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目的解决长庆油田某作业区集输系统的结垢问题。方法采用离子色谱仪等仪器对水样的理化性质进行测试分析,采用X射线衍射仪对现场垢样进行成分分析,通过室内静态结垢实验结合滴定法,研究油井采出液混合的配伍性,并对阻垢剂进行筛选及评价。结果长庆油田某作业区集输系统结垢的主要原因为该区C6和Y9两个层系的采出液不配伍,主要结锶钡垢,且结垢量较大。温度对总结垢量的影响较小,但随着两种水样的质量比接近1︰1时,结垢量达到最大。选择加注C型阻垢剂,且加注质量浓度为90 mg/L时,阻垢率可达86.1%,比原方案提高30%左右,阻垢后最大结垢量由1678 mg/L降为233 mg/L。结论现场提供的C型阻垢剂对长庆油田某作业区集输系统具有适用性,阻垢率高,能够有效减缓现场结垢问题。 相似文献
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《环境质量管理》2018,27(4):65-72
The most common problems in water distribution systems are corrosion and scaling, which cause both economic and customer health problems. The aim of the present study is to report the relationship between Urmia Lake's drying and the corrosion and scaling potential of groundwater used as drinking water during the spring and summer of 2015. Groundwater samples were collected from all of the catchments of the Urmia Lake basin, and the characteristics of the water were used to determine the corrosive and scaling indices using the Langelier Saturation Index and the Ryznar Stability Index. The results showed that the total dissolved solids measurement of the samples collected from the islands of Urmia Lake was higher than the maximum value of the standard level. In addition, the hardness in 36% of the zones was higher than that of the maximum suggested level. The concentration of calcium was lower than that of the standard, but the rest of the parameters were in the standard level range. Also, the results showed that the water of the Urmia Lake basin tends to be very scaling and corrosive. In order to control the corrosion and scaling caused by groundwater drawn from the catchments around Urmia Lake, measures should be taken to prevent Urmia Lake's drying and to manage the groundwater around this area. It is also suggested that a laboratory study regarding the condition of the distribution system be carried out to adjust the effective parameters, such as the pH. 相似文献
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采用电感耦合等离子体质谱(ICP-MS)和电感耦合等离子体发射光谱(ICP-OES)分析测试黔川三个不同原产地的19个典型白酒样中的48个元素含量组成。对多元素含量进行多维尺度分析(MDS)、方差分析(ANOVA)、主成分分析(PCA)和判别分析(DA)等多变量统计分析,探讨多元素组成对不同原产地白酒溯源的可行性,筛选出白酒原产地判定的有效指标。结果显示,不同原产地白酒样中多元素含量有其各自的分布特征,其中Ca、Na、Fe、Mn、Be、Sc、V、Cu、Ga、Ge、Y、Cs、Pr、Nd、Sm、Eu、Gd、Tb、Dy、Ho、Tm、Yb和Lu等23个元素存在显著差异。多维尺度分析和主成分分析将白酒样分成不同类别,其类别与原产地基本一致。通过逐步判别分析,筛选出6个元素指标可判别白酒样的产地来源,依次为Mn、Ga、Sc、V、Na和Cs,整体正确判别率为94.7%。利用多元素指纹技术对白酒原产地判定是可行的。 相似文献
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基于共词分析的复杂网络研究现状分析 总被引:1,自引:0,他引:1
以CNKI总库上有关复杂网络的相关文献为数据源,在共词分析的基础上通过多维尺度分析方法和战略坐标分析方法探析复杂网络在我国的研究现状及发展趋势,为从事复杂网络研究的学者提出参考.结果表明:①复杂网络的研究可分为两类,一类是复杂网络的理论研究,另一类是复杂网络的管理和安全方面的研究,这两个研究领域联系不紧密.②复杂网络的理论研究涉及复杂网络拓扑统计性质、演化机制与稳定性等,该领域整体联系比较紧密,研究趋向成熟.复杂网络管理、安全类团内部结构松散,研究尚不成熟,但与复杂网络中其他研究结合紧密,有进一步的发展空间.③在复杂网络的理论研究方面,与复杂系统、加权网络、拓扑结构、同步、稳定性、神经网络相关的研究领域可能成为今后研究的热点领域;在复杂网络管理、安全方面,SNMP将有可能成为热点研究项目. 相似文献
56.
吉林油田注水系统管线结垢严重,影响正常生产安全.为了解决结垢问题,对吉林油田注入水和结垢产物进行了分析,并给出了防护对策.结果表明:吉林油田注入水含有大量的HCO3-,Ca2+含量较其他成垢离子含量高;结垢产物主要是CaCO3垢,另有部分MgCO3垢、硅铝酸盐垢和铁垢,垢样具有明显的有机物包裹特征.在此基础上运用化学溶度积和化学反应方程式直观地表示了吉林油田注水系统的结垢机理.吉林油田注入水中碳酸盐的浓度积远大于其溶度积,导致大量碳酸盐析出结垢.注入水中携带有黏土,在管壁沉积形成硅铝酸盐结垢.铁腐蚀导致吉林油田注水系统产生少量铁垢.最后通过室内静态防垢性能测定法从3种常用缓蚀阻垢剂中筛选出适合吉林油田现场水质防腐阻垢的TH-907型缓蚀阻垢剂,在TH-907药剂质量浓度为50 mg/L时,阻垢效果最好. 相似文献
57.
Abstract: The important role of humans in the development of current ecosystems was recognized decades ago; however, the integration of history and ecology in order to inform conservation has been difficult. We identified four issues that hinder historical ecological research and considered possible solutions. First, differences in concepts and methods between the fields of ecology and history are thought to be large. However, most differences stem from miscommunication between ecologists and historians and are less substantial than is usually assumed. Cooperation can be achieved by focusing on the features ecology and history have in common and through understanding and acceptance of differing points of view. Second, historical ecological research is often hampered by differences in spatial and temporal scales between ecology and history. We argue that historical ecological research can only be conducted at extents for which sources in both disciplines have comparable resolutions. Researchers must begin by clearly defining the relevant scales for the given purpose. Third, periods for which quantitative historical sources are not easily accessible (before AD 1800) have been neglected in historical ecological research. Because data from periods before 1800 are as relevant to the current state of ecosystems as more recent data, we suggest that historical ecologists actively seek out data from before 1800 and apply analytic methods commonly used in ecology to these data. Fourth, humans are not usually considered an intrinsic ecological factor in current ecological research. In our view, human societies should be acknowledged as integral parts of ecosystems and societal processes should be recognized as driving forces of ecosystem change. 相似文献
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Community-based approaches to fisheries management has emerged as a mainstream strategy to govern dispersed, diverse and dynamic small scale fisheries. However, amplifying local community led sustainability outcomes remains an enduring challenge. We seek to fill a theoretical gap in the conceptualization of ‘scaling up community-based fisheries management’. We draw on literature of agriculture innovations to provide a framework that takes into account process-driven and structural change occurring across multiple levels of governance, as well as different phases of scaling. We hypothesize that successful scaling requires engagement with all aspects of a governing regime, coalescing a range of actors, and therefore, is an enterprise that is larger than its parts. To demonstrate where the framework offers value, we illustrate the development of community-based fisheries management in Vanuatu according to the framework’s main scaling dimensions. 相似文献