What should be paid attention to in the use of multi-parameter water quality analyzer?

Chemical Oxygen Demand COD. is the amount of oxidant consumed by the treatment of water samples with strong oxidants under certain conditions. The presence of water is a reducing substance. The reducing substances are mainly organic substances. Chemical oxygen demand COD. is a comprehensive indicator to measure the degree of organic pollution in water bodies, and it is also an important content in environmental monitoring. The basic principle is to prepare a series of standard samples with the standard substance sodium hydrogen phthalate. The standard samples of known concentration are digested with human digestive juice to obtain the oxygen consumption of each standard sample. In the COD absorbance coordinate system instrument method, the standard curve is drawn using the small square multiplication method. After measuring the absorbance of the water sample with unknown concentration to be measured, the COD value can be obtained from the standard curve. Precautions for the use of multi-parameter water quality analyzer:

1. Daily inspection includes checking whether the instrument is working normally, whether the pipeline is unobstructed and leaking, and cleaning the instrument, especially the rotating parts and vulnerable parts, to prevent leakage, corrosion, and damage to the instrument.

2. Reagent replacement Potassium dichromate and silver sulfate are very corrosive reagents, which are volatile and absorb water at the worksite and should be replaced regularly. The replacement period depends on the conditions of use, generally at least 3 months.

3. Protective maintenance As the peristaltic pump tube absorbs strong corrosives, it should be replaced every 3 months. The measuring room and reaction room shall be thoroughly inspected and overhauled at least once a year.

4. Daily calibration

Except when the automatic zero calibration period is programmed, in use, replace the reagent or protect and repair the zero standard solution to be calibrated. Using distilled water as the zero point calibration laboratory fluid, the same method in the calibration measurement cycle, the new calibration zero retention parameters, and the calibration curve are prepared.

5. Factory parameter setting

Although the original working curve has been set when the instrument leaves the factory, the original working curve is often not suitable for any monitoring occasions due to the difference in the use place. The working curve should be checked regularly.. COD prepared in the laboratory. The standard solution can be checked, and the calibration process is the same as the measurement cycle. After checking, the interface parameters can be changed and the working curve can be calibrated.

6. Installation environment

In order to ensure that the COD online analyzer is installed at a constant humidity temperature, it is necessary to install an air conditioner, if necessary, heating, cooling, and dehumidification facilities. When using an independent power supply.

7. Instrument pause

When the instrument is out of service, it should be thoroughly cleaned with distilled water first, then drained, and then the inlet and outlet valves and power supply should be closed in turn. When restarting, it should be thoroughly cleaned with new reagents. The working curve should be more accurate.