of Digestate for Sustainable Cycle Systems of Carbon, Nitrogen and Phosphorus
solutions, anaerobic digestate, biofertilizer, nutrient cycles, sustainable
Short workshop abstract: The
digestate is a by-product of the anaerobic digestation process that has been
successfully used as biofertilizer and a valuable source of major plant
nutrients, which are essential for plant growth, soil fertility and therefore
sustainable crop production. Strategies that improve the availability of
nutrients in soils, in particular, C, N, P can help meet targets for
nutrition security, soil conservation, and reinforce a multidisciplinary
approach. A well-designed waste management strategy along with the concept of
circular economy presents a restorative and regenerative option for
sustainable digestate management in Hokkaido and Linköping. System analysis of biogas plants in the region of Hokkaido shows the
potential for digestate application in nutrient recycling. Existing problems
on biogas plants can be solved through such steps: biogas plants should be
operated without feed-in tariff; new business should be launched, like
Shikaoi town; re-recognition of value of digestate as fertilizer is needed.
In the case of Japan, due to the fact that the land is small, and the
mixture of urban and rural areas is progressing, there is a lot of composting
and purification treatment that is not common in Europe and Sweden. This
strategy will be compared with the Nordic model for biogas production. The results of carbon accumulation in the soil after long-term digestate
application will be presented. One of the most perspective substrate and
option for biogas production is digestate utilization for algae cultivation.
Therefore, innovative technology related to diffusion-driven nutrient
extraction systems with no energy will be discussed.