Optical Absorption Spectroscopy Technology

The optical absorption spectroscopy used in our online biogas quality monitoring sensor BioSENSE operates with a UV light source (1) which emits light that penetrates a gas sample in a measuring cell (2). Here light is partially absorbed by the gas molecules. Since each molecule has its own typical absorption spectrum, it is possible to simultaneously determine the concentration of different components of the gas. The remaining light is captured by the receiver (3). The receiver splits the light into narrow wavelength bands using an optical grating (4). Finally the light is captured by a CCD (5) and transformed into an electrical signal for processing. By adapting spectrometric technology to the analysis of biogas, its typical contaminants like VOCs, H₂S and NH₃, can be continuously monitored.