Quantitative characterization of deep fault-karst carbonate reservoirs: A case study of the Yuejin block in the Tahe oilfield

The Ordovician reservoirs in the Tahe oilfield are dominated by fractured-vuggy carbonate reservoirs, of which fault-karst reservoirs are a hot topic in recent years. Fault-karst reservoirs feature high production, large burial depth, and strong heterogeneity under the control of faulting and karstification. Based on geological, logging, and seismic data, this study classified the Ordovician fault-karst reservoirs in the Yuejin block of the Tahe oilfield into three types, namely karst-cave, dissolved-vug, and fractured types, and established the integrated identification criteria of the three types of reservoirs. This study characterized karst caves, dissolved vugs, and multi-scale faults through seismic wave impedance inversion and frequency-domain detection of multi-scale faults. 3D geological models of different types of reservoirs were built using the combined deterministic and stochastic methods and characterized the spatial distribution of multi-scale faults, karst caves, dissolved vugs, and physical property parameters of reservoir. This study established the method for the geological modeling of fault-karst reservoirs, achieved the quantitative characterization and revealed the heterogeneity of fault-karst reservoirs. The karst-cave and dissolved-vug types are high in porosity and act as reservoirs, while the fractured type is high in permeability and act as flow pathway. This study lays the foundation for the development index prediction, well emplacement, and efficient development of the fault-karst carbonate reservoirs.

Nickel-catalyzed Construction of Heat Conductive Network in Electrically Calcined Anthracite (ECA) Based Carbon Blocks

Nickel nitrate was introduced into carbon blocks by using ECA aggregates as catalyst-carrier.The Ni-containing anthracite aggregates were firstly prepared by mixing anthracite aggregates in nickel nitrate ethanol solution and then incorporated into carbon blocks after pre-treating.The phase composition,microstructure and properties of all carbon blocks fired at 1 000℃or 1 400℃in a coke bed were studied with the aid of an X-ray diffractomer,a field emission scanning electron microscope,a mercury porosimetry and a laser thermal conductivity meter.The results showed that the addition of Ni-containing anthracite aggregates promoted the formation of one-dimensional nanocarbon andβ-SiC whiskers at 1 000℃and the growth ofβ-Sialon at 1 400℃,respectively.Moreover,the cold compressive strength and microporosity characteristics of the carbon blocks with the addition of Ni-containing anthracite aggregates were enhanced and the thermal conductivity was remarkably improved attributing to the high heat conductive network formed by the ceramic phases.

Carbon matrix/SiNWs heterogeneous block as improved reversible anodes material for lithium ion batteries

A novel carbon matrix/silicon nanowires(SiNWs) heterogeneous block was successfully produced by dispersing SiNWs into templated carbon matrix via a modified evaporation induced self-assembly method. The heterogeneous block was determined by X-ray diffraction, Raman spectra and scanning electron microscopy. As an anode material for lithium batteries, the block was investigated by cyclic voltammograms(CV), charge/discharge tests, galvanostatic cycling performance and A. C. impedance spectroscopy. We show that the SiNWs disperse into the framework, and are nicely wrapped by the carbon matrix. The heterogeneous block exhibits superior electrochemical reversibility with a high specific capacity of 529.3 mAh/g in comparison with bare SiNWs anode with merely about 52.6 mAh/g capacity retention. The block presents excellent cycle stability and capacity retention which can be attributed to the improvement of conductivity by the existence of carbon matrix and the enhancement of ability to relieve the large volume expansion of SiNWs during the lithium insertion/extraction cycle. The results indicate that the as-prepared carbon matrix/SiNWs heterogeneous block can be an attractive and potential anode material for lithium-ion battery applications.

