Alkaline nitrogen analyzerIt is widely used in many industries such as petroleum and chemical, and its accurate calibration is related to the reliability of detection results and the reasonable control of subsequent production processes. Therefore, there are strict calibration standards.

1、 Preparation before calibration

Firstly, it is necessary to ensure that the measuring instrument is under normal working conditions and avoid external factors such as temperature and humidity from interfering with calibration. Generally, it is required that the ambient temperature be maintained within a relatively stable range and the humidity be controlled within an appropriate range. At the same time, it is necessary to prepare the standard substances required for calibration. The purity, concentration, and other indicators of these standard substances must be accurate and reliable, and must comply with the corresponding national standards or industry specifications, such as using certified standard alkaline nitrogen solutions. In addition, it is necessary to thoroughly clean the measuring instrument to ensure that there are no residual impurities, oil stains, etc. inside the instrument, injection system, reaction vessel, and other components, so as not to affect the accuracy of calibration.

2、 Specific operational steps for calibration

In operation, zero calibration should be performed first. Inject blank samples (such as pure solvents) according to the normal injection process of the measuring instrument, and adjust the response value of the instrument to the zero position through the instrument's zero adjustment function. This step aims to eliminate the background signal of the instrument itself when there is no alkaline nitrogen input, ensuring the accuracy of subsequent measurements.

Next, perform range calibration by sequentially injecting standard alkaline nitrogen solutions with different concentration gradients for testing. Starting from a low concentration, gradually increase the concentration and record the correspondence between the measured value displayed by the instrument and the actual concentration of the standard solution. For example, select several representative concentration points, such as low concentration 10mg/L, medium concentration 50mg/L, and high concentration 100mg/L standard solutions, inject them into the measuring instrument, compare the measurement results given by the instrument with the known concentration, and adjust the range of the instrument according to the calibration program or relevant calculation formula provided by the instrument, so that the measurement error of the instrument is controlled within the allowable range throughout the entire range, usually requiring an error not exceeding a certain percentage, such as ± 5%.

3、 Verification and recording after calibration

After completing the calibration operation, verification work is still required. Re select standard solutions of different concentrations for testing to check if the instrument can output measurement results stably and accurately. If there are any situations beyond the error range, it is necessary to re-examine the calibration process, identify the cause, and perform calibration again.

At the same time, a detailed record of the entire calibration process should be kept, including the calibration time, information on the standard substances used, specific data for zero point calibration and range calibration, and verification status. These records can not only serve as evidence for this calibration work, but also help to trace the use of the instrument in the future and analyze the causes when problems arise, providing reference for regular maintenance and recalibration of the instrument.

In short, strict adherence to the calibration specifications of alkaline nitrogen analyzers is necessary to ensure their accurate and reliable detection function in practical applications, providing strong data support for production and quality control in related industries.