Effect of CO_(2)flooding in an oil reservoir with strong bottom-water drive in the Tahe Oilfield,Tarim Basin,Northwest China

The dissolution and diffusion of CO_(2)in oil and water and its displacement mechanism were investigated by laboratory experiment and numerical simulation for Block 9 in the Tahe oilfield,a sandstone oil reservoir with strong bottom-water drive in Tarim Basin,Northwest China.Such parameters were analyzed as solubility ratio of CO_(2)in oil,gas and water,interfacial tension,in-situ oil viscosity distribution,remaining oil saturation distribution,and oil compositions.The results show that CO_(2)flooding could control water coning and increase oil production.In the early stage of the injection process,CO_(2)expanded vertically due to gravity differentiation,and extended laterally under the action of strong bottom water in the intermediate and late stages.The CO_(2)got enriched and extended at the oil-water interface,forming a high interfacial tension zone,which inhibited the coning of bottom water to some extent.A miscible region with low interfacial tension formed at the gas injection front,which reduced the in-situ oil viscosity by about 50%.The numerical simulation results show that enhanced oil recovery(EOR)is estimated at 5.72%and the oil exchange ratio of CO_(2)is 0.17 t/t.

Achieving asymmetric redox chemistry for oxygen evolution reaction through strong metal-support interactions

Water electrolysis poses a significant challenge for balancing catalytic activity and stability of oxygen evolution reaction(OER)electrocatalysts.In this study,we address this challenge by constructing asymmetric redox chemistry through elaborate surface OO–Ru–OH and bulk Ru–O–Ni/Fe coordination moieties within single-atom Ru-decorated defective NiFe LDH nanosheets(Ru@d-NiFe LDH)in conjunction with strong metal-support interactions(SMSI).Rigorous spectroscopic characterization and theoretical calculations indicate that single-atom Ru can delocalize the O 2p electrons on the surface and optimize d-electron configurations of metal atoms in bulk through SMSI.The^(18)O isotope labeling experiment based on operando differential electrochemical mass spectrometry(DEMS),chemical probe experiments,and theoretical calculations confirm the encouraged surface lattice oxygen,stabilized bulk lattice oxygen,and enhanced adsorption of oxygen-containing intermediates for bulk metals in Ru@d-NiFe LDH,leading to asymmetric redox chemistry for OER.The Ru@d-NiFe LDH electrocatalyst exhibits exceptional performance with an overpotential of 230 mV to achieve 10 mA cm^(−2)and maintains high robustness under industrial current density.This approach for achieving asymmetric redox chemistry through SMSI presents a new avenue for developing high-performance electrocatalysts and instills confidence in its industrial applicability.

Recurrence anomaly of ground water behavior before strong earthquakes in North China

By analyzing the relationship between ground water behavior and strong seismic activity during the past more than 20 years in North China, we have found similar water level descending variation of a part of wells in the short-term stage before several strong earthquakes. The characteristics of anomaly are: at the beginning, water level dropped abruptly or accelerated to drop; then it turned to slow rising with a smaller amplitude than that of descending; earthquakes occurred during the slow-rising process of water level, and at that time or before earthquake occurrence, water level rose with a large amplitude. Among more than 100 wells in North China, the descending anomalies were not recorded for many times, but similar variation processes of water level were noted at different wells before several strong earthquakes, which proves that seismic precursory anomalies of ground water are of certain recurrence features, occurring repeatedly before different strong earthquakes. Therefore, it is necessary to study the genesis of this type of anomaly and its relationship with strong seismic activity.

