Chemical Engineering Department, University of Cordoba, Campus Universitario de Rabanales, Ctra. N-IV, Km 396, Building Marie Curie (C-3), 14071, Córdoba, Spain.
Department of Biochemistry and Molecular Biology, University of Cordoba, Campus Universitario de Rabanales, Ctra. N-IV, Km 396, Building Severo Ochoa, 14071, Córdoba, Spain.
Environ Res. 2020 Nov;190:110057. doi: 10.1016/j.envres.2020.110057. Epub 2020 Aug 14.
The objective of this study is to evaluate comparatively the odor removal efficacy of two biofilters operated under different conditions and to identify taxonomically the microbial communities responsible for butyric acid degradation. Both biofiltration systems, which were filled with non-inoculated wood chips and exposed to gas streams containing butyric acid, were evaluated under different operational conditions (gas airflow and temperature) from the physical-chemical, microbiological and olfactometric points of view. The physical-chemical characterization showed the acidification of the packing material and the accumulation of butyric acid during the biofiltration process (<60 days). The removal efficacy was found to be 98-100% during the first 20 days of operation, even at high odor concentration. Changes in the operational temperature increased the odor load factor from 400 to 1400 ou/m·s, which led to the reduction of microbiota in the packing material, and a drastic drop of the odor removal efficacy. However, the progressive increase in gas airflow improved the biodegradation efficacy of butyric acid up to 88% with odor loadings as high as 33,000 ou/m, while a linear relationship between odor inlet load and removal capacity was also found. The analysis of the microbial community showed that Proteobacteria was the most abundant phylum along the biofiltration time (58-92%) and regardless of the operational conditions. Finally, principal component analysis applied to the physical-chemical and microbiological data set revealed significant differences between the two biofilters under study.
本研究的目的是比较评价两种生物过滤器在不同条件下的除臭效果，并鉴定负责丁酸降解的微生物群落的分类学特征。两个生物过滤系统均填充未接种的木屑，并暴露于含有丁酸的气流中，从物理化学、微生物学和嗅闻的角度评估不同操作条件（气体流速和温度）下的性能。物理化学特性表明，在生物过滤过程中（<60 天）包装材料酸化且丁酸积累。在操作的前 20 天，即使在高气味浓度下，去除效率也达到了 98-100%。操作温度的变化将气味负荷因子从 400 增加到 1400 ou/m·s，这导致包装材料中的微生物群减少，除臭效率急剧下降。然而，气体流速的逐步增加提高了丁酸的生物降解效率，高达 88%，即使在高达 33,000 ou/m 的气味负荷下也是如此，同时还发现气味入口负荷与去除能力之间存在线性关系。微生物群落的分析表明，在生物过滤过程中（58-92%），变形菌门是最丰富的门，且与操作条件无关。最后，主成分分析应用于物理化学和微生物数据集揭示了研究中的两个生物过滤器之间存在显著差异。
