What is Chemical Oxygen Demand (COD)? Chemical oxygen demand (COD) is the amount of dissolved oxygen that must be present in water to oxidize chemical organic materials, like petroleum. COD is used to gauge the short-term impact wastewater effluents will have on the oxygen levels of receiving waters.

Chemical oxygen demand (COD) is the amount of dissolved oxygen that must be present in water to oxidize chemical organic materials, like petroleum. COD is used to gauge the short-term impact wastewater effluents will have on the oxygen levels of receiving waters.

The Dichromate Chemical Oxygen Demand (COD) test measures the oxygen equivalent of theamount of organic matter oxidizable by potassium dichromate in a 50% sulfuric acid solution.

Chloride is the primary interference when determining COD concentration. Each COD vial contains mercuric sulfate that will eliminate chloride interference up to a maximum Cl – concentration of 2000 mg/L. Summary of method The mg/L COD results are defined as the mg of O 2 consumed per liter of sample under conditions of this procedure.

chloride concentrations (near maximum concentration) and low COD concentrations. If sample dilution causes the COD concentration to be too low for accurate measurements, add 0.50 g of mercuric sulfate (HgSO 4) to each COD vial before the sample is added. The additional mercuric sulfate will increase the maximum chloride

OXYGEN DEMAND, Chemical OxygenCOD_None_Mid_RCD_Eng_4000.fm Page 1 of 6 DR/4000 PROCEDURE OXYGEN DEMAND, Chemical Method 8000 Reactor Digestion Method* (0 to 150.0 mg/L COD) Scope and Application: For water, wastewater and seawater; digestion is required; USEPA Approved** for wastewater analyses.

Hach's USEPA-approved dichromate COD Method is the most widely used chemical oxygen demand (COD) method for NPDES reporting in the

OXYGEN DEMAND, Chemical, continued Example: Dilute the sample to a range of 90 to 4500 mg/L COD Standard test range is 50 to 1000 mg/L COD. It is best to use 0.5 mL or more of sample for diluting. If sample values exceed 18,000 mg/L COD, use a separate sample dilution before performing the sample chloride removal procedure. 9. Label each Mn III

The Dichromate Chemical Oxygen Demand (COD) test measures the oxygen equivalent of the amount of organic matter oxidizable by potassium dichromate in a 50% sulfuric acid solution. Generally, a silver compound is added as a catalyst to promote the oxidation of certain classes of

Chemical oxygen demand (COD) is defined as “a measure of the oxygen equivalent of the organic matter content of a sample that is susceptible to oxidation by a strong chemical oxidant.*”