The following is the debugging and calibration method for high-frequency infrared carbon sulfur analyzer:

Instrument preparation and inspection

-Power and gas source: Open the oxygen cylinder and adjust the pressure to 0.18-0.20MPa to ensure normal and stable oxygen supply. At the same time, check if other gas pipelines are connected correctly and have no leaks.

-Device connection: Open the monitor in order, double-click the infrared carbon sulfur analyzer icon, and analyze the software; Turn on the instrument detection device, ensure normal online connection, high-frequency furnace power switch, electronic balance, printer and other equipment in sequence, and check whether each part is connected properly and whether the equipment can work normally.

-Cleaning and maintenance: Check whether the inside and outside of the instrument are clean, and promptly clean any dust or debris. Especially the combustion tube, metal filter screen and other parts need to be kept clean to avoid affecting the measurement results. If some dark brown particles of the desiccant turn red, they must be replaced, otherwise it will affect the analysis of carbon and sulfur content.

Parameter setting and adjustment

-Analysis software settings: After entering the analysis software, observe that the C and S signals rise until they no longer rise. Click to automatically switch to automatic analysis mode. Before analyzing the sample, input the weight of the sample based on its actual condition, as weight is one of the important parameters for calculating carbon and sulfur content.

-Gas flow rate setting: Set the oxygen carrying flow rate to 0.08MPa, the top oxygen flow rate to 1.2-1.5L/min, and analyze the gas flow rate to be around 3.5L/min. These gas flow parameters are crucial for ensuring sufficient combustion and accurate analysis of the sample, and need to be fine tuned according to the actual situation.

Calibration operation

-Zero point calibration: Before starting the formal analysis, zero point calibration is required. Usually, zero point calibration is performed using standard substances such as pure iron that do not contain carbon or sulfur or have extremely low carbon and sulfur content, in order to eliminate the influence of the instrument's background values on the measurement results.

-Calibration of standard substances: Select standard substances with similar composition and known carbon and sulfur content to the sample to be tested for calibration. Place the standard substance in a high-frequency furnace for analysis, and the instrument will automatically calculate the calibration coefficient based on the known carbon and sulfur content of the standard substance, and correct the subsequent measurement results. It is generally recommended to use at least two standard substances with different carbon and sulfur contents for calibration to improve the accuracy and reliability of the calibration.

-Linear calibration: By analyzing a series of standard substances with different carbon and sulfur contents, establish a linear relationship between carbon and sulfur content and instrument measurement signals. In practical operation, multiple concentration gradient standard substances can be selected for analysis from low to high, and then a calibration curve between carbon and sulfur content and measurement signal can be drawn based on the measurement results. If the linearity of the calibration curve is good, it indicates that the instrument has good linearity; If the linear deviation is large, further inspection of the instrument's performance or adjustment of relevant parameters is required.

Performance validation and optimization

-Repeatability test: Conduct multiple repeated analyses using the same standard substance to check the repeatability of the measurement results. Generally speaking, the repeatability of carbon content should be ≤ 0.8%, and the repeatability of sulfur content should be ≤ 3.0%. If the repeatability does not meet the requirements, it is necessary to check the stability of the instrument, the stability of the gas flow rate, and the consistency of the operation process.

-Accuracy verification: Verify the accuracy of the instrument using other reliable analytical methods or higher-level standard substances. If there is a deviation in the measurement results, further analysis of the reasons may be due to inaccurate calibration, instrument failure, insufficient reagent purity, and other factors, and then targeted correction and optimization should be carried out.