Today I want to talk about biogas, you might have heard about it but maybe you don’t know how it works exactly!Simply saying to produce biogas, you put organic material (waste) in a closed room (digester) and microorganisms will do the rest.
It is not only used to produce biogas but also to some how get rid of the sludge in waste water treatment plants (WWTP), because disposal of sludge in WWTP represents up to 50 percent of the current operating cost of the plant so through the anaerobic digestion (no Oxygen) you can protect the environment and optimize the WWTP costs and also produce biogas to generate electricity!
In the picture below you can see the different stages of a typical WWTP:
So as I said it would be very beneficial, as you can reduce the amount of final sludge, produce biogas for electricity or heating and you will also have some co-products like fertilizer or nutrients.
At the end I would like to cite a paragraph from a paper published by M. Mohammadi et al; “The potential of biomass sources in Iran is estimated to be 132 million ton (oil equivalent) in the form of agricultural and forest wastes, livestock wastes, municipal wastes, sewage and industrial wastes. Taking into account the usual amount of biogas yield from agricultural wastes, animal wastes, municipal wastes and industrial and municipal wastewater and with good safety factor, biogas in Iran will generate about 16146.35 million m3 which is approximately 323 peta joule (10^15) of energy. Iran is among the countries which have vast resources for biogas production. Despite high biogas potential and simple technologies of generators and reactors of biogas, unfortunately, the use of these resources in the country is limited. So it means that more attention and research is needed in this field.”