CHEMICAL OXYGEN DEMAND (COD)

Chemical Oxygen Demand

 COD

 

 

Hanna Instruments offers a variety of instrumentation for measuring Chemical Oxygen Demand (COD).  From benchtop meters and Photometers to certified reagents, Hanna has an accurate, affordable solution for nearly any COD application.  Choose a category above to learn more about our COD testing products. 

The HANNA COD method is based on the well established closed dichromate-reflux colorimetric method.

What is Chemical Oxygen Demand (COD)?

Chemical oxygen demand (COD) test is commonly used to indirectly measure the amount of organic compounds in water.Most applications of COD determine the amount of organic pollutants found in surface water.

How is COD measured?

It is expressed in milligrams per liter (mg/L), which indicates the mass of oxygen consumed per liter of solution. Older references may express the units as parts per million (ppm).

Why Measure COD?

COD is often measured as a rapid indicator of organic pollutant in water. It is normally measured in both municipal and industrial wastewater treatment plants and gives an indication of the efficiency of the treatment process. COD is measured on both influent and effluent water. The efficiency of the treatment process is normally expressed as COD Removal, measured as a percentage of the organic matter purified during the cycle.

What is Biochemical oxygen demand (B.O.D.)?

Biochemical oxygen demand or B.O.D. is the amount of dissolved oxygen needed by aerobic biological organisms in a body of water to break down organic material present in a given water sample at certain temperature over a specific time period.

B.O.D. and COD

Biochemical Oxygen Demand (BOD) is an empirical test that determines the relative oxygen requirements of wastewater, effluent and polluted waters. BOD tests measure the molecular oxygen utilized during a specified incubation duration for the biochemical degradation of organic material (carbonaceous demand) and the oxygen used to oxidize inorganic material such as ferrous iron and sulfides. The most common BOD test consists of a 5 day period in which a sample is placed in an airtight bottle under controlled conditions temperature (20ºC ± 1ºC), keeping any light from penetrating the sample to prevent photosynthesis. The Dissolved Oxygen (DO) in the sample is measured before and after the 5 day incubation period, and BOD is then calculated as the difference between initial and final DO measurements. BOD can be considered a more "natural" test in determining the oxygen required to oxidize organic matter, however it does not account for rapid changes in conditions. COD is often preferred for daily analysis since it is inherently more reproducible, accounts for changing conditions and takes a short time to complete

 

   
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HI83399-02 Multiparameter Photometer - Water...

HI83399 is a compact, multiparameter photometer for...

R 28,026.00 *

HI 740235 COD Adapter for HI 83099

HI 740235 COD Adapter for HI 83099

R 193.00 *

HI 83224-02 COD/multiparameter photometer...

COD/multiparameter photometer w/bar code recognition of...

R 32,697.00 *

HI93754H-25 COD Reagents, Low Range

HI 93754H-25 COD Reagents, Low Range

R 1,259.00 *

HI93754G-25 COD Reagents, Medium Range, ISO

COD Reagents, Medium Range, ISO

R 1,259.00 *

HI93754F-25 COD Reagents, Low Range, ISO

HI 93754F-25 COD Reagents, Low Range, ISO

R 1,259.00 *

HI93754E-25 COD Reagents, Medium Range,...

Reagents for COD, Medium Range, mercury free* *This...

R 1,028.00 *

HI93754D-25 COD Reagents, Low Range, Mercury...

Reagents for COD, LR, mercury-free* *This method is...

R 1,028.00 *

H93754C-25 High Range COD Reagent (0 to...

COD Reagent kit for 25 test vials (O2)

R 1,259.00 *

HI93754B-25 Medium Range COD Reagent (0 to...

COD Reagent kit for 25 test vials (O2)

R 1,259.00 *

HI93754A-25 Low Range COD Reagent (0 to 150...

COD Reagent kit for 25 test vials (O2)

R 1,259.00 *

HI740217 Lab Safety Shield

Laboratory bench safety shield for COD measurement

R 1,658.00 *

   
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