Correct operation method of COD rapid analyzer

The correct operation method of the COD rapid tester The principle of the COD rapid tester is to use an oxidant composed of potassium dichromate and other composite catalysts to heat and digest at a high temperature (165 ° C), and use the single-chip technology for data processing.
Calculate the COD content in the solution
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The COD rapid tester is widely used in environmental monitoring, sewage treatment, scientific research units, colleges and universities and other departments in various industries.
The use of the COD rapid tester should be operated in the correct way: 1.
First, the COD rapid tester should be used before using Turn on the machine and preheat for 30 minutes, and the melter will automatically heat up to 165°C
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2.
The COD rapid analyzer draws 3mL of the sample to be tested, and places it in a cleaned melting tube.
(If the chloride ion content in the sample is too high, add 1mL of mercury sulfate solution
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) Then add 1mL of the corresponding concentration of oxidant and 5mL of Catalyst, shake well
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3.
Insert the melting tube into the melting furnace hole in turn, cover the protective cover, and press the "dissolve" button after the temperature drops below the set value.
Automatic alarm
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 　　4.
Take out the melting tube and put it on the test tube rack.
After natural cooling for two minutes, cool it with water to room temperature
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 　　5.
Draw 3mL of distilled water (blank sample) and put it into a clean melting tube.
(If 1mL of mercury sulfate solution is added as in the previous step, then 1mL of mercury sulfate solution needs to be added, otherwise it will not be added
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) Then add 1mL of the corresponding concentration of oxidant and 5mL catalyst, shake well with stopper
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 　　6.
The COD rapid analyzer adds corresponding distilled water to each melting tube according to the concentration of the water sample (if chlorine-free water samples are measured, add 1 mL of distilled water for the range of 5-100 mg/L, add 3 mL of distilled water for the range of 100-1200 mg/L, and add 3 mL of distilled water for the range of 1000-1000 mg/L).
For 2000mg/L range, add 8mL of distilled water; if chlorine-containing water samples are to be measured, 1mL of mercuric sulfate solution has been added before, then 5~100mg/L range does not need to add distilled water, 100~1200mg/L range adds 2mL of distilled water, 1000~2000mg/L range Add 7mL of distilled water to the L range, shake well with a stopper, and wait for the test
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 　　7.
Press the "Test Blank" button, add the dissolved blank to be tested into the cuvette (fill with two-thirds of the cuvette's volume), and measure its absorbance.
After the absorbance value is stable, press "Confirm" key, the COD rapid analyzer automatically resets to zero, and the instrument displays its absorbance and the COD value of the sample
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 　　8.
Press the "Query Curve" key of the COD rapid analyzer, use the arrow keys to select the desired standard curve serial number, and press the "Enter" key to confirm
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 　　The above is the relevant introduction about the use of the COD rapid tester.
I believe that everyone has a corresponding understanding of it after reading it.
Operating it in the correct way can keep it in good working condition.
I hope it will help you
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