Dr Francesco Ometto completed his ATBEST fellowship in March 2016. We catch up with him to find out how his career has progressed.
After two years at Scandinavian Biogas as Experienced Research working on ATBEST, the company offered me the possibility to stay and take the lead of a new EU project submitted by Professor Jörgen Ejlertsson back in 2014. I could not refuse such a great opportunity.
EffiSludge for LIFE is a project that aims to demonstrate the advantage for operating conventional Activated Sludge Plants (ASP) at low sludge age. This is contrary to the standard operation, where high sludge ages are preferred to maintain low growth rates and therefore minimising the cost of sludge disposal.
In the project, an existing ASP located at the Norske Skog Skogn mill - the largest producer of newsprint in Norway will be modified to achived the flexible operation required by EffiSludge conditions. Treating approximately 20 000 m3 of wastewater per day, the ASP currently operates with a sludge retention time close to 18 days and external nitrogen and phosphorus is added into the system to secure biomass growth.
The EffiSludge concept
By lowering the sludge retention time below 10 days, higher sludge production occurs and lower aeration is required per unit of treated wastewater. Lower the aeration needed, lower the energy demand and the related carbon emissions. Furthermore, to justify the higher amount of sludge produced, this will be processed onsite for biogas production capable, in principle, to satisfy part of the heat and power required by the mill.
A new integrated AD plant
In the specific context of the Skogn site, the produced excess activated sludge will be co-digested with fish waste adding to the stream of rejected water post anaerobic digestion a high load of nitrogen and phosphorus. Recirculated in the WAS system, such loading of nutrients could be able to offset current external dosing of nitrogen and phosphorus. With a capacity of 25 million (12.5 in the first year) cubic meters of liquefied biogas (LBG), the plant is currently under construction and it is expected to enter in operation by the end of 2017.
Linked to the work on seaweed digestion completed as ATBEST fellow, I am also involved in a parallel project, receiving financial contribution from the Research Council of Norway. The COMPLETE project investigates the possibility to integrate the new AD facility at Skogn with algae production – both seaweed and microalgae – to enhance an energy efficient biogas production by recirculation of nutrients and complete utilisation of resources (COMPLETE).
25 years of LIFE
The project is entitled of 1.8 million Euro as financial contribution from the European programme LIFE celebrating this year its 25th anniversary. Launched in 1992 and investing so far more than 3.4 billion Euro, LIFE is the main instrument for the European Commission to support the development of the action plan for Climate Change Mitigation and Environment. Coordinated by Scandinavian Biogas Fuels AB, EffiSludge for LIFE (LIFE14 CCM/SE/000221) is implemented in cooperation with Biokraft AS (Associated Partner) and Norske Skog Skogn. Started in September 2015, the project will last until December 2019.
Project website: http://scandinavianbiogas.com/effisludge/