Optical Analyses: More Efficient Biogas Facilities
Innovations Report, July 12 2011
When biomass is fermented to produce methane, acids are created, and if the acid concentration gets too high, the process collapses and the facility has to be cleaned and started up again. Operators currently check the chemistry within the tanks by taking random samples every few days and sending them to a lab for analysis. The new technique developed by Siemens researchers at Corporate Technology directly measures the acid content within the fermenter. Because many operators don’t know how much acid is in the fermenter at any one time, many run the facilities at a level far below that at which the system could break down, accepting losses of up to €100,000 in the process. This problem can be solved with the help of infrared spectroscopy. Molecules produce characteristic light spectra when irradiated with infrared light.
These spectra provide information about the chemical bonds, from which the presence of certain elements or chemical groups can be deduced. The device developed by Siemens measures the fermenter’s acid content by shining infrared light through a glass window. The researchers are also developing a method for testing the quality of the biomass so that the facility can be fed in a more targeted manner.