• Blog
  • Wastewater Testing
  • Bioaugmentation Applications
  • Useful Information
  • About Us
BIOLOGICAL WASTE TREATMENT EXPERT
Contact Us

Anaerobic & anaerobic contact process as wastewater pretreatment

11/3/2017

 
Picture
Anaerobic waste pretreatment extends back to the earliest Imhoff and septic tank waste treatment systems. While these early systems were passive with no mixing or biosolids recycling, they biochemically operate in the same manner as the latest in fluidized bed anaerobic reactors. Unlike digesters where methane production and solids stabilization is the primary goal, anaerobic pretreatment is concerned with hydrolysis of complex molecules converting the complex and insoluble organics into short chain volatile fatty acids (VFA). The conversion into VFA does reduce BOD/COD concentration via creation and maintenance of microbial cells. If the anaerobic pretreatment system produces methane - from the growth of methanogens on VFA - the BOD/COD reduction is much greater than a system with no methanogen activity. 

We see anaerobic pretreatment with high strength wastewater that would be difficult and cost prohibitive to treat in a standard aerobic system - maintaining D.O. would require a massive amount of energy. One common application of anaerobic pretreatment is in meat processing wastewater. Often these systems have an anaerobic basin with a grease cap or physical cover following DAF or other pretreatment system. The anaerobic basin microbes grow on soluble organics and via anaerobic biochemistry begin to reduce the carbon chain length making insoluble fatty acids more soluble. This is a much slower process under anaerobic conditions than in an aerobic system resulting in the "grease cap".  With a relatively long residence time, the anaerobic pretreatment removes a substantial portion of influent BOD and converts proteins into ammonia which is amenable to rapid treatment in the following activated sludge unit.

While meat processing is a common application of anaerobic pretreatment, it is also useful in many waste streams with long chain organic compounds that require solubilization to become BOD5. Examples include cellulose, fats, and large particulate material.


Comments are closed.

    Author

    Erik Rumbaugh has been involved in biological waste treatment for over 20 years. He has worked with industrial and municipal wastewater  facilities to ensure optimal performance of their treatment systems. He is a founder of Aster Bio (www.asterbio.com) specializing in biological waste treatment.

    View my profile on LinkedIn

    RSS Feed

    Click to set custom HTML

    Archives

    December 2022
    November 2022
    October 2022
    September 2022
    August 2022
    June 2022
    May 2022
    March 2022
    February 2022
    January 2022
    November 2021
    October 2021
    September 2021
    August 2021
    June 2021
    April 2021
    March 2021
    February 2021
    December 2020
    November 2020
    October 2020
    September 2020
    August 2020
    July 2020
    June 2020
    May 2020
    April 2020
    March 2020
    February 2020
    January 2020
    December 2019
    November 2019
    October 2019
    September 2019
    August 2019
    July 2019
    June 2019
    May 2019
    April 2019
    March 2019
    February 2019
    January 2019
    December 2018
    November 2018
    October 2018
    September 2018
    August 2018
    July 2018
    June 2018
    May 2018
    April 2018
    March 2018
    February 2018
    January 2018
    December 2017
    November 2017
    October 2017
    September 2017
    August 2017
    July 2017
    June 2017
    May 2017
    April 2017
    March 2017
    February 2017
    January 2017
    December 2016
    November 2016
    October 2016
    September 2016
    August 2016
    July 2016
    June 2016
    May 2016
    April 2016
    March 2016
    February 2016
    January 2016
    December 2015
    November 2015
    October 2015
    September 2015
    August 2015
    July 2015
    June 2015
    May 2015
    April 2015
    March 2015
    February 2015
    January 2015
    December 2014
    November 2014
    October 2014
    September 2014
    August 2014
    July 2014
    June 2014
    May 2014
    April 2014
    March 2014
    February 2014

Proudly powered by Weebly
Photos used under Creative Commons from Picturepest, marcoverch, perzonseowebbyra, Picturepest, Picturepest, dsearls, dungodung, Massachusetts Office of Travel & Tourism, aqua.mech, vastateparksstaff, hile, Aaron Volkening, amishsteve, Neil DeMaster, mklwong88, KOMUnews, Picturepest, kaibara87