Is there a large discrepancy between the readings from an online COD monitor and those obtained using the potassium permanganate method?
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The value read by the online COD monitor is always 50 mg/L, but when we use the potassium permanganate method to measure COD, the value is around 100. Could you please help explain this? Thank you!
Sorry, I made a typing mistake; it’s the potassium dichromate method
Which COD online monitoring instrument are you using?
This exists objectively. Generally, that’s how it is. It makes sense that the instrument calculates based on the light transmittance of the substance produced. The Environmental Protection Agency also approves it. Especially when preparing standard samples, the accuracy of manual methods simply cannot compare to that of instruments.