油页岩地下原位转化与钻采技术现状及发展趋势

我国油页岩地质资源量巨大,是保证我国能源安全的重要战略资源。油页岩地下原位转化开采是油页岩工业的发展趋势,在系统收集相关资料、数据和调研的基础上,总结了国内外油页岩原位转化技术的发展历程,提出了高效加热技术、储层改造技术和地下空间封闭技术三个油页岩原位转化核心技术,并对这三大核心技术的主要技术特点和发展现状做出了进一步分析。在明确油页岩地下原位转化开采低成本、高产量和低污染的目标基础上,提出了地表井下协同加热-多阶段物理化学复合加热-自生热驱动链式原位裂解的热流体原位复合加热技术、双水平井小井距电磁测距导向技术、多工艺精确储层改造压裂技术、注浆帷幕和气驱止水地下空间封闭技术等油页岩原位转化核心技术的发展方向,以期对我国油页岩地下原位转化开采技术提供借鉴和参考。     

油页岩大规模原位开采数值模拟研究及开采参数讨论

为了研究原位裂解过程中不同规模井组温度场和生烃量的差异,分别对六边形井组数量为7个、19个、37个和61个四种情况油页岩原位开采生产模型进行了建模,以吉林省扶余县油页岩开采试验区为试点区,在使用ANSYS软件的Mesh模块对模型进行加密网格化的基础上,使用Fluent进行了流体场和温度场模拟;通过求解化学反应动力学方程组进行了油页岩生烃过程模拟,并进行了不同井间距、注气速率和双裂缝间距情况下的模拟。模拟结果表明,大规模油页岩原位开采过程中油页岩生烃主要分为三个阶段,即快速生烃阶段(注热前500d)、缓慢生烃阶段(注热500～1 500d)和平稳阶段(注热1 500～3 000d)。增加井组数量可以提高热烟气对中心加热区域的热利用效率。但增加井组数量对单井组生烃量和能源回报率的增幅逐步减小,当井组数量从37个增加到61个时,加热为3 000d时的单井组生烃量增率小于3.1%,能源回报率增率小于8.7%,因此进行油页岩原位开采时选取37个或37以上的井组数量为获得高能源回报率的最佳方案。在61个井组条件下,不同开采参数模型达到最大能源回报率的开采参数为井间距30m、注气速率12m/s和裂缝...     

油页岩原位开采地下冷冻墙缓冲距离研究

油页岩原位高温开采,需要在矿区周边建立地下冷冻墙以阻止地下水的流入,防止油气的泄漏。油页岩的高温开采区与地下冷冻墙的冷冻区之间的缓冲距离影响油岩页的开采效果及地下冷冻墙的制冷效果,也影响整个工程的施工成本及运行费用。采用理论计算、数值模拟分析的方法,以最低成本为目标,对合理的缓冲距离进行了详细计算与分析,确定出了合理的缓冲距离,为油页岩高温开采地下冷冻墙的设计提供了理论指导。     

油页岩开采模式

随着世界石油市场高油价时代来临,原来高成本的油页岩生产变得经济,油页岩已成为非常重要的替代能源。由于受诸多因素限制,常规油页岩开采方法成本较高。基于我国油页岩埋藏条件及其物理力学性质,分析国内外非常规油页岩开采以及相关的试验,提出了2种开采模式——油页岩原位开采与钻孔水力开采。     

油页岩原位开采生烃过程数值模拟及井位讨论

为研究流体加热技术下油页岩生烃量随时间变化的规律,并找出更适合油页岩原位开采的井位,笔者使用流体模拟软件ANSYS对多井注热和单井注热两种方案,正三角形、正方形和正六边形井组共6种模式建模,进行了温度场模拟。通过MATLAB软件求解油页岩生烃的化学反应动力学方程得到对应时间下的油页岩原位开采的生烃量,并比较不同井位方案的投入产出结果。模拟结果表明,油页岩的生烃量随注热时间的增加而增大,增速先快后慢,注热36个月后增长效果已不明显。多井注热方案下生烃效果优于单井注热,油页岩生烃的净值最大时为六井模式的第20个月,为1 141. 85 t;其次是四井模式的第25个月,为1 034. 63 t;最后为三井模式的第22个月,为878. 95 t。在单井注热模式下,净值最大时刻在第33个月,为390. 00 t。多井注热模式下各模式的能源回报率分别为2. 73、1. 74和2. 05,单井注热模式下能源回报率为1. 418。     

