Production of biogas from crude glycerol using ultrasound as pretreatment in a batch reactor
Lis Geraldine Zschach
Ramiro José Espinheira Martins
Global energy supply is based on petroleum derivative. Scarcity of natural sources and environmental concerns are problems associated to the energy supply as well as its increasing demand. These problems can be solved by using more renewable sources. Biofuels as biogas have the potential to provide energy and decrease environmental emissions. Studies made before, says that crude glycerol from biodiesel production process can be used to produce biogas by anaerobic digestion process. To improve biogas volume and its quality, pretreatments to the substrate are being studied. The aim of this work is to study the effect of ultrasound, a mechanical pretreatment, in crude glycerol to produce biogas. The volume of biogas and methane produced was measured, the last to evaluate the quality of biogas, to assess the main effect of pretreatment on anaerobic digestion. They were carried out in batch reactors under mesophilic conditions (37°C). Different pretreatment times with ultrasound (15 and 30 minutes) of glycerol treatment were tested and compared with untreated glycerol. For biogas production, measurement was made by moving with its pressure the plunger of a syringe.