Analysis of Factors Influencing Shut in Pressure Cone in Offshore Strong Bottom Water Reservoir

X oilfield is an offshore strong bottom water reservoir with water cut up to 96% at present, and liquid extraction has become one of the main ways to increase oil production. However, the current liquid production of the oilfield reaches 60,000 m3/d due to the limitation of offshore platform, well trough and equipment, the oilfield is unable to continue liquid extraction. In order to maximize the oil production of the oilfield, it is necessary to study the strategy of shut in and cone pressure. Through numerical simulation, this paper analyzes the influence of different factors, such as crude oil density, viscosity, reservoir thickness, interlayer, permeability and so on, on the drop height of water cone and the effect of precipitation and oil increase after well shut in. At the same time, the weight of each factor is analyzed by combining the actual dynamic data with the fuzzy mathematics method, and the strategy of well shut in and cone pressure is formulated for the offshore strong bottom water reservoir. It provides the basis and guidance for the reasonable use of shut in pressure cone when the reservoir with strong bottom water meets the bottleneck of liquid volume.

Identification of Interlayer in Strong Bottom Water Reservoir and Its Influence on Development Effect

X oilfield is located in Bohai Sea area, in which G oil formation is a typical drape anticline structure, which is composed of multiple sets of thick sandy conglomerate and multiple sets of argillaceous intercalation. From the perspective of development effect, muddy interlayer has a great impact on the oilfield. In this paper, through core identification and well logging identification, the electrical discrimination standard is summarized to identify the interlayer. Through statistics and analysis of the production performance of actual wells, the influence of muddy interlayer on the development performance of oil wells is summarized. This study provides guidance for the development of strong bottom water reservoirs with interlayer.

Analysis on the Characteristics of the Coseismic Response of Water Levels Recorded in Three Wells in Hainan,China to the Two Sumatra-Andaman Strong Earthquakes

The characteristics of seismic water level fluctuations of the two Sumatra-Andaman strong earthquakes with magnitude 8.7 and 8.5 on December 26,2004 and March 29,2005 recorded at Jiaji well,Qionghai,Hainan were analyzed,the features of the infrequent "step" changes of well water level after the two earthquakes were also analyzed and the mechanism of the "step change" of well water level was discussed.Then the high-sample-rate digital observation data of seismically-induced water level fluctuations of the Sumatra-Andaman strong earthquakes with magnitude 8.7 and 8.5 recorded at Nanbin well,Sanya and Tanniu well,Wenchang were analyzed.The results suggest that the dominant period of the seismic well water level fluctuation in all three wells was comparatively accordant,the amplitudes of seismic water level fluctuation of the same earthquake in different wells were clearly different,the time duration of seismic water level fluctuations of different earthquakes at the same well was also clearly different.

强涌潮水流条件下直立圆柱体的涌潮作用力试验研究

为厘清强涌潮河口直立式圆柱体受到的涌潮作用力与涌潮水流条件、圆柱直径的关系,通过涌潮水槽模型试验研究了三种直径直立圆柱在不同潮前水深、涌潮高度条件下的涌潮作用力。结果表明,强涌潮的涌潮作用力为直立圆柱受到冲击力叠加该时刻的水流绕流阻力、圆柱前后水位压差力。通过数据回归分析,得到了一个无量纲涌潮作用力计算公式。该公式表明,涌潮作用力分析计算除了要考虑涌潮高度、圆柱直径外,潮前水深也是关键因素,且涌潮作用力与圆柱直径之间存在显著的非线性关系。

胜利油田强水敏性稠油储层高温变化特征分析——以王庄油田和金家油田为例

强水敏性稠油油藏在热采开发过程中受到高温作用影响,储层发生一系列变化。为明确其变化特征,对胜利油田具强水敏性的王庄油田和金家油田热物理模拟等实验后矿物、微观孔喉结构、物性等变化进行了对比,并进行了异同性分析。强水敏性稠油储层变化的相似性主要体现在:当温度低于150℃时,蒙脱石晶间距较大,溶蚀、转化程度弱,膨胀性较强,使孔隙结构复杂,渗透性变差;当温度高于150℃后,高温抑制蒙脱石膨胀,转化、溶蚀增强,产生较大溶蚀孔隙,改善孔隙结构,增大连通性,储层渗透性变好;其差异性主要体现在高温溶蚀颗粒对储层的影响上,温度为150℃时,王庄油田溶蚀颗粒浓度最高,浓度变化总体是先增后减,随着周期的增加而减少,颗粒对储层的影响小,而金家油田颗粒浓度随温度升高而大幅增加,堵塞孔喉,油井普遍存在供液不足的现象,因此,王庄油田主要开发矛盾为强水敏,而金家油田的主要开发矛盾除了强水敏外,还有强速敏。

