Analysis issues with HACH-DR3900COD
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There is a HACH-DR3900 in the workshop used to measure COD in distillation wastewater. Question 1: After sampling and heating, should it be allowed to cool naturally to a certain temperature before reading, or can it be cooled artificially? Question two: Should the dilution factor on the panel be turned on? What value is appropriate to set? I ask for guidance from the experienced experts!
Under normal circumstances, when there’s nothing to do, just leave it there to cool down naturally; you can do other things in the meantime. Logically, forced cooling shouldn’t be a big problem (to prevent freezing), as the solution after digestion is still quite stable. I don’t think it’s necessary; cooling doesn’t take much time. That dilution factor should be calculated, that is, how many times your sample has been diluted, and the result is read directly from that. It can be verified.
This post was last edited by sunshineda_VGMP on 2018-8-8 16:02. Chemical oxygen demand is an important parameter in the management and research of domestic sewage, wastewater from treatment plants, polluted water bodies, and industrial wastewater. The original method has a long digestion time, and its disadvantages are particularly evident when processing large numbers of samples. It can be heated and decomposed using a COD digester, but it needs to be cooled naturally to room temperature before further analysis is carried out using a multi-functional water quality tester.