Short general project overviewEphyra® is a sludge digestion technology developed in the Netherlands and patented by Royal HaskoningDHV (RHDHV). With the innovative configuration and control of the process, it is possible to treat sewage sludge in a sustainable and cost-efficient way and convert it into biogas or make it suitable for land application (as fertilizer). The system has been tested, installed and proven in the Netherlands. Next step is the international market introduction, starting with a pilot project in Canada. A feasibility study is necessary to gain detailed insights into the potential of an Ephyra® (pilot) project in Canada. An objective and rational estimation of the technological innovativeness and economic possibilities must be made.RHDHV has, in collaboration with OCWA, identified a site for a pilot project in Canada. Both partners consider a study into the opportunities, risks and threats of the intended pilot project necessary as the first step towards the application of Ephyra® by OCWA. This feasibility study must also provide insight into what resources are needed to realize the project and what the chances.Initial activities and results of the projectThis feasibility study must provide insight whether and how the Ephyra® pilot project can be implemented at a WWTP of OCWA west of Toronto to contribute to the water security in the region.The project results/deliverables are: - 1 report on the contextual aspects including a stakeholder, competitor and SWOT analysis - 1 report describing potential (local) partners for pilot implementation and scale-up - 1 report with potential sites for full-scale implementation/replication in Canada- 1 report with an overview of the legal, institutional and technical aspects applicable to the pilot- 1 report with an overview of the legal, institutional and technical aspects applicable to the pilot- 1 business case for pilot scale application- 5 business cases for a full-scale installation in Toronto- 1 report with the pilot project outline and an overview of resources required for implementation- 1 business model/plan for upscaling in CanadaThe planned resultsThe conclusion of the feasibility study was that the technology is technically and economically feasible. The main conclusions were:- Model calculations, lab and pilot testing, and the performance of the full-scale Ephyra® at WWTP Tollebeek all (re)confirm the potential and specific features of Ephyra® as a new, innovative sludge digestion technology.- The plug flow regime of Ephyra® combined with the patented Ephyra® controller allows the system to operate at short retention times (5-8 days under average and peak conditions).- The short retention time of Ephyra® has the benefit that smaller reactor volumes are used, which saves on investment costs (CAPEX). - Also, capacity of existing systems can be more than doubled by retrofitting it to an Ephyra® configuration including an Ephyra® controller. Investments for extending capacity of existing digesters can be reduced significantly compared to the construction of new, additional digesters. With regards to business case, the general conclusions were:- For very small WWTP’s (e.g. St Mary’s) there appears not be a positive business case for Ephyra® because of too low revenues. On the other the extra CAPEX for Ephyra® is also low so that non-financial drives may give reason to introduce Ephyra®.- For WWTP ‘s with planned extension in digestion capacity a retrofit to Ephyra® appear attractive. CAPEX for Ephyra® is lower than conventional extension or the extra CAPEX is relatively small giving an acceptable payback time (less than 7-8 years).- For larger WWTP’s without extension of the digestion capacity, and dependent of the existing situation, a retrofit to Ephyra® can be attractive. In the Kitchener case calculated in this report the payback time for Ephyra® was 5.5 years. This illustrate that also for existing WWTP’s without extension an Ephyra® retrofit can be attractive. This should be judged separately for each case.Based on these conclusions, a pilot proposal was developed for testing the technology in Canada. The proposal was accepted for Partners for Water funding in the second tender of 2019.What makes the technology, product, method or approach used innovativeThe Ephyra® concept patented by RHDHV is innovative from different perspectives:- Capacity & yield - with 50% less space and a retention time of only 8 days, a comparable quantity of biogas is produced in comparison with a conventional digestion with a residence time of 20 days. An Ephyra® of 8 days including 13 days secondary fermentation produces about 20-30% more biogas than a conventional digestion with a residence time of 20 day; - Process & operation - separating the digestion steps into different compartments creates a highly efficient and controllable system without the complexity of alternative technologies;- Applicability & costs - The robust system can be used as pre-treatment (easy-to-retrofit expansion) for existing installations or as stand-alone sludge digestion on a large or small scale against lower CAPEX and OPEX compared to alternatives.