In Case study 3 a Yeast-based Citric Acid Bioprocess was successfully implemented at demonstration scale using carbon low kitchen cleaning wastewater and waste frying oil as C-rich source. During the second half of 2017, UFZ focused on the further development of efficient modes for the Citric Acid production by the yeast Yarrowia lipolytica, in particular on the preferred bioprocess optimization via robust fed-batch substrate feeding strategies as well as on the online sensor system for citric acid or substrates (triglycerides) assessment. Furthermore, essential issues were addressed such as temperature and oxygen management and control (development of a heat exchanger unit, improvement of air supply).
In the Anaerobic Co-Digestion (AcoD) process at demonstration using a mixture of waste frying oil and concentrated yeast biomass, 1.32 L biogas per kilogram per day were achieved while with concentrated yeast biomass as mono substrate 1.45 biogas per kilogram per day were achieved at demonstration scale.
The Hydrothermal Carbonization (HTC) Plant at 50 L-demo scale in Bad Koenigshofen, the detailed planning is completed, so that in 2018 digestate samples for HTC treatment can be tested.
Design of 50 L HTC plant at Bad Koenigshofen, Germany (RENERGIE)