Water for BOD

Application Overview

• Dilution method
  This is a standard method. As an example, the APHA standard methods 5210B from the American Public Health Association describes in detail this protocol. Dilution water is prepared by adding inorganic nutrients and buffer salts to purified water. If the sample does not contain sufficient amounts of bacteria, or contains compounds toxic to bacteria (e.g. chlorinated effluent), it may be necessary to add microbial seed as well. Various dilution levels of the sample water are then prepared using the dilution water. The BOD bottles are filled to the top, capped and sealed. They are incubated in the dark at 20°C for 5 days. The levels of dissolved oxygen are measured prior to and after the 5-day incubation period. The difference between these two values, corrected for the dilution and the blank, is the BOD5 value. BOD tests results are expressed in mg/L of dissolved oxygen.
  
  
• Manometric method
  In this test, a manometer is fitted into a bottle containing the undiluted sample. It continuously measures the drop in air pressure in the bottle, which reflects the amount of oxygen uptake by the sample. This method is easier than the dilution method because no dilution is necessary, and continuous measurements are obtained.

More Information

• BOD Doctor: http://www.boddoctor.com/wiki/index.php?title=Main_Page 
• Standard Methods for the Examination of Water and Wastewater - 5210 - BOD: http://www.polyseed.com/misc/bod-std%20methods-8.04.pdf 
• BOD Solutions: http://www.perrybrake.com/BODSolutions.html

Feel free to express your comments

top