Biofiltration of methane from cow barns: Effects of climatic conditions and packing bed media acclimatization. (August 2018)

• Record Type: Journal Article
• Authors: Fedrizzi, Franciele; Cabana, Hubert; Ndanga, Éliane M.; Cabral, Alexandre R.
• Is Part Of: Waste management. Volume 78(2018)
• Page Start: 669
• Page End: 676
• Publication Date: 2018-08
• Subjects: Biofiltration -- Packing bed media -- Acclimatization -- Cooling-warming cycles -- Animal houses; Hazardous wastes -- Periodicals; Refuse and refuse disposal -- Periodicals; 363.728
• DOI: 10.1016/j.wasman.2018.06.038
• Languages: English
• ISSNs: 0956-053X

Abstract

Graphical abstract: Highlights: Biofilters efficiently abate CH4 emissions from cow barns under winter conditions. CH4 removal rates in a biofilter may withstand temperature oscillations over time. Easily available materials in agricultural context can be used as packing bed media. Appropriate acclimatization process of the packing bed media is essential. Abstract: The performance of biofiltration to mitigate CH4 emissions from cow barns was investigated in the laboratory using two flow-through columns constructed with an acclimatized packed bed media composed of inexpensive materials and readily available in an agricultural context. The biofilters were fed with artificial exhaust gas at a constant rate of 0.036 m 3 h −1 and low inlet CH4 concentration (0.22 g m −3 = 300 ppm). The empty-bed residence time (EBRT) was equal to 0.21 h. Additionally, in order to simulate temperature changes under natural conditions and determine the influence of such cycles on CH4 removal efficiency, the upper part of the biofilters were submitted to temperature oscillations over time. The maximum oxidation rate (1.68 μg CH4 gdw −1 h −1 ) was obtained with the commercial compost mixed with straw. Accordingly, it was considered as packing bed media for the biofilters. The CH4 removal efficiency was affected by the temperature prevailing within the biofilters, by the way in which the cooling-warming cycles were applied and by the acclimatization process. The shorter the cooling-warming cycles, the more oxidation rates varied. With longer cycles, CH4 removal rates stabilized and CH4 removal efficiencies attained nearly 100% in both biofilters, and remained at this level for more than 100 days, irrespective of the temperature at the top of the biofilter, which was – at times – adverse for microbiological activity. The first order rate constant for CH4 oxidation kinetics of the entire system was estimated at 15 h −1 . If such rate could be transposed to real field conditions in Canada, home to nearly 945, 000 dairy cows, biofiltration may be applied to efficiently abate between 2 × 10 6 and 3 × 10 6 t yr −1 of CO2 equivalent (depending on how estimates are performed) from bovine enteric fermentation alone.