faq
What is Biogas?
It is the gas that is released during the breakdown/decomposition/fermentation of organic matter in the absence of oxygen. Biogas is made up of mainly of methane and carbon dioxide. The smaller volume gases would be hydrogen sulphide, hydrogen, nitrogen and oxygen. Biogas can be used as it for cooking purposes or combusted in a turbine or combined heat and power unit to produce electricity and heat.
Organic waste such as dead plant and animal material, animal feces, and kitchen waste can be converted into a gaseous fuel called biogas. Biogas originates from biogenic material and is a type of biofuel.
Where is the gas stored?
The gas generated in a digester is stored in a double membrane, gas tight roof.
Are there any safety measures in place?
All biogas plants are equipped with EGB (emergency gas burners) that flare up excess gas. This is only necessary when the gas volumes reach a critical points set by the operator of the plant.
What is the average size of a digester?
The size of a digester depends on volume of substrate used. They range from 7.7 meter to – 30 meter in diameter. With a standard height of 6.3 meter.
What happens to the post digested substrate?
The post digested material is a bio-fertilizer. It can be used as liquid fertilizer that is sprayed onto the field as it is mostly done in Europe. The modus of use depends on the legislation of the country.
Another common modus is to integrate a screw press separator. Thus producing fertilizer which can further beneficiated, bagged and marketed.
Can abattoir waste be used in a biogas plant? What about it's hazardous nature?
Abattoir waste can definitely be used in a biogas plant.
Yes it is hazardous, and contains harmful pathogens. We therefore pasteurize abattoir waste at 72 deg/c before we allow it to fed into the digesters.
What type of digestion process do you use?
Anaerobic digestion and the mesophylic process.
Is there a way to monitor these plants?
Yes. For all of our plants we require an ADSL line for dial-in monitoring. Twice a day we dial into the system and monitor the gas production, feeding schedules etc. Should there be a problem it will be picked up. There are also many sensors throughout the plant that monitor all levels. Also an alarm is triggered, informing the operator of the situation via sms.
How is the temperature within the digester maintained to keep the process constant?
Polystyrene insulation under and around the tank help to prevent or minimise temperature losses, even during a breakdown or malfunction.
Do biogas plants work in areas where temperatures are well below zero ?
Yes, we have quite a few plants in Germany that work throughout even in cold and strong winters.
What gas does a biogas plant emit?
The engines emit CO2 no higher than what a truck engine emits. In the event of too much gas production we prefer to release CO2 into the atmosphere rather than methane (CH4). Methane is 21 times more harmful to the environment than CO2