Stamps Blake W, Bojanowski Caitlin L, Drake Carrie A, Nunn Heather S, Lloyd Pamela F, Floyd James G, Emmerich Katelyn A, Neal Abby R, Crookes-Goodson Wendy J, Stevenson Bradley S
Department of Microbiology and Plant Biology, University of Oklahoma, Norman, OK, United States.
UES, Inc., Dayton, OH, United States.
Front Microbiol. 2020 Feb 25;11:167. doi: 10.3389/fmicb.2020.00167. eCollection 2020.
Renewable fuels hold great promise for the future yet their susceptibility to biodegradation and subsequent corrosion represents a challenge that needs to be directly assessed. Biodiesel is a renewable fuel that is widely used as a substitute or extender for petroleum diesel and is composed of a mixture of fatty acid methyl esters derived from plant or animal fats. Biodiesel can be blended up to 20% v/v with ultra-low sulfur diesel (i.e., B20) and used interchangeably with diesel engines and infrastructure. The addition of biodiesel, however, has been linked to increased susceptibility to biodegradation. Microorganisms proliferating via degradation of biodiesel blends have been linked to microbiologically influenced corrosion in the laboratory, but not measured directly in storage tanks (i.e., ). To measure microbial proliferation, fuel degradation and microbially influenced corrosion, we conducted a yearlong study of B20 storage tanks in operation at two locations, identified the microorganisms associated with fuel fouling, and measured corrosion. The bacterial populations were more diverse than the fungal populations, and largely unique to each location. The bacterial populations included members of the , and Proteobacteria. The abundant Eukaryotes at both locations consisted of the same taxa, including a filamentous fungus within the family , not yet widely recognized as a contaminant of petroleum fuels, and the family of yeasts. Increases in the absolute and relative abundances of the were correlated with significant, visible fouling and pitting corrosion. This study identified the relationship between fouling of B20 with increased rates of corrosion and the microorganisms responsible, largely at the bottom of the sampled storage tanks. To our knowledge this is the first study of this scale incorporating community and corrosion measurements in an active biodiesel storage environment.
可再生燃料对未来有着巨大的潜力，但它们易受生物降解及随后腐蚀的影响，这是一个需要直接评估的挑战。生物柴油是一种可再生燃料，被广泛用作石油柴油的替代品或添加剂，由源自植物或动物脂肪的脂肪酸甲酯混合物组成。生物柴油可与超低硫柴油按体积比20%混合（即B20），并可与柴油发动机及基础设施互换使用。然而，生物柴油的添加与生物降解敏感性增加有关。在实验室中，通过生物柴油混合物降解而增殖的微生物与微生物影响的腐蚀有关，但尚未在储油罐中直接测量（即 ）。为了测量微生物增殖、燃料降解和微生物影响的腐蚀，我们对两个地点运行的B20储油罐进行了为期一年的研究，确定了与燃料结垢相关的微生物，并测量了腐蚀情况。细菌种群比真菌种群更多样化，且在每个地点基本都是独特的。细菌种群包括 、 和变形菌门的成员。两个地点丰富的真核生物由相同的分类群组成，包括 科内的一种丝状真菌，它尚未被广泛认为是石油燃料的污染物，以及酵母科。 的绝对丰度和相对丰度的增加与明显可见的结垢和点蚀腐蚀相关。这项研究确定了B20结垢与腐蚀速率增加之间的关系以及主要在采样储油罐底部造成这种情况的微生物。据我们所知，这是首次在活跃的生物柴油储存环境中进行的这种规模的研究，纳入了群落和腐蚀测量。