Blocking Behavior of Organic Solid Phase in the Carbon Dioxide Multiphase and Multicomponent Displacement Process

Better dealing with carbon issues can support the management of current greenhouse gas emissions while achieving energy economic diversification and energy security. Carbon dioxide displacement has become the most acknowledged and practical method in enhanced oil recovery system. This is because of its oil sweep efficiency and ability to reduce the level of greenhouse gas emission. Nevertheless, it would lead to the organic solid phase deposition, which causes the changes of the wettability and the damages of wellbores and reservoirs. In this study, we used slim tube test and component test to research the dynamic characteristics of displacement process. In addition, the mechanism of porous media blockage was also investigated. Results show that when the displacement pressure closed to the minimum miscibility pressure, reservoir blockage in pore throat could happen. Component test characterizes that during near miscible displacement process, the components of oil sample varied obviously, the variation range of peak component carbon marks fluctuated strongly. Crude oil component differentiation could happen after carbon dioxide fully contacted with oil. Besides, the rapid extraction mechanism of aromatic hydrocarbons played a significant role in this process under such condition. The reason is that the solubility of saturated hydrocarbons to asphaltene and non-hydrocarbons is obviously weaker than aromatic hydrocarbons. Controlling the pressure is considered as an important link to prevent the occurrence of blocking in the carbon dioxide multiphase and multicomponent displacement process.

基于阵列声波测井估算碳酸盐岩储层岩石力学和地应力参数——以顺北4号带为例

地质力学分析在油气藏勘探开发过程中发挥着重要作用,顺北油气田中—下奥陶统一间房组—鹰山组储层地应力研究相对滞后。对比分析了顺北4号带下古生界中—下奥陶统一间房组—鹰山组碳酸盐岩不同类型储层的岩石力学和地应力特征,同时探讨了微观颗粒结构对碳酸盐岩储层地应力和岩石力学参数的控制作用,为顺北地区超深层碳酸盐岩储层评价提供了基础地质依据。基于弹簧组合模型,通过岩石力学实验和阵列声波测井确定了岩石力学和地应力特征,通过铸体薄片和X射线CT扫描表征碳酸盐岩的微观孔隙结构。研究结果表明:顺北4号带一间房组—鹰山组杨氏模量分布在50~89 GPa,抗压强度在99~136 MPa,泊松比在0.25~0.32;地层最大水平主应力为200~225 MPa,最小水平主应力为125~160 MPa。一间房组—鹰山组碳酸盐岩不同类型储层的岩石力学参数和地应力存在明显差异,从Ⅰ类、Ⅱ类、Ⅲ类到非储层段碳酸盐岩的杨氏模量、抗压强度和最大水平主应力明显增大,而泊松比和最小水平主应力变化不大。相比于一间房组—鹰山组泥晶灰岩,砂屑-生屑灰岩方解石颗粒较大,颗粒黏结程度降低,导致岩石抗压强度和杨氏模量减小;砂屑-生屑灰岩部分方解石颗粒呈次圆状或圆状,颗粒三维空间球度较大,颗粒之间咬合作用减弱,使得岩石的抗压强度和杨氏模量减小;砂屑-生屑灰岩存在大量的孔隙和裂缝,灰岩易沿着潜在的微裂缝面或者颗粒接触面摩擦滑动甚至破裂,同样导致岩石抗压强度和杨氏模量减小。此外,一间房组—鹰山组泥晶灰岩受热液作用影响,部分白云石交代为石英,导致泥晶灰岩的抗压强度和杨氏模量增加。岩石的宏观力学特征和岩石力学参数受岩石微观颗粒结构的制约,一间房组—鹰山组杨氏模量、抗压强度和最大水平主应力低值区即为顺北4号带优势储层发育区带。

