Biogas can be produced from many types of organic waste, which is often produced in large quantities in agri- and food processing-related industries, using well-established technologies that have been improved over decades.

Biogas is produced via anaerobic digestion of organic matter.  Anaerobic digestion is a series of processes in which microorganisms break down biodegradable material in the absence of oxygen, producing a mixture of methane and carbon dioxide.  The biogas has many applications: burned directly in boilers to produce heat and steam; combusted in gas engines to produce electricity; or purified into almost pure methane and sold as natural gas.  Biogas is also produced in large quantities at landfill sites (often referred to as landfill gas or LFG).

Nollen Group has experience in all these applications as well as many different technologies used for anaerobic digestion, such as covered lagoons, continuously-stirred tank reactors (CSTRs) and upflow anaerobic sludge blanket reactors (UASBs).

Nollen Group has also worked with many feedstocks from food processing waste, such as pineapple, corn and starch, to farm and urban wastes.