Gas online analysis device based on optical integrating sphere

Abstract

The invention provides a gas online analysis device based on an optical integrating sphere. The device mainly comprises a sampling unit, a pre-processing unit and an integrating sphere measuring unit, wherein an integrating sphere of the integrating sphere measuring unit mainly comprises a transparent substrate, a diffuse reflection layer, diaphragms and air ports; the outer side of a spherical cavity formed by the transparent substrate is coated with the diffuse reflection layer; an incident light path and an emergent light path intersect in a coplanar manner; incident light in the integrating sphere is reflected by the diffuse reflection layer multiple times and acts with a sample to generate a characteristic spectrum inside the integrating sphere; and the generated characteristic spectrum is superposed on the emergent diaphragm and is effectively received after being reflected by the diffuse reflection layer multiple times. The gas online analysis device has the effects that measuring errors caused by changes of light shapes and divergence angles can be also effectively inhibited by utilizing the integrating sphere; and under the condition of equivalent line diameters, the sensitivity and stability of traditional cylindrical gas chambers can be improved by 3-10 times.

Description

technical field [0001] The invention relates to an online gas analysis device, which is applicable to the methods based on "spectrophotometry" (including differential absorption spectroscopy, non-dispersive infrared absorption spectroscopy), "fluorescence photometry", "chemiluminescence" and "Raman spectroscopy". " and other gas online monitoring instruments, especially suitable for the field of gas online monitoring with very strict requirements on "sensitivity" and "detection limit". Background technique [0002] Conventional gas on-line monitoring instruments based on "photometry" (including differential absorption spectroscopy and non-dispersive infrared absorption spectroscopy) mostly use cylindrical gas chambers for their sample chambers. limited, resulting in low sensitivity and high detection limit; ②Only the gas sample in the light-passing part reacts with light, resulting in no obvious difference in the reaction of gas samples with different concentrations, which u...

AI Technical Summary

Problems solved by technology

[0002] Conventional gas on-line monitoring instruments based on "photometry" (including differential absorption spectroscopy and non-dispersive infrared absorption spectroscopy) mostly use cylindrical gas chambers for their sample chambers. limited, resulting in low sensitivity and high detection limit; ②Only the gas sample in the light-passing part reacts with light, resulting in no obvious difference in the reaction of gas samples with different concentrations, which ultimately leads to the detection limit and sensitivity being affected. limit

Although these two methods can increase the optical distance, the distance between the "light source" and the "light receiving end" is also extended, resulting in a small change in the position of the light source or any end of the light receiving end, and a small change in the shape of the light. Small changes in the divergence angle and divergence angle will cause large light measurement errors, which will affect the stability (or repeatability) of the measurement, resulting in limited improvement in its sensitivity and detection limit.

[0004] In addition, the above two methods cannot allow all samples to interact with light, and cannot increase the degree of difference in the reaction of samples with different concentrations of gas, so the degree of improvement in sensitivity, detection limit and data stability is very limited.

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