城市街区单元绿地空间格局与植物群落碳汇效益优化研究

【目的】目前城市绿地已经进入存量发展阶段,如何在城市有限绿地空间条件下实现“碳中和”目标,合理布局低碳绿地空间格局,科学配置植物群落以增加生物多样性,成为目前城市绿地碳汇效益研究的重点和难点。【方法】以西安市碑林区和沣西新城的城市绿地空间格局为研究对象,对研究区域内街区单元的绿地空间格局进行分析并分类,探索街区单元绿地空间格局与碳汇量化关系,并从平面布局和垂直结构两方面提出城市街区单元绿地碳汇效益的优化方法,并选取碳储量最低的单核心辐射型街区单元的3个绿地样方进行碳汇效益优化设计。【结果】总结出4种西安市典型城市街区单元绿地空间格局模式,明晰了碳储量分布特征以及绿地空间格局对碳储量的影响机制,提出了城市街区单元绿地空间格局碳汇效益优化方法,发现碳储量与斑块类型面积(CA)、景观形状指数(LSI)呈极显著正相关关系,与聚集度(AI)呈极显著负相关关系。各类绿地空间格局碳储量大小为多核心辐射型>散点分布型或廊道穿越型>单核心辐射型,建议在单核心辐射型街区单元优化中增加植物群落层次结构,并增加高固碳植物种类及数量,提升样方内年固碳量。【结论】从中观尺度讨论街区单元绿地空间格局与植物群落碳汇效益之间的关系,使城市中小尺度绿地发挥应有的生态系统服务功能,探索街区单元绿地空间格局的构成要素与设计方法,为低碳绿地设计提供参考,提升城市街区单元内社区生活圈的人居环境质量。

基于LCA的扭王字块物化阶段碳排放核算及减排措施

扭王字块作为量大面广的护堤结构,其碳排放的量化计算对于节能减排具有重要意义。基于LCA理论,将扭王字块物化阶段划分为原材料生产、原材料运输、构件制作、构件转运和现场施工5个阶段,采用碳排放系数法构建扭王字块物化阶段的碳排放测算模型,并以某大型护堤工程为例,演示计量扭王字块物化阶段碳排放的具体流程。结果表明:扭王字块物化阶段的碳排放主要来自原材料生产和运输;通过对比砂石材料不同运距和运输方式的碳排放量,得出就近取材和长距离采用铁路或水路运输可有效降低碳排放;对比公路运输不同燃料车辆的碳排放,汽油车和LNG车的碳排放低于柴油车。

微生物碳酸盐生产工厂的构成、特征及沉积学意义——以河南云梦山剖面为例

【目的】“碳酸盐(生产)工厂”研究强调生物群落对碳酸盐生产过程以及规模的调控和特异性影响,在深入认识碳酸盐岩成因和形成机制方面具有重要价值,是碳酸盐沉积学领域关注热点和重要方向。虽然该概念的正式提出已有二十多年历史,但如何从工厂角度解读地质历史时期,特别是深时特异性、大规模碳酸盐岩的发育过程和影响因素方面仍缺乏系统性认识。【方法】以河南云梦山剖面寒武系崮山组为例,利用多尺度、网格定量化评价方法对微生物碳酸盐生产工厂的样式、内部结构、建造过程等方面进行了详细阐述。【结果】研究区微生物碳酸盐生产工厂以底栖微生物群落为主要建造者,形成样式包括叠层石、凝块石、树枝石、均一石以及微生物诱导沉积构造(MISS)。伴生的颗粒类型包括鲕粒、球粒、生屑、竹叶状内碎屑和微生物岩角砾,主要分布于工厂建造格架间。微生物碳酸盐生产工厂发育具期次性,单期工厂发育规模较小(海底至水面高度不足1 m)但空间延伸广,包括半球状、穹窿状、板状等宏观形态;其内部结构包括少量单独的建造样式,以及广泛发育的垂向复合形式。【结论】通过分析影响工厂发育的各类因素,局限潮坪环境下较高的营养水平对微生物碳酸盐生产工厂的繁盛可能起到了主要作用,而古丈期总体海侵背景造成适宜微生物碳酸盐生产工厂发育的环境消失,导致工厂最终关闭。相关工作的开展提供了一个与现代澳大利亚Hamelin Pool微生物碳酸盐生产工厂非常相似的古代实例,对认识寒武纪碳酸盐生产工厂类型、特征和演化规律方面具有较好的参考价值。

