Anaerobic wastewater treatment is the biological treatment of wastewater without the use of air or elemental oxygen. There are a number of applications that focus on the elimination of organic pollutants from wastewater, slurries and sludges.
Biogas, a mixture of methane and carbon monoxide, is the end product when organic pollutants are converted.
(COD)”chemical oxygen demand” is the measurement of weight it takes to oxidize organic pollution chemically.
The oxygen weight measurement called COD is basically the level of organic material it contains. The best way to appreciate anaerobic wastewater treatment is to compare its COD balance with that of aerobic wastewater treatment.
Through the Anaerobic Treatment, methane, a valiable fuel, is produced by converting the COD from wastewater.
Only a slight amount of COD is converted to sludge; and very little inputs are necessary to operate such a system.
With the Aerobic Treatment the COD in wastewater is greatly to converted sludge, a heavy waste product, and is not so cost effective for removal.
Aerobic wastewater treatment plants basically produce waste sludge.
The process requires a great deal of energy as Oxygen must be supplied continuously by aerators.
Range of Applications; for the most part environmental engineers are aware that anaerobic processes are used to stabilize sludge such as a sludge digester at municipal treatment plants.
As a matter of fact “high rate” anaerobic wastewater treatment technologies can also be utilized to treat and dilute the concentrated liquid organic wastewaters such as; breweries, factories, petrochemical, farming, rivers, lakes,
Anaerobic technologies can have a very beneficial impact on munical wastewater sewage treatment.
Anaerobic treatment is used by full scale plants and have been documented world-wide for the treatment of industrial effluents.
Anaerobic technologies is not only beneficial for COD it can also be utilized for the biodegradation or biotransformation of toxic priority pollutants
Microbial communities in anaerobic environments can either cause the oxidation of the pollutants resulting in its mineralization to benign products for example CO2, or they can cause the reductive biotransformation of pollutants to less toxic substances for example: dechlorination of polychlorinated hydrocarbons.
It’s possible for anaerobic bioremediation to occur in bioreactors, for example in the treatment of industrial effluents which contain toxic pollutants, or it can occur on location in groundwater or sediments at sites that are contaminated.
Amid the most successful applications of anaerobic treatment for the oxidation of toxic pollutants is the case of the treatment of effluent in the plastic industry containing high concentrations of terephthalate.
These effluents are commonly elevated in COD and aerobic treatment would result in extreme sludge production.
A complicated microbial bunch of anaerobes can be maintained in bioreactors that allow the complete conversion of terephthalate into carbon dioxide and methane in high rate anaerobic bioreactors.
(PET) polyethylene terephthalate industry has now fully accepted anaerobic technology as the main biological treatment of wastewater technology for effluents.