Bakery waste is a tasty biogas plant feedstock

Porokylän Leipomo has reduced side streams and biowaste to a minimum but all the same still sends them each month to feed Gasum’s biogas plant in Kuopio.

When a bakery makes around four million kilograms of bread and other bakery products a year, there is bound to be some food waste and biowaste. Porokylän Leipomo has actively addressed, and according to quality manager Joonas Pelo has been highly successful minimizing the amount of waste.

“We have identified food waste, brought it to the forefront and held workshops to think about how to reduce the amount of biowaste. In 2020, we got biowaste down to 180 tonnes.”

The bakery food waste consists of production side streams such as pastry edges, product rejects and flour from the floor. The biowaste was recycled earlier, too, but spring 2020 saw the dawn of a new era in further processing with an agreement signed with Gasum.

The bakeries in Nurmes and Lieksa now send their biowaste on average once a month to the Kuopio biogas plant, where it is processed into biogas for a traffic fuel. The remaining digestate is a nutrient-rich recycled fertilizer for arable farming.

A local transport firm is responsible for taking the full ozonated biowaste container to Kuopio and for returning it empty and washed. Pelo has been highly pleased with the collaboration on all sides.

“Careful background work and planning made deployment painless and everything has worked perfectly. All in all, everything is very positive.”

Steady steps in responsibility

Marketing manager Marika Pulkkinen says that Porokylän Leipomo is increasingly highlighting the responsibility aspect in its operations.

“We spent two years developing a lighter EcoCompass environmental management system suitable for SMEs and we have now brought this into use. Both of our production facilities use fully renewable energy, in other words wind power.”

Careful sorting in waste management, modern equipment and optimal emptying frequency are part of the goal to reduce carbon dioxide emissions. Biowaste accounts for the most waste, but by no means all waste goes into the wastebin.

“We have long donated surplus products to charity,” Pulkkinen says.

Organic waste is a tasty feedstock

Gasum has a number of biogas plants like the one in Kuopio, which typically process an average of 60,000 tonnes of biowaste a year. Biogas production is a good example of fully utilizing raw materials and promoting the circular economy. According to Anniina Hiltunen, Sales and Key Account Manager, Gasum the bakeries send them tasty feedstock.

“The organic waste from the bakeries is one of our favorite feedstocks. All clean as well as packaged organic waste from grocery stores is a good biogas feedstock, as of course are all other organic side streams from production.”

The Kuopio plant is beginning to run at full capacity and expansion plans are already advanced, while at Porokylän Leipomo in Nurmes, Pelo is thinking of possibly taking the following steps.

“Our ovens cannot run on biogas, which from the responsibility perspective would be an excellent choice. We need to put further pressure on the equipment manufacturers.”

17.3.2021