping at the low temperature; after trapping, stop valves at the two ends of the trapping tube are closed, and the N2O is resolved out when the temperature of the trapping tube raises; after resolution, the stop valves at the two ends of the trapping tube are opened, and the carrier gas enters into the trapping tube and brings the N2O into gas chromatogram to be analyzed and detected.

Description

technical field [0001] The invention relates to a purging and trapping device for enriching dissolved gas in water, in particular to a purging and trapping device suitable for low-concentration gas dissolved in water such as nitrous oxide. Background technique [0002] Nitrous oxide (N 2 O) is a nitrogen oxide compound that plays an important role in the global nitrogen cycle. Nitrous oxide (N 2 O) is also one of the main greenhouse gases, which has the longest persistence period (up to 150 years) in the atmosphere among known greenhouse gases. In particular, nitrous oxide (N 2 O) The absorption wavelength of radiation (7.78 μm) is in the main spectral line region (7-14 μm) of atmospheric heat conduction, so it has a significant warming effect. [0003] The ocean is important N 2 O source, analysis and study of N in the ocean 2 The spatiotemporal distribution of O, which is beneficial to reveal the N 2 The generation mechanism and controlling factors of O in the ocean...

AI Technical Summary

Problems solved by technology

However, for N dissolved in water like 2 For samples of trace gases such as O, figure 1 The trapping efficiency of the room temperature trapping purge and trapping device shown cannot meet the detection requirements. A large amount of water vapor is carried out during the purging process, and the enrichment of water vapor into the trapping tube will not only cause damage to the packing in the trapping tube , also reduces the repeatability of the instrument

figure 2 The shown cold trap trap purge and trap device is difficult to realize automatic online continuous operation of the instrument, and the repeatability of the results of the same method between laboratories is not good

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