Abstract
A study on the anaerobic digestion of wheat straw in a pilot scale bioreactor with an organic load of 2, 5, 7, 10 and 20 g/l and a process duration of 18 to 80 days was performed. The pilot bioreactor used has a computerized system for control and monitoring of various operational parameters – temperature, pH, biogas composition, etc. Total solids, total organics and volatile fatty acids were measured by standard methods and gas chromatography. Daily biogas yield and its main components (CH4, CO2, H2S) were analysed too. During the anaerobic digestion, different species of microorganisms have been isolated from the genera Bacillus, Pseudomonas, Enterococcus and Aeromonas, as well as the species Terribacillus halophilus. With a known pathogenic potential are described Pseudomonas sp., Enterococcus sp. and Aeromonas sp. Studies on the antimicrobial resistance of all isolated strains show resistance to ampicillin, amoxicillin, bacitracin, ceftriaxone, gentamicin and vancomycin. The cellulose degrading activity of some of the bacterial isolates, their pathogenic potential and antimicrobial resistance are discussed in detail in the light of the data on the mechanisms of proven resistance.
Highlights
Anaerobic digestion (AD) of organic wastes is a very attractive biotechnology during the last years mainly in the field of the renewable energy sources and biofuels
In this study the co-digestion of cattle dung and wheat straw is the first stage for adaptation of the bacterial community to work only with wheat straw
This adaptation was obtained only with two experiments: - First experiment was carried out with organic load of 18,093 g/l (10% of wheat straw) - cumulative biogas production of 18,78 dm3 for 14 days was gained and at the last day of the experiment - CH4 = 51%, CO2 = 39%, and H2S ≥ 1000 ppm. - The second experiment was performed with organic load of 18,13 g/l (20 % of wheat straw)
Summary
Anaerobic digestion (AD) of organic wastes is a very attractive biotechnology during the last years mainly in the field of the renewable energy sources and biofuels. Тhe recent article describes briefly the new pilotscale biogas plant with computerized monitoring and control system of the Stephan Angeloff Institute of Microbiology – Bulgarian Academy of Sciences (SAIM-BAS). This biogas plant will be very useful for development of new optimised technologies for anaerobic digestion and co-digestion of different organic wastes and for multidisciplinary studies of this kind of processes (microbiological and biochemical studies, mathematical modelling with parameter and states estimation, sophisticated control algorithms development, new software sensors development, etc.)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
