油气管道漏磁数据处理和缺陷识别量化方法的研究进展

漏磁法是最稳定的无损在线检测技术之一,用于评估油气管道的健康状况。从通道基线校正、异常值判别、数据缺口的恢复和滤波四个方面阐述了漏磁数据预处理的方法和步骤;结合漏磁数据缺陷的峰谷值等显性特征,总结了不同特征提取方法下缺陷信号的本质特征;介绍了基于支持向量机、神经网络、图像处理和形态学等方法构建缺陷反演模型。最后,从数据预处理和缺陷识别量化两方面展望了漏磁信号处理未来的研究方向。

基于储层时变的水驱优势通道治理对策

海上某水驱油藏存在明显的水驱优势通道。水驱优势通道的形成,宏观上是流固耦合作用的结果,微观上主要表现为岩石骨架结构、孔喉半径及连通性等特征参数的变化。通过非线性拟合建立渗透率及相渗曲线端点与水驱通量的时变关系,并耦合到模型中,建立物性随时间变化的油藏物性时变模型。在此基础上,开展井间水驱优势通道治理对策研究,提出调剖段塞封堵优势通道、组合段塞深度调剖封堵多级优势通道、组合段塞深度调剖后有效接替驱替三种治理方式,并应用于矿场实践。结果表明,针对油通比低于0.001m-1的水驱优势通道区域,三项对策均可达到一定的治理效果。以调剖治理优势通道,建议首要封堵中部优势通道,并在保证经济性的条件下适当扩大封堵范围。针对不同级别优势通道的组合段塞深度调剖治理方式,相比单段塞调剖效果更优。治理优势通道后有效的接替驱替方式是发挥封窜潜力的关键,采用组合段塞深度调剖后转调驱,可达到相对最优的优势通道治理效果。

原油储罐泄漏检测技术研究

原油储罐在复杂的内外部环境中最容易出现的失效形式是底板穿孔从而导致原油泄漏。文章介绍了声发射方法和漏磁扫描方法应用于储罐底板的泄漏检测。两种方法都可以评估与定位底部材料的损伤及底板材料的微泄漏。文章介绍了原油储罐泄漏检测原理,分析了现场检测过程,对同一具原油储罐进行声发射和漏磁扫描检测后,对两种方法的检测结果进行分析与经济性对比,进而给出该储罐的完整性评估,并提出储罐的检修意见。

油气管道典型渐变缺陷的漏磁特征研究

基于漏磁检测技术,建立了油气管道典型渐变缺陷的有限元仿真模型,通过分析缺陷类型、几何尺寸对漏磁场的影响,进一步探究了缺陷截面形状特征参数与漏磁信号的对应关系,分析不同缺陷漏磁信号特征的变化规律,对于提高缺陷识别与量化的精度、丰富缺陷样本数据库至关重要。以梯形、阶梯形典型渐变缺陷为研究对象,通过开展仿真模拟研究,进一步探究梯形缺陷与阶梯形缺陷特征参数与漏磁信号的对应关系,为缺陷漏磁场的定性和定量分析提供参考。

Chemical composition, mechanism of antibacterial action and antioxidant activity of leaf essential oil of Forsythia koreana deciduous shrub

Objective: To identify the chemical constituents of leaf essential oil of Forsythia koreana(F. koreana) and evaluate its ef ects on bacterial strains. Methods: The essential oil of leaf of F. koreana was extracted by using hydrodistillation process and the volatile components investigated with the help of gas chromatography coupled with mass spectrometry. The antibacterial study was carried out with the help of agar disc dif usion method, MIC, MBC and viable count. The mode of action was determined with help of potassium ion l ux, cellular material release and scanning electron microscopy. The antioxidant activity was determined with the help of 2, 3-diphenyl-2-picrylhydrazyl method, nitric oxide scavenging activity and superoxide anion radical scavenging assay. Results: Total ten compounds were identii ed as trans-phytol(42.73%), cis-3-hexenol(12.95%), 毬-linalool(10.68%), trans-2-hexenal(8.86%), trans-2-hexenol(8.86%), myrcenol(3.86%), 4-vinylphenyl acetate(3.86%),(4Z)-4,6-heptadien-1-ol(3.18%), lemonol(2.73%) and benzeneacetaldehyde(2.27%) by gas chromatography coupled with mass spectrometry. The antibacterial study was demonstrated that leaf essential oil of F. koreana act against foodborne and other pathogenic bacteria. The mode of action revealed that this essential oil acted on the cytoplasmic membrane, resulting in loss of integrity and increased permeability. In addition, leaf essential oil of F. koreana was shown to be rich in linalool, which contributes to improved antioxidant activity. Conclusions: These results show that leaf essential oil of F. koreana has great potential as a natural food preservative, antibacterial and antioxidant agent.

