Rock fracture grouting with microbially induced carbonate precipitation
Rock fracture grouting with microbially induced carbonate precipitation
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微生物诱导碳酸盐沉淀的岩石裂隙灌浆
DOI：
10.1002/2016wr018884
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发表时间：
2016-11
影响因子：
5.4
通讯作者：
J. Minto;Erica Maclachlan;Gráinne El Mountassir;R. Lunn
中科院分区：
文献类型：
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作者：
J. Minto;Erica Maclachlan;Gráinne El Mountassir;R. Lunn
微生物诱导碳酸盐沉淀已被提出用于土壤稳定、土壤加固和降低渗透率，作为传统水泥和化学灌浆的替代。在这篇文章中，我们评价了细孔岩石裂隙的灌浆，用尿素水解沉淀的碳酸钙，用巴氏芽孢杆菌。碳酸钙在小规模和近场规模(3.1m2)的人工裂缝中沉淀，由粗糙的岩石下表面和透明的聚碳酸酯上表面组成。利用延时照相法对碳酸钙沉淀的空间分布进行了成像，并通过示踪剂传输成像揭示了其对流动路径的影响。在大型试验中，水力孔径从276μm减小到22−m，相当于在恒流条件下12天的时间内，透过率降低了1.71×10−5到8.75×10−9m2/S。使用改进的注射策略，在3天的时间内，透过率降低了类似的三个数量级。碳酸钙在整个人工裂缝上析出，对上下表面都有很强的粘附性，通过控制注入流体的速度来控制析出，以防止注入井堵塞。这些实验表明，微生物诱导的碳酸盐沉淀可以成功地在不断流动的条件下灌浆裂缝，当需要高水平的水力密封时，它可能是一种可行的水泥基灌浆，当需要更耐用的灌浆时，它可能是一种可行的化学灌浆。
Microbially induced carbonate precipitation has been proposed for soil stabilization, soil strengthening, and permeability reduction as an alternative to traditional cement and chemical grouts. In this paper, we evaluate the grouting of fine aperture rock fractures with calcium carbonate, precipitated through urea hydrolysis, by the bacteria Sporosarcina pasteurii. Calcium carbonate was precipitated within a small‐scale and a near field‐scale (3.1 m2) artificial fracture consisting of a rough rock lower surfaces and clear polycarbonate upper surfaces. The spatial distribution of the calcium carbonate precipitation was imaged using time‐lapse photography and the influence on flow pathways revealed from tracer transport imaging. In the large‐scale experiment, hydraulic aperture was reduced from 276 to 22 μm, corresponding to a transmissivity reduction of 1.71 × 10−5 to 8.75 × 10−9 m2/s, over a period of 12 days under constantly flowing conditions. With a modified injection strategy a similar three orders of magnitude reduction in transmissivity was achieved over a period of 3 days. Calcium carbonate precipitated over the entire artificial fracture with strong adhesion to both upper and lower surfaces and precipitation was controlled to prevent clogging of the injection well by manipulating the injection fluid velocity. These experiments demonstrate that microbially induced carbonate precipitation can successfully be used to grout a fracture under constantly flowing conditions and may be a viable alternative to cement based grouts when a high level of hydraulic sealing is required and chemical grouts when a more durable grout is required.