松辽盆地扶余—长春岭矿区青山口组油页岩原位开采中试示范区优选

随着松辽盆地地下原位转化技术点试实验的成功,亟需从中试和生产角度寻找适合油页岩规模开采的靶区,建立油页岩原位选区的参数体系是开展上述工作的首要任务。在众诚集团和吉林大学油页岩原位转化实验经验基础上,从油页岩品质、矿床赋存特征角度出发,提出油页岩含油率、有机质类型及成熟度、厚度、岩石组合特征、埋深、横向稳定性和地层倾角是进行原位选区的关键参数。基于松辽盆地东南隆起区扶余—长春岭矿区基础数据,确定1号和2号矿层为油页岩原位开采有利层位,并通过原位开采潜力值在研究区选出4个适合油页岩原位开采的中试示范区。运用体积法计算松辽盆地扶余—长春岭矿区适合原位开采的油页岩油资源为36 995×10~4t。     

油页岩原位开采温度-时间-转化率判识方法及应用

油页岩原位转化开采加热的最终温度、加热时间和最终油气转化率与原位开采的经济成本息息相关。利用Rock-Eval 6型岩石热解分析仪分别获取不同升温速率下的油页岩烃产率-转化率和烃产率-活化能之间的关系,以烃产率为桥梁,建立活化能与转化率的对应关系;在此基础上,依据化学动力学反应原理,将油页岩有机质（干酪根）演化生成油气的过程近似为具一级反应特征的热裂解反应,获取不同转化率条件下温度倒数（1/T）与时间对数（ln t）的关系式,建立油页岩原位转化温度-时间-转化率关系图。以广东茂名盆地油柑窝组油页岩为例,通过上述方法建立了油页岩原位转化开采温度-时间-转化率关系图。由判识关系图可知：加热至350℃开采该区油页岩,转化率达90%需要98 a;加热至200℃开采该区油页岩,在不采取其他措施的情况下即使转化10%也需要147 a。实际情况下,地下油页岩原位受热具有非均质性,加热开采能耗大,通过添加催化剂降低油页岩原位油气转化所需的温度、改善油气产物品质可能是油页岩原位开采技术的一种发展方向。     

降水井改造为原位生产井的工艺设计及应用

为有效地扩大油页岩原位开采区域和节约油页岩原位开采的成本,需将废置的降水井改造成为原位生产井。根据降水井与原位生产井井身结构的相似性,对农安油页岩原位开采先导试验工程基地的降水井改造工艺进行了设计和优化。同时研发了偏心轮式套管割管装置及三爪式套管打捞装置用于拔管施工。工程实践证明,该工艺具有步骤简单、合理、高效以及价格低廉等特点。偏心轮式套管割管装置及三爪式套管打捞装置应用在降水井改造中,均取得理想的效果。     

农安油页岩水力压裂模拟及实验研究

裂隙的数量和尺寸会影响油页岩原位开采的成本与效率,开采前需对油页岩进行水力压裂来建立或扩展裂隙,而压裂过程中的破裂压力是一个重要的参数。以农安矿区油页岩为研究对象,数值计算了其射孔完井下的水力压裂的破裂压力并采用真实破裂过程分析软件（二维渗流分析版）对水力压裂过程进行数值模拟,得到油页岩破裂压力。同时对该矿区油页岩压裂进行了实验对比,验证了数值模拟的有效性。对比结果表明模拟值、实验值较计算值均偏大。     

不同边界条件对油页岩原位转化开采的影响及启示

借助于烃源岩生排烃模拟技术,开展了加热温度、加热速率、恒温时间、水质量分数等不同边界条件对油页岩原位转化开采影响的模拟实验。结果表明:升高转化温度、降低升温速率、延长恒温时间均有利于提高原位转化出油率和改善油品;流体压力过度升高对油品稍有改善,但出油率有所降低,且过高的流体压力(如超过开采层上覆岩层压力)会对地面工程产生破坏影响;高温地层水可能作为催化剂、反应物和溶剂参加反应,促进非共价键的断裂,提高出油率。在此基础上,提出了在干馏转化过程中加入额外的供氢物质或高温水中加入适量的水溶性催化剂提高油页岩原位转化开采出油率的方法。     

The terrestrial fauna of the Late Triassic Pant-y-ffynnon Quarry fissures,South Wales,UK and a new species of Clevosaurus (Lepidosauria: Rhynchocephalia)

Pant-y-ffynnon Quarry in South Wales yielded a rich cache of fossils in the early 1950s, including articulated specimens of new species (the small sauropodomorph dinosaur Pantydraco caducus and the crocodylomorph Terrestrisuchus gracilis), but no substantial study of the wider fauna of the Pant-y-ffynnon fissure systems has been published. Here, our overview of existing specimens, a few described but mostly undescribed, as well as freshly processed material, provides a comprehensive picture of the Pant-y-ffynnon palaeo-island of the Late Triassic. This was an island with a relatively impoverished fauna dominated by small clevosaurs (rhynchocephalians), including a new species, Clevosaurus cambrica, described here from a partially articulated specimen and isolated bones. The new species has a dental morphology that is intermediate between the Late Triassic Clevosaurus hudsoni, from Cromhall Quarry to the east, and the younger C. convallis from Pant Quarry to the west, suggesting adaptive radiation of clevosaurs in the palaeo-archipelago. The larger reptiles on the palaeo-island do not exceed 1.5?m in length, including a small carnivorous crocodylomorph, Terrestrisuchus, and a possible example of insular dwarfism in the basal dinosaur Pantydraco.     

