The issue of COD values in wastewater
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Given the concentrations of phenol, ammonia, and oil in wastewater, can its COD value be calculated using a formula? What is the formula again?
The concentration of pollutants in wastewater is generally determined through measurement, rather than calculation. COD is determined by the chromate method
The concentration of pollutants in wastewater is generally determined through measurement, rather than calculation. COD is determined by the chromate method
No highly accurate calculation data is needed; I heard that there is a rough correspondence with those substances in water.
The calculation of oxygen demand is generally done through measurement; there are established empirical values for this purpose.
Phenol: COD: 2.33~2.38 g/g; BOD: 1.1~2.0 g/g; Toxicity: 64 mg/L; The oil is a mixture, so it is impossible to calculate； Ammonia nitrogen is an inorganic substance and has no effect on COD.
Phenol can be considered as CxHyOz + O2 → H2O + CO2; the equation can be balanced by adjusting the coefficients. However, the COD value calculated using this theory is higher than the value obtained through actual measurements, as the calculation assumes complete oxidation under theoretical conditions； In reality, the reagents we use are not capable of oxidizing everything; there is always a portion that cannot be oxidized. You can use methanol as an example: the COD value of a 0.1% methanol solution is 1500 mg/L. As mentioned above, inorganic substances have no effect on COD