Treatment of oil/water emulsion by polyethylene glycol ultrafiltration membrane

Polyethylene glycol(PEG) membranes with different molecular mass cut-offs were used to treat oil/water emulsion, and the effects of experimental conditions including pressure, temperature and different opera- ting modes on permeate flux and removal rate of chemical oxygen demand (COD_ Cr) were studied. The results show that the permeate flux of ultrafiltration membrane is influenced by pressure and temperature; practical pressure is chosen to be 0.30.7MPa for the PEG with molecular mass cut-offs of 8000 and 0.71.0 MPa for the PEG with molecular mass cut-offs of 2500; and the practical temperature is chosen to be 2532℃. Different operating modes of ultrafiltration also influence the permeate flux and removal rate of COD_ Cr. The ultrafiltration membrane of intermittent cross-flow operating mode is easier to be influenced by blocky polarization and contamination than that of sequential cross-flow operating mode. Removal rate of COD_ Cr in intermittent cross-flow and sequential cross-flow condition can be maintained at about 93%.

静电纺聚偏二氟乙烯纤维膜的制备及其在油水分离中的应用

选择性透过膜用于油水分离具有能耗低、装置简便、易操作、效率高的特点,其核心在于采用过滤效率高及使用寿命长的膜材.本文采用了高压静电纺丝工艺,以聚偏二氟乙烯(PVDF)为原料,制备一种超疏水、结构可调控的电纺PVDF膜(EPVDF膜).利用扫描电子显微镜(SEM)、傅立叶红外光谱(FTIR)、粉末X-射线衍射(XRD)、X-光电子能谱(XPS)等对EPVDF膜进行了形貌成份的表征,采用水接触角(WCA)对膜材表面特性进行了测试.结果表明,电纺PVDF膜的油水分离效率可达95%以上,对三种油水混合物均可实现30次以上的有效分离,其最大油通量可达到5 300 L/(m^(2)·h).

Geological emission of methane from the Yakela condensed oil/gas field in Talimu Basin, Xinjiang, China

A static flux chamber method was applied to study natural emissions of methane into the atmosphere in the Yakela condensed oil/gas field in Talimu Basin, Xinjiang, China. Using an online method, which couples a gas chromatography/high-temperature conversion/isotope ratio mass spectrometry (GC/C/MS) together, the 13C/12C ratios of methane in the flux chambers were measured. The results demonstrated that methane gases were liable to migrate from deep oil/gas reservoir to the surface through microseepage and p...

Atmospheric Dry Deposition in the Proximity of Oil-Fired Power Plants at Mexican Pacific Coast

Dry deposition samples were collected in a weekly basis during 2010 in a site located at the Mexican Pacific Coast: Manzanillo, Colima. Samples were collected with an automatic wet/dry deposition sampler using nylon filters as surrogate surfaces. Samples were extracted with deionized water and analyzed for pH, conductivity, Na+, K+, Ca2+, Mg2+, NH4-, NO3-, SO42- and Cl-. Nitrate and sulfate were the most abundant ions, contributing with 53% to the total ionic mass;and their levels exceeded the hemispheric background concentrations proposed for marine remote sites. The influence of the power plants burning combustoleo located upwind the sampling site was completely evident. From meteorological analysis, it could be observed that the sampling site was all time under the influence of power plants as a result of the effect of breezes. However, in spite of the high levels of NO3- and SO42- found in the samples collected, pH value average was almost neutral, with 28% of samples slightly acid. Potassium was the most abundant cation and from the quantification of the neutralization effect of the main alkaline components, the prevalence role of K+ was completely evident, suggesting the influence of the mining complex Pe?a Colorada located upwind the sampling site, where amyl xanthate potassium is used as collector in tailing dams. Dry deposition fluxes were estimated for all ions measured. Nitrogen dry deposition at Manzanillo is already in the upper extreme of the threshold value reported for sensible ecosystems. On the other hand, sulfur deposition exceeded slightly the critical load value reported for some ecosystems in Europe. Even at this moment, nitrogen and sulfur deposition is not a problem, it is necessary to take steps to avoid that total deposition of these elements exceeds critical loads, considering that results reported in this study not include the wet deposition fluxes.

Daily Variation of Natural Emission of Methane to the Atmosphere and Source Identification in the Luntai Fault Region of the Yakela Condensed Oil/Gas Field in the Tarim Basin,Xinjiang,China

The static flux chamber method was applied to study natural emissions of methane to the atmosphere in the Luntai fault region of Yakela Condensed Oil/Gas Field in the Tarim Basin, Xinjiang Municipality, northwestern China. Using an online method, which couples together a gas chromatography/high-temperature conversion/isotope ratio mass spectrometry （GC/C/MS）, 13^C/12^C ratios of methane in flux chambers were measured and showed that methane gases are liable to migrate from deep oil/gas reservoirs to the surface through fault regions and that a part of the migrated methane, which remains unoxidized can be emitted into the atmosphere. Methane emission rates were found to be highest in the mornings, lowest in the afternoons and then increase gradually in the evenings. Methane emission rates varied dramatically in different locations in the fault region. The highest methane emission rate was 10.96 mg/m^2·d, the lowest 4.38 mg/m^2, and the average 7.55 mg/ m^2·d. The 13^C/12^C ratios of the methane in the flux chambers became heavier as the enclosed methane concentrations increased gradually, which reveals that methane released from the fault region might come from thermogenic methane of the deep condensed oil/gas reservoir.

