This is according to Denniz Erol, CEO of More Biogas Småland AB. The company was founded in 2011 and has played an important part in the development of biogas in the Kalmar region when the regional public transport authority made a major investment in biogas.
Waste becomes biogas
At the plant in Läckeby, next to the E22 motorway near Kalmar, they receive manure from farms as well as food waste, slaughterhouse waste and waste from local food production.
“We have a reception hall with a tank where the lorry arrives and unloads the food waste, manure and so on. It is ground down to a size of under twelve millimetres. Everything is then mixed in the digester, where the gas is formed,” says Denniz Erol.
Challenges
They also receive solid manure, such as bedding from animal stalls, and straw that cannot be used for other purposes, for example due to mould.
“We tried using garden waste for a while, but it did not work. It contains too many unwanted materials such as crisp packets and other plastics.”
Another challenge in biogas production is that the digester can fill up with sand residues. Eventually it must be emptied, which can affect production.
Manure contains large amounts of water, which leads to heavy transport volumes. In Läckeby, studies have been carried out on methods for separating the solid and liquid fractions of manure, a project in collaboration with RISE, SLU and Baltic Waters. One aim is to reduce the release of nutrients into the Baltic Sea.
Purification
The raw gas from the digester must be purified. This is done using carbon filters and chemical cleaning that removes hydrogen sulphide, carbon dioxide and water from the gas. The finished biogas is then delivered to ST1, which is responsible for distribution. More Biogas also operates a public filling station.
More Biogas has also developed a logistics system for substrates (the material fed into the digester) and for biofertiliser (the residue after the process). An external haulage contractor manages transport to and from the farms.
Few empty transports
“We can deliver the biofertiliser wherever the farmers wish, for example to satellite tanks near the fields. Then we collect substrate from the farm and transport it to the biogas plant. In this way, we avoid empty runs. And the farmer does not need to move the biofertiliser far after we deliver it.”
Denniz Erol emphasises the importance of producing biogas locally.
“It is not only about sustainability and local production. The raw material is waste, something many people want to get rid of. But it can be converted into something we need. In times of emergency, biogas can even be used to produce electricity if necessary. The biogas system is flexible in many ways,” says Denniz Erol.
