High-precision calibration method and device for optical dissolved oxygen sensor

Abstract

The invention relates to the technical field of water dissolved gas sensor calibration, and aims at providing a high-precision optical dissolved oxygen sensor calibration method and device. The high-precision optical dissolved oxygen sensor calibration method comprises the following steps: sequentially introducing mixed gases with different oxygen contents into a water-gas mixer, so as to supply multiple dissolved oxygen concentration gradients to a water body; recording a signal value of a dissolved oxygen sensor to be calibrated and a temperature value of the water body, and testing a standard dissolved oxygen value of a water sample by using an iodometric method; calculating a calibration coefficient of the dissolved oxygen sensor to be calibrated. As a practical iodometric method measured value obtained after synchronous sampling is taken as the standard value, the reference value precision of the method is greatly improved when being compared with conventional methods that the concentration of dissolved oxygen in water bodies is calculated according to the water dissolution degree of the mixed gas oxygen concentration; as five temperatures are adopted for sensor calibration, the calibration result is relatively wide in temperature application range when being compared with those of the conventional methods.

Description

technical field [0001] The invention relates to the technical field of calibrating dissolved gas sensors in water, in particular to a high-precision calibrating method and device for an optical dissolved oxygen sensor. Background technique [0002] Dissolved oxygen in water has a vital impact on the survival of aquatic organisms, and it is of great significance to quickly and accurately determine the content of dissolved oxygen in water. In recent years, with the advancement of science and technology, the technology of in situ sensor measurement of dissolved oxygen has developed rapidly. The optical dissolved oxygen sensor based on the principle of fluorescence quenching has high stability and can realize undisturbed long-term continuous in-situ monitoring that cannot be accomplished by traditional methods. It has greatly improved the measurement method of dissolved oxygen in rivers, lakes, oceans and other water bodies. It has been widely used in fisheries, mining, marine ...

AI Technical Summary

Problems solved by technology

[0005] The technical problem to be solved by the present invention is to overcome the shortcomings of existing dissolved oxygen sensor calibration methods such as few calibration points, inaccurate standard values, and limited application range of calibration results, and provide a calibration method based on temperature and dissolved oxygen control devices, so that calibration The final sensor results can be highly consistent with the standard value in a large range of dissolved oxygen concentration and ambient temperature

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