海底冷泉渗漏油气泡原位定量测定--以墨西哥湾GC600为例

海洋环境中冷泉渗漏是甲烷等有机化合物和其他温室气体进入海洋和大气的重要来源。准确定量确定冷泉渗漏的甲烷气泡通量对于评估它们对全球甲烷预算和气候变化有着重要的研究意义。采用高分辨率视频成像系统原位观察了墨西哥湾GC600冷泉渗漏区Mega Plume 2喷口,并获得了油气泡连续释放的视频片段。通过采用半自动气泡计数算法估算了Mega Plume 2喷口释放的油气泡个数及其释放速率。而通过图像处理技术确定了Mega Plume 2释放的油气泡的大小和尺寸分布。Mega Plume 2混合喷口释放的油气泡平均直径2.56mm±1.01mm,油气泡释放速率为80.25个·秒^(-1)。Mega Plume 2喷口年释放通量为177.7m^(3)·a^(-1)(19.55~106.62t·a^(-1))。然而,Mega Plume 2喷口的气泡释放速率与潮汐无关,可能与其他因素如水合物,油气藏增压及沉积层差异加载有关。只有对冷泉渗漏系统开展长期的原位在线观察,我们才能准确获取冷泉渗漏系统活动特征及其释放通量。

高通量、抗污染油水分离膜的研究进展

膜分离是深度处理含油废水的有效技术之一,对生态环境保护,提高资源利用率,实现“双碳”目标具有重要意义。开发分离效率高、运行稳定性强的高性能膜材料是油水分离膜研制的热点。综述了近年来油水分离膜在渗透性能和抗污染性能强化方面的研究进展,重点对膜性能强化的机制进行讨论,并分别从传质机制和抗污染机制角度对强化策略进行归纳总结。最后,提出了高性能油水分离膜材料开发存在的问题,对未来的油水分离膜材料的研制方向进行了展望。

渤海溶解CH_(4)分布和通量的季节变化及其影响因素

甲烷(CH_(4))是影响地球辐射平衡的主要温室气体,海洋是大气CH_(4)的自然源,而陆架等近海是释放CH_(4)的热点海域。于2021年4月、7月和10月对渤海进行了调查,以认识其分布特征并估算其海-气交换通量。春、夏和秋季表层海水CH_(4)浓度分别为(4.56±2.60)、(8.31±4.01)和(4.99±1.31)nmol/L,夏季明显高于春秋季。CH_(4)的垂直分布规律为底层普遍高于表层,不同站位的垂直分布空间差异较大。渤海CH_(4)分布主要受河流输入、油气泄漏、生物活动以及沉积物-水界面交换等因素的影响,其中黄河向渤海输入CH_(4)约为每月1.4×104~2.8×10^(5)mol,秋冬季沉积物-水界面CH_(4)交换通量范围为-4.0~0.42μmol/(m^(2)·d),表明秋冬季沉积物既可能是渤海水体CH_(4)的源,也可能是其汇。春、夏和秋季渤海CH_(4)海-气交换通量分别为(1.1±2.4)、(7.5±8.8)和(3.9±5.5)μmol/(m^(2)·d)。渤海年CH_(4)排放通量为2.37×10-3 Tg/a,约占全球海洋释放总量的0.05%,远高于其面积占比0.02%,是大气CH_(4)的净源。该文系统探讨了渤海CH_(4)的分布特征及其影响因素,为深入认识近岸海域对全球海洋CH_(4)释放的贡献提供了科学依据。

地磁作用下油气管道力磁耦合仿真分析与实验研究

选取X80输油气管道作为研究对象,建立相应的磁力学模型,通过理论与实验的方法,研究地磁场环境下复杂应力-磁通量的变化规律。首先,通过COMSOL有限元仿真软件建立了X80管道模型,用Mises应力表征输油气管道不同内压荷载作用下的应力值,设置地磁场强度为50μT的背景磁场,对输油气管道模型施加不同的内压荷载,通过软件计算分析,得出输油气管道壁上磁通量信号的分布情况。然后,通过对地磁场环境下输油气管道应力-磁通量耦合实验进行分析,得出管道壁上磁通量信号随复杂应力的变化情况,并对实验数据进行分析处理。结果表明:在地磁场环境下,输油气管道的复杂应力在增大的过程中,其对应的磁通量信号也在增强,两者呈线性相关。同时,通过实验进一步验证了理论模型与仿真结果的可靠性。

