The evaluation and the development of three devices
for measurement of biogas production
O. El Asri1*, M. Mahaouch1, M.E. Afilal1
1Mohamed First University, Faculty of Sciences, Laboratory biology of plants and microorganisms,
BP 524, 60000 Oujda, Morocco.
* Corresponding author. Email: firstname.lastname@example.org
Received: 29 July 2014; revised version accepted: 26 November 2014
We evaluate in this paper, three biogas measurement devices which are mostly used in laboratory for Anaerobic digestion. The measurement with our device had the maximum biogas production (223; 327; 174 Nml/g OM) for the three tested concentrations. This estimation is more reliable because it was based on the interaction of several results. It was not like any absorption of biogas into the gas holder. The gradual shift of care solution reduces the pH decrease by reducing the dissolution of CO2 in the digestive. The kinetics in this device showed a progressive acclimatization of the methanogens to the bioreactor, consequently the accumulation of organic acids has been transitory which prevents installation of the inhibition. The biodegradation reaches a high value (43, 8 %) which confirms a good performance. For the device which uses a gasometer by displacement of water. The measures low potentials of biogas (99; 133; 190 Nml/g OM). This measurement system is consequently not recommended because the gasometer absorbs a significant fraction of the produced biogas. The device measures biogas by pressure shows several deficiencies. Quick inhibition of methanisation, accumulation of organic acids, dissolution of CO2 in the product and decreased of pH the values below norms to inhibitory values. Consequently, we recommend that researchers in the field of methanisation using our device for accurate measurement of biogas produced. Thus, technical and methodological point of view, this is an inexpensive, easy use in laboratory and robust.
Keywords: Anaerobic digestion; Biogas; Device; Gasometer and methanisation.