ICP-AES法测定废电解铝阳极碳块中铁、锂、钾、钙、镁含量

废电解铝阳极碳块经过高温碳化,通过盐酸-硝酸-高氯酸三酸溶解完全后,冷却,完全溶解盐类加入10 mL 1.19 g/mL的盐酸,在优选出最优的仪器工作状态下,创建了ICP-AES法测定废电解铝阳极碳块样品中Fe、Li、K、Ca、Mg的化学分析方法。每个元素的校准曲线相关系数均大于0.999,同时对以上多种元素进行检出限、加标回收试验研究,结果表明其相对标准偏差(n=8)为0.60%~2.24%,加标回收率在97.1%~104%。

大庆油田海外多类型油藏高效开发配套技术

针对大庆油田海外多种类型油藏开发面临的挑战和技术需求,梳理近5 a大庆油田海外油藏开发形成的技术成果,系统总结已形成的适合海外多种类型油藏的特色高效开发技术。大庆油田经过近5 a来的海外油藏开发实践,将成熟油藏开发技术与海外油藏特征相结合,依靠已有优势技术创新驱动,形成了3项海外特色开发技术:一是以油藏精细描述和“优、分、调”立体开发调整为核心的复杂断块砂岩油藏有效开发技术;二是以化学剂研制及性能评价和化学驱试验方案优化为核心的高温高盐砂岩油藏化学驱提高采收率配套技术;三是以碳酸盐岩油藏测井精细评价、高渗透层识别和注水开发为核心的孔隙型碳酸盐岩油藏开发配套技术。海外油藏开发实践证明,大庆油田针对海外多类型油藏的高效开发配套技术,有力支撑了中国石油权益区块的高效开发,提升了大庆油田的国际知名度和影响力。

城区与街区尺度碳排放测算方法综述

随着中国2030年“碳达峰”和2060年“碳中和”远景目标的提出,碳排放研究将成为我国未来较长一段时间内的重要课题。城市规划作为实现减排降碳的重点领域,受到社会与学界的广泛关注。为了给规划领域碳减排相关研究提供参考,介绍了国内外城区和街区尺度碳排放测算方法,包括基于活动的碳排放测算技术、基于监测的碳排放测算技术以及其他碳排放测算技术,分析各方法的优劣势、适用尺度与适用对象,并阐述了国内外城区建筑碳排放测算模型在工程中的应用,探讨了现有碳排放测算方法存在的不足,提出未来城区尺度碳排放测算的改进建议,旨在为推进城市绿色低碳发展转型、实现“碳达峰”与“碳中和”目标提供支撑。

碳酸盐岩致密气成藏地质条件分析——以四川盆地大安区块茅一段为例

四川盆地大安区块大安2、大安1、大坝1井相继在茅一段石灰岩中获得天然气发现,由于勘探程度低,对天然气成藏地质条件认识不清。文中以该区茅一段为例,综合野外地质调查、单井分析,以及有机碳分析、薄片鉴定、X射线衍射、场发射扫描电镜等测试成果,开展烃源岩岩性、地球化学特征、储层沉积相、矿物组分、微观孔隙特征及含气系统研究,分析致密气成藏地质条件,建立成藏模式。研究结果表明:茅一段眼球、眼皮灰岩沉积受控于中缓坡沉积环境,构成了自生自储的物质基础;眼皮灰岩是一套有效烃源岩,提供充足的烃源供给;眼球、眼皮灰岩为低孔低渗致密储层,互层状叠置,纳米孔、微米孔发育,微裂缝贯通穿插,有利于大面积成藏;成藏模式为致密气源储一体、源内聚集、就近吸附,天然气动态生成,动态聚集,不易逸散;该区在燕山中晚期成藏,喜马拉雅期保存,中缓坡的眼皮灰岩带具有高脆性、中高TOC、中含气性特点,是致密气有利勘探方向。