基于漏磁内检测的管道焊缝缺陷识别及应对策略研究

漏磁内检测作为焊缝缺陷排查最有效的方法,因焊缝缺陷种类多、评价与修复标准体系复杂,亟须进行研究。基于油气管道漏磁内检测原理和焊缝特点,总结了焊缝、焊缝缺陷的分类及漏磁信号特征,梳理了焊缝缺陷在设计、施工验收、失效评价、响应及修复方面的标准规范,为在役管道焊缝缺陷评价与修复提供参考,也为焊缝缺陷隐患排查及油气管道安全运行提供技术支持。

基于无监督机器学习的流场分级方法研究——以D油田为例

目前我国大量老油田已进入特高含水期,储层在水驱过程中形成流场,流场内注入水存在大量的无效循环,驱油效率低,正确的流场评价成为高含水油藏挖潜措施之一。针对高含水油田长时间注入水冲刷导致储层物性时变这一现象,引入水相驱替通量,建立储层渗透率及相对渗透率随水相驱替通量变化的渗流模型,形成时变数值模拟技术。在考虑驱替效率及注入水冲刷程度的基础上,提出以油通比作为指标对流场进行分级评价。引入无监督机器学习算法,采用轮廓系数对分类数进行优选,确定流场分级的最佳分级类别及边界,克服人为主观影响。将建立的时变数值模拟及无监督机器学习流场分级方法应用于D油田,在确定流场分级的基础上,进一步制定产液结构调整策略,可有效提高油田采收率3.44个百分点。该方法为高含水油田流场评价及优势通道刻画提供了一种新思路。

纳米分子筛在天然动植物油淬火介质中的应用

主要测试对比了猪油、棕榈油、高油酸葵花籽油、菜籽油、葵花籽油、大豆油和亚麻籽油等多种天然动植物油的冷却特性和氧化安定性。结果表明,相比于矿物油和具有类似化学结构的合成酯,部分动植物油在冷却过程中没有蒸汽膜,该性能将有利于提高工件在淬火过程中的均匀性。同时针对该现象,进一步从不同油品的化学组成和淬火冷却过程中的热流密度变化等方面,从原理上阐述了产生此特殊现象背后的原因。另外尝试合成了一种新型的无机纳米分子筛,用于提高高油酸葵花籽油的热氧化安定性,结果表明纳米分子筛可能是传统酚类或胺类抗氧剂的一种更加环境友好的替代方案。

煤制油废水MBR膜污堵及清洗研究

以某煤制油废水MBR处理系统为例,本文主要介绍了煤制油废水处理工艺流程、MBR膜系统设计及运行状况。对本项目MBR膜污堵状况进行了研究,结果表明本项目主要膜污堵为悬浮固体污堵和有机胶体污堵。基于项目实际,设计了独立的离线清洗系统对MBR膜进行清洗,清洗后膜通量恢复情况良好,达到了系统要求。

基于水成膜泡沫叠加灭火法的油烃池火处置效能试验

为检验水成膜泡沫(AFFF)叠加灭火法的可行性,通过油烃池火扑救试验,分别对比不同风向和泡沫流量下AFFF叠加灭火法的灭火效能,油池燃烧过程由热成像设备实时记录。结果表明:相较于非AFFF叠加的灭火方法,AFFF叠加灭火法处置油池火的整体效能较高,符合油池火扑救要求。AFFF叠加灭火法具备如下优势:对泡沫灭火剂通用性强,灭火所需的低倍数、中倍数AFFF均可使用低倍数AFFF原液调制;具有良好的灭火性能,能够克服AFFF热稳定性不足的缺陷、提升AFFF的覆盖效果;能够提升泡沫延展性,使泡沫叠层达到油池远端的铺展覆盖。该灭火战术对处置燃烧面积较大的平面流淌火灾具有积极意义。

磁通屏障对潜油电机转矩特性的影响

转矩脉动是影响内置式潜油电机的重要因素,通过对电机转子内部磁通屏障的设计,进而达到降低转矩脉动的目的。以10极12槽内置式“一”字型潜油电机为基础模型,使用有限元法对潜油电机转子进行了二维瞬态场分析。基于磁通屏障效应对潜油电机气隙径向磁密的影响,得出了潜油电机转子在各种运转工况条件下的径向电磁特性分布的状况,并分别比较研究电机的齿槽转矩和电磁转矩等转矩特性。优化后,潜油电机的转矩脉动有了显著的降低。最后,采用砝码法验证磁通屏障的设计对潜油电机齿槽转矩具有较好的抑制效果。由于潜油电机的定子结构被限制,磁通屏障的优化设计具有非常大的意义。