Optical Probe

Optical probe designed specifically to measure samples within an anaerobic digester using optical spectroscopy. This will result in a significant advantage over the commercially available multi-purpose optical probes, since it will be designed to produce the best possible signal depending on the measuring conditions of the sample inside the anaerobic digester: slurry dark samples being stirred at medium temperature. As a consequence, it will be best choice for measuring inside digesters, but also it will be possible to be used in process with similar conditions.

Software application for AD control

The second result from the project will be the software application that will implement AD-Control Model – Model 1 as an easy tool for biogas plants to control their day to day operation. This will be a unique software application based on the measurements of SVFAs. Since these measurements have never been done online before, this software will be the very first to implement a control system using those measurements. The software will regulate the feed rate of digesters according to their value of SVFA. As mentioned, the use of this application will prevent automatically overloads in the anaerobic process and will save several chemical analysis per year to biogas plants.

Software application for SVFA concentration’s measurement

The third result will be the software application that will implement SVFAM Model – Model 2 as an easy tool to predict the concentration of single volatile fatty acids (SVFAs) through their spectra. This application will be based on the calibration model developed in the project and will be an important improvement in the field for its possibility to give an accurate measure of SVFAs in few minutes, compared to days or even weeks when outsourcing analysis to traditional laboratories.

Integrated system for measurement of SVFA and AD control

The fourth result will be the integrated system that will comprise the three previous results mentioned. Then, it will be the complete system to be installed in a biogas plant: the optical probes within the digesters to capture the signal; the multi-point spectrometer that will convert that signal into a spectrum able to be processed; the application using SVFAM Model – Model 2 that will convert that spectrum into the right value of SVFAs in the digester and finally, the software application implementing AD-Control Model – Model 1, that according to that value will decide the right feed rate for the digesters. Then, this complete system will allow an accurate, reliable and precise control of biogas plants, using an online measurement system never applied before, able to detect and prevent overloads in digesters and regulate the feed rate to have them in the desired situation 24/7.