A Sustainable Strategy for Spent Cathode Carbon Blocks Hazardous Waste Recycling Using Binary Molten Salt Thermal Treatment

Waste-to-Energy treatment is a promising path to environment and energy management in the future.This work detailed a binary molten salt thermal treatment methodology for the detoxification of spent cathode carbon block(SCCB)waste and the recycling of carbonaceous materials.The thermal behavior of SCCB and SCCB blended with molten salts was investigated.It was found that the NaCl-Na_(2)CO_(3)binary molten salts significantly contributed to reducing pyrolysis onset temperature by 334.3 K compared to that of SCCB itself(i.e.,activation energy of pyrolysis reaction was reduced from 4.24×10^(5)to 2.30×10^(5)J/mol),thus helping to lower thermal treatment energy consumption.With the addition of binary molten salts,the residue after thermal treatment in a horizontal tube furnace experiment was separated into two layers.The bottom-layer residue was mainly composed of molten salts.The fluorine content in the form of NaF and CaF_(2)of top-layer residue was reduced significantly while the carbon content remained unchanged.Specifically,the leaching concentration of fluoride ion was decreased from 4620 mg/L to 856 mg/L.It is noted that the NaF and CaF_(2)can be removed through water-leaching and hydrothermal acid-leaching methods and thus the carbonaceous materials with a calorific value of 17.5 MJ/kg were obtained.

400 kA铝电解槽异形阴极炭块对阴极电压降的影响

传统阴极炭块顶部是平坦的,阴极铝液流动时几乎没有阻力。使用表面凸起的阴极炭块进行研究,目的是增加铝电解槽中铝液流动的阻力,起到减波和减少铝液流动速度的作用,以此降低水平电流密度、阴极电压和铝液流速,保障铝电解槽生产安全稳定。通过COMSOL软件进行模拟,发现随着阴极炭块表面凸起块数的增加,阴极压降和水平电流密度均呈下降趋势,其中阴极压降最大降幅为39.8 mV,水平电流密度最大降幅为2087 A m^(2),并对某铝厂400 kA铝电解槽使用异形阴极炭块后进行测试,测试结果与模拟结果一致。

墙材用蒸压加气碳纤维增强混凝土砌块的性能分析

蒸压加气混凝土砌块具有轻质、多孔、保温、隔音和抗风等优点,被广泛用作墙体建筑、内部隔断、地基填充和保护等建筑材料中。然而,这种墙材大多存在强度低、吸水率大及容易开裂等不足,限制了其进一步发展。为改善上述缺陷,在蒸压加气混凝土中添加碳纤维,并研究了碳纤维添加量对蒸压加气混凝土力学性能的影响。试验发现,在蒸压加气混凝土中添加碳纤维可以减少蒸压加气混凝土的干燥收缩,提高其抗压强度和劈裂抗拉强度,改善其韧性。

高压浸出处理废旧阴极炭块回收石墨掺配制备铝用炭阳极

废旧阴极炭块作为铝工业仅次于赤泥的第二大固体废物,对于生态环境具有显著污染隐患,同时富含大量优质石墨资源,兼具循环利用属性。为实现废旧阴极炭块优质石墨资源的高效循环利用,利用高压浸出处理废旧阴极炭块,系统对比了废旧阴极炭块、煅后石油焦以及不同阶段回收石墨的理化性质差异,选取回收石墨掺配制备铝电解炭阳极。结果表明,相较于煅后石油焦,回收石墨具有较为接近的工业成分、物相组成及元素含量,但晶体结构和沥青润湿性存在显著差异。鉴于此,随着回收石墨掺配量的增加,制备阳极的使用性能逐渐降低。在低掺量条件下,废旧阴极炭块回收石墨具备掺配制备铝电解炭阳极的可行性和应用潜力。

城市生活街区餐饮环境空间低碳系统更新设计研究——以武汉粮道街为例

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