Treatment of biowaste


​Biowaste is a valuable raw material. We transport biowaste to the Ämmässuo Waste Treatment Centre in Espoo where we use it for producing biogas and compost.

The treatment plant for biowaste comprises a composting facility, completion in 2007, and a biogas facility, completion in 2015. The old composting facility of 1998 will still be used for composting wastewater sludge.

Recycling energy and nutrients

Treatment of HSY’s biowaste is based on the part-stream dry digestion where biowaste is digested and composted. The most suitable parts of the biowaste are selected and directed to each treatment process. Thanks to the biogas production, the part-stream dry digestion technique is ecologically a more sustainable treatment than composting. The treatment process is optimised in the KOMBI project.

Due to the biogas facility we are able to recover energy from biowaste efficiently. In addition to this, we release humus and valuable nutrients, such as phosphorus and nitrogen, back into circulation. At the same time, odour hazard and wastewater emissions ensuing from biowaste treatment are minimised.