Precautions for the use of COD water quality analyzer

The COD water quality analyzer is based on the national certification method HJ/T399-2007 'Determination of Water Chemical Oxygen Demand Rapid Digestion Spectrophotometry', which can quickly determine the concentration of COD in enterprise wastewater, using colorimetric measurement, an advanced cold light source. Narrow-band interference technology and microcomputer automatically process data and directly display and print the concentration value of the sample. The device is equipped with a 4.3-inch full-color LCD screen and a guided detection mode, which reduces learning costs and allows users to operate easily and quickly.

Detection principle:

A known amount of potassium dichromate solution was added to the sample, and in a strong sulfuric acid medium, silver sulfate was used as a catalyst, and after high-temperature digestion, the absorbance of cod at a specific light source wavelength was measured. The imported cold light source emits the light source signal to the sensor, and the data is processed by the ARM processor, and the sample concentration value is directly fed back, which is displayed in units of mg/L.

Application areas:

It can be widely used in scientific research institutes, sewage engineering, water environment testing, petrochemical industry, metallurgy steel, biomedicine, food and dairy industry, wool textile printing and dyeing, electronic machinery, aquaculture, photovoltaic, leather, paper making, etc.

Instrument features:

1. The measuring instrument is separated from the digestion instrument, which does not affect the stability of the optical system.

2. The measuring instrument is a cold light source and a narrow-band interference optical system with good optical stability.

3. The color of the cuvettes is better in linearity.

4. LCD large-screen LCD display in Chinese, is easy to operate and intuitive.

5. The temperature of the digestion apparatus is automatically controlled by PID. Timing, high precision.

6. The operation is simple and time-saving, and there is no need to change the tube for digestion and colorimetry.

7. The digestion temperature and time can be set for other purposes.

8. It can save 10 standard curves and 500 measured values and will not be lost after power failure.

Precautions for the use of COD water quality analyzer:

1. Daily inspection: It mainly includes checking whether the instrument is working normally, such as whether the inlet and outlet pipelines are unobstructed, whether there is leakage, keeping the instrument clean, especially the rotating parts and vulnerable parts should be regularly inspected and replaced to prevent damage caused by leakage of the instrument and corrosion.

2. Replacement of reagents: Potassium dichromate and sulfuric acid are strong silver preservatives and absorb moisture and volatilize on the work site, and should be replaced regularly. Depending on the replacement cycle used, usually at least every 3 months.

3. Protective maintenance: The peristaltic pump tube absorbs strong corrosive reagents and is replaced every 3 months. The metering and reaction chambers should be thoroughly inspected and cleaned at least once a year.

4. Daily calibration: In addition to the automatic zero cycle calibration set by the program, the zero and standard solution calibration should be performed after the second use, reagent replacement, or protection maintenance. A distilled water prepared in the laboratory is used as the calibration solution. The calibration process is the same as the measurement cycle process. After calibration, the parameters of the new zero point are retained and the working curve is calibrated.

5. Factory parameters: Although the original working curve of the instrument has been established when it leaves the factory, due to the different places of use, the original working curve cannot meet any monitoring situation and should be checked regularly. The cod standard solution can be calibrated by the laboratory. The calibration procedure is the same as the measurement cycle procedure. After calibration, the interface parameters can be changed to calibrate the working curve.

6. Installation environment: In order to ensure the constant temperature and humidity at the installation site of the chemical oxygen demand online tester, if necessary, air conditioners and other heating, cooling and dehumidification facilities should be installed. At the same time, an independent stable power supply is used.

7. Instrument Pause: After the suspension of the instrument is rinsed thoroughly with distilled water and drained, then click to close the inlet and outlet valves and power, re-enable with new reagents thoroughly cleaned, and work curve calibration.