Measuring and Processing Biogas Produced in Laboratory-Scale Batch Reactors

In this work the upgrading of biogas into biomethane has been addressed by resorting to the use of the chemical capture of carbon dioxide. We started with the realization of a biodigestion systems used as source of biogas. With this system, we investigated either the production capacity of the different substrates and the main factors (temperature, pH and mixing of the substrate) which influence the biodigestion process. To make accurate measurements of the amount of biogas and biomethane produced, three types of different gas-meters, all based on the principle of liquid displacement, have been devised, assembled and compared. We have also evaluated three different types of gas flow calibrators, based on the principle of thermal mass flow sensing, constant differential pressure and mechanical displacement. At the end, we used the systems built to investigate the capture of carbon dioxide by ammonia in aqueous solution at room temperature and pressure where the volatilization of the ammonia has been limited by non-traditional methods.