i²-Sens

Development of innovative and intelligent sensor systems to ensure biological process stability during load-flexible operation of biogas plants

Topic

The load-flexible, demand-oriented operation of full-scale biogas plants is becoming increasingly important. After biogas plants have continuously produced biogas for many years, their future role in the regenerative-based energy supply will be to balance the fluctuating electricity production from wind energy and photovoltaics. This requires a change in the mode of operation to a strongly fluctuating plant feed, both daily and seasonally, in order to meet the fluctuating biogas demand. This requires a reliable forecast of the biogas demand and a derived forecast of the biogas production. This work has already been implemented very successfully in a model predictive control in the predecessor project "PowerLand 4.2" around Celina Dittmer, Johannes Krümpel and Andreas Lemmer.

Goals

In a further step towards a holistic application of demand-oriented biogas production in full-scale plants, these models are to be extended to include process monitoring. This is necessary, for example, in order to react early to critical conditions in highly flexible feeding. For this purpose, complementary measuring techniques for temporally high-resoluting and highly accurate measurements of the biogas composition are to be used within the framework of i²-Sens. Based on these parameters, conclusions on process stability and efficiency will be drawn and integrated into the existing models for flexible feeding. 

Project tasks of the State Institute

The measurement technology developed in the project is located in an air-conditioned measurement van, which has been at the research biogas plant at Unterer Lindenhof since summer 2022. Currently, the measurement van is equipped with gas analyzers (infrared & UV spectrometers, electrochemical sensors), which are used to determine the biogas components with high temporal resolution. In the course of the project, further measurement technology will be installed. First tests on load-flexible operation were started in autumn 2022. The aim of these trials is to investigate the influence of feeding frequency on process stability. The project is coordinated by the state institute. In addition to the installation and validation of the gas measurement techniques, we investigate the relationships between biogas process and biogas composition in order to derive efficient feeding strategies for a stable and demand-oriented biogas production.