20.07.2020 - Biogas plant exploits manure and other waste to produce biomethane

The Danish company Naturbiogas Sode builds a biogas plant in order to annually digest 264.000 tons of biomass. Stallkamp delivers three continuous stirred tank reactors and an additional storage tank made of stainless steel for this plant.  

Input of the biogas plant

To reach the annual biomass of 264,000 tons, 700 tons of substrate are necessary every day. This consists of roughly 50% manure, 40% solids and 10% glycerin. The manure is mainly pig slurry, whereas, the solids are residues from an olive and soap production as well as chicken manure, deep litter, gras and corn. The feeding system is a walking floor including a liquid feeding system. It is necessary to prepare the solids for digestion. 

Digestion in stainless steel tanks

The fermentation process covers usual digesters as well as three continuous stirred tank reactors. They have a capacity of 9.000m³ at a height of 20m. The continuous stirred tanks lead to improved stirring and mixing results. The retention time is about two months. 

The stainless steel digesters are very durable and robust. There will only be minor repairings. The biogas digesters have a stainless steel roof. In the middle of the roof is the motor of the central stirring system. The single stainless steel sheets are assembled to form rings which are than lifted up with jacks. 

Output

The estimated biogas production will be roughly 17.600.000m³ biomethane per year. This means that the plant produces 3,600m³ biogas per hours which is upgraded to 2.000m³ biomethane. The plant transforms one ton input into 66m³ biomethane. 

Additional storage tank

Glycerin as an input needs to be tempered. Therefore Stallkamp delivers an additional storage tank with heating and cladding. The tanks stores 500m³ glycerin and covered by a stainless steel roof. A submersible motor mixer fully made of stainless steel stirs the glycerin in the tank. Other equipment of the tank are inspection openings, wall bushings etc.