The effect of water on accessory phase solubility in subaluminous and peralkaline granitic melts

The solubilities of columbite, tantalite, wolframite, rutile, zircon and hafnon were determined as a function of the water contents in peralkaline and subaluminous granite melts. All experiments were conducted at 1035 °C and 2 kbar and the water contents of the melts ranged from nominally dry to approximately 6 wt.% H₂O. Accessory phase solubilities are not affected by the water content of the peralkaline melt. By contrast, solubilities are affected by the water content of the subaluminous melt, where the solubilities of all the accessory phases examined increase with the water content of the melt, up to 2 wt.% H₂O. At higher water contents, solubilities are nearly constant. It can be concluded that water is not an important control of accessory phase solubility, although the water content will affect diffusivities of components in the melt, thus whether or not accessory phases will be present as restite material. The solubility behaviour in the subaluminous and peralkaline melts supports previous spectroscopic studies, which have observed differences in the coordination of high field strength elements in dry vs. wet subaluminous granitic glasses, but not for peralkaline granitic glasses. Lastly, the fact that wolframite solubility increases with increasing water content in the subaluminous melt suggests that tungsten dissolved as a hexavalent species.     

Quaternary stresses revealed by calcite twinning inversion: insights from observations in the Savonnières underground quarry (eastern France)

Calcite samples were extracted both from the rock matrix and the superficial coating of a karstified fault plane of an underground quarry, located in the eastern border of the Paris basin. The karstification is dated as Quaternary. Analysis of mechanical calcite twinning reveals that only the calcite matrix has also undergone a compression trending WNW that can be attributed to the Mio-Pliocene alpine collision. Both coating and matrix have undergone a strike-slip regime with σ₁ roughly trending north–south, that could correspond to the regional present-day state of stress, a strike-slip compression rather trending NNW, modified by local phenomena. To cite this article: M. Rocher et al., C. R. Geoscience 335 (2003).     

HYDROGEOLOGY

正20141756 Chen Ruige(Mathematical College,China University of Geosciences,Beijing100083,China);Zhou Xun Numerical Simulation of Groundwater Level Fluctuation in a Coastal Confined Aquifer with Sloping Initial Groundwater Level Induced by the Tide(Geological Bulletin of China,ISSN1671-2552,CN11-4648/P,32(7),2013,p.1099-1104,6 illus.,16 refs.) Key words:confined water,groundwater level     

METAMORPHIC PETROLOGY

正20141408 Cai Jia(Institute of Geology,Chinese Academy of Geological Sciences,Beijing100037,China);Liu Fulai Petrogenesis and Metamorphic P-T Conditions of Garnet-Spinel-Biotitebearing Paragneiss in Danangou Area,Daqingshan-Wulashan Metamorphic Complex Belt(Acta Petrologica Sinica,ISSN1000-0569,CN11-1922/P,29(7),     

SERIALS

正~~     

GEOPHYSICAL EXPLORATION

正20142386An Guoying(China Aero Geophysical Survey and Remote Sensing Center for Land and Resources,Beijing 100083,China)Application of Satellite Remote Sensing in Regional Hydrogeological Investigation:Taking Cenozoic Strata in Wenquan Sheet(1∶250 000)of Karakoram Range as an Example(Geosci-     

QUATERNARY GEOLOGY & GEOMORPHOLOGY

正20141016An Chengbang(Key Laboratory of Western China’s Environmental Systems,Ministry of Education,Lanzhou University,Lanzhou 730000,China);Zhao Yongtao Lake Records during the Last Glacial Maximum from Xinjiang,NW China and Their Climatic Impli-     

PETROLEUM GEOLOGY

正20141538 Cao Qing(School of Earth Sciences and Engineering,Xi’an Petroleum University,Xi’an 710065,China);Zhao Jingzhou Characteristics and Significance of Fluid Inclusions from Majiagou Formation,Yichuan Huangling Area,Ordos Basin(Advances in Earth Science,ISSN1001-8166,CN62-1091/P,28(7),2013,p.819-828,7 illus.,3 tables,43 refs.)     

GEOCHEMISTRY

正20142002 Wei Hualing(Institute of Geophysical and Geochemical Exploration,Chinese Academy of Geological Sciences,Langfang065000,China);Zhou Guohua Element Content and Mineral Compositions in Different Sizes of Soil in Tongling Area,Anhui Province(Geological Bulletin of China,ISSN1671-2552,CN11-4648/P,32(11),2013,p.1861