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文章结合大港油田井下作业现场特点,通过研究井控装置FZ18-35防喷器在试压过程中存在的"原试压堵塞器不适合350型采油树井口四通"的具体问题,改进研制适合FZ18-35防喷器与350型采油树井口四通配套的ST18-35试压堵塞器来解决井控装置的现场试压问题,确保现场井控装置的完好,有效降低井控风险以及井喷事故污染环境的风险。 相似文献
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Jeffrey M. Novak Donald W. Watts 《Journal of environmental science and health. Part. B》2013,48(5):609-621
Abstract The effects of well bore volume removal (Vn) on the concentration of alachlor [2‐chloro‐N‐(2,6‐diethylphenyl)‐N‐(methoxy methyl) acetamide] and prometon (6‐methoxy‐N,N'‐bis(1‐methylethyl)‐1,3,5‐triazine‐2,4‐diamine] in ground water obtained from three monitoring wells installed in the Coastal Plain region of North Carolina was investigated. Seasonal effects were also investigated by conducting the exercise in February and May. In the majority of cases, the lowest pesticide concentrations occurred in the initial well bore volume (V1 = stagnant water). Removal of additional well bore volumes (V2 to V10) from two of the wells resulted in pesticide concentrations that did not vary substantially. This indicates that a representative aquifer sample was obtainable, in most cases from these wells, after removal of the initial well bore volume. In contrast, a third well required the purging of two well bore volumes before a stable alachlor concentration was achieved. Seasonal effects of bore volume removal vs. pesticide concentrations for the three wells were not significant (P > 0.05). It was concluded that a protocol for improved accuracy in pesticide analyses of ground water can be obtained by establishing a pesticide concentration‐purging (well bore volume) relationship for each well. 相似文献
175.
采用分层采样技术对场地地下水污染物进行三维空间描述 总被引:1,自引:0,他引:1
地下水单一混合层采样所需建井及采样技术较简单,曾被广泛应用于地下水监测,但根据该技术所得地下水污染物数据进行污染场地地下水污染羽和污染程度描述,常常存在较严重的偏差。以某氯代烃污染场地为例,详细阐述了巢式监测井的建井及分层采样技术,并以该场地主要污染物氯乙烯和氯仿为例,对比了来自不同采样技术的两个主要污染物数据,证实了采用分层采样技术对污染场地地下水进行调查,具有更好的准确性和可靠性。 相似文献
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监测井在化工厂区土壤和地下水污染监测中的应用 总被引:2,自引:0,他引:2
文章分析了监测井在化工厂区土壤和地下水污染监测中的应用 ,指出对化工厂区土壤和地下水污染进行有效监测的必要性 ,并探讨化工厂区监测井的整体规划和设计。 相似文献
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Finding the location and concentration of contaminant sources is an important step in groundwater remediation and management. This discovery typically requires the solution of an inverse problem. This inverse problem can be formulated as an optimization problem where the objective function is the sum of the square of the errors between the observed and predicted values of contaminant concentration at the observation wells. Studies show that the source identification accuracy is dependent on the observation locations (i.e., network geometry) and frequency of sampling; thus, finding a set of optimal monitoring well locations is very important for characterizing the source. The objective of this study is to propose a sensitivity-based method for optimal placement of monitoring wells by incorporating two uncertainties: the source location and hydraulic conductivity. An optimality metric called D-optimality in combination with a distance metric, which tends to make monitoring locations as far apart from each other as possible, is developed for finding optimal monitoring well locations for source identification. To address uncertainty in hydraulic conductivity, an integration method of multiple well designs is proposed based on multiple hydraulic conductivity realizations. Genetic algorithm is used as a search technique for this discrete combinatorial optimization problem. This procedure was applied to a hypothetical problem based on the well-known Borden Site data in Canada. The results show that the criterion-based selection proposed in this paper provides improved source identification performance when compared to uniformly distributed placement of wells. 相似文献
180.
将非洗井法采样筛管部位取样的可行性和洗井前后样品代表性作对比,当监测井中地下水流量为0.1 L/min~0.5 L/min时,用微扰动采样器在非洗井情况下采样。洗井前后常规无机离子浓度和5种物理指标的研究对比结果显示,在非洗井情况下用微扰动地下水采样器在筛管部位取样的样品与洗井之后的样品十分接近。6口监测井水中无机离子含量单方向方差分析结果显示,p值0.05(显著性),验证概率FF crit,表明在95%的置信度上可总结为无机化学参数在洗井前后无显著性差异。 相似文献