Low energy gas or Biogas, is typically defines a gas resulting from the anaerobic (in absence of oxygen) decomposition of organic material like:
• Municipal waste leftovers - resulting in landfill gas;
• Sewage waste (the mixture of waste from the human body and used water that
is carried away from houses by pipes under ground) - resulting in digester gas;
• Energy crops (corn, wheat, grass) - resulting in industrial biogas;
• Liquid manure or dung - resulting in agricultural biogas.
Biogas is a gas with 50-70 % of methane (CH4) and 30-50 % of carbon dioxide (CO2) content. It is a renewable fuel with a special composition which demands proper addressing in both, plant layout as well as in engine / genset design.
Typical chemical composition of biogas depends on:
- quality and composition of the input biomass material (vegetal, animal, etc.);
- operation of the plant, specially temperature and pressure in the fermenter.