准噶尔盆地东部北10井区中深层稠油CO_(2)非混相驱油技术

准噶尔盆地东部北10井区头屯河组油藏具有埋藏深、原油黏度大、储层强水敏的特点,自探明以来一直未获得有效动用。为了解决油藏难动用的难题进行了CO_(2)-稠油实验,在实验结果的基础上,根据试验区生产现状提出“非混相驱+吞吐”措施,利用数值模拟手段优化生产参数得到最优方案并预测出生产指标。结果表明:地层稠油注入CO_(2)后原油体积膨胀和黏度降低的能力大幅增强,是提高采收率的主要机理;井区稠油CO_(2)驱替方式为非混相驱,驱替过程中CO_(2)先以溶解和扩散作用为主,待建立驱替通道后才开始产出原油,采收率为29.60%;试验区非混相驱初期见效慢,为加快受效提出“油井吞吐”措施,数值模拟预测非混相驱配合3轮油井吞吐生产,最终采收率可达21.0%,解决了研究区油藏难动用的难题。研究成果对中深层强水敏稠油油藏的动用具有一定的借鉴意义。

不同浸种及催芽处理对明日叶种子萌发的影响

明日叶(Angelica keiskei)是一种经济价值极高、开发前景广阔的食药两用蔬菜.然而由于土壤及温湿度条件等因素限制,明日叶种子出苗率低,制约明日叶的栽培生产.以山东新产的绿茎明日叶种子为材料,通过不同水温浸种及不同浓度KNO_(3)、植物激素、强氧化剂的外源添加,研究了提高种子的萌发处理方法.结果表明,温水(55℃)浸种、KNO_(3)溶液、植物激素、强氧化剂处理均可不同程度地促进种子萌发.与清水浸种相比,在KNO_(3)溶液处理组中,750 mg·L^(-1)处理的发芽率和发芽势分别为83.82%和59.56%(p<0.05),为组内最高;在植物激素处理组中,100 mg·L^(-1)GA_(3)溶液处理发芽率最高,达到81.19%(p<0.05);在强氧化剂处理组中,500 mg·L^(-1)KMnO4溶液处理的发芽率和发芽势分别为84.92%和46.03%(p<0.05),为组内最高.在这三种外源添加处理条件下,750 mg·L^(-1)KNO_(3)溶液处理的幼苗下胚轴长1.08cm,根长2.09 cm;100 mg·L^(-1)GA_(3)溶液处理的幼苗下胚轴长2.41 cm,根长2.01 cm;500 mg·L^(-1)KMnO4溶液处理的幼苗下胚轴长度1.21 cm,根长1.63 cm.综合比较发现,100 mg·L^(-1)GA_(3)溶液处理条件下明日叶种子发芽率高,且植株幼苗的根长及下胚轴长度也最好.本研究结果可为明日叶种植及同类种子繁育提供借鉴.

强封堵防塌型水基钻井液体系室内制备及其应用

选取目标区块进行了储层水化行为特性分析,提出了一种强封堵防塌型高性能水基钻井液体系。优选了封堵剂、降滤失剂、抑制剂与润滑剂为关键处理剂,对其流变性、封堵性、抑制性、润滑性、抗温性以及井壁稳定性进行了实验评价,并进行了现场应用测试。结果显示:基浆、3.0%磺化沥青及5%碳酸钙三者组合可实现体系滤失量最低,3%SAP+6%PAH+0.5%HB降滤失效果最佳,6%PEG和5%FH6为抑制剂与润滑剂。配制的水基钻井液体系滤失量几乎为0,页岩滚动回收率为96.99%,可以很好地起到井壁防塌稳定的效用,综合性能与油基钻井液体系相差不大。现场应用测试过程中高温高压失水量低至3.9 mL,钻井固相质量分数仅为5.29%,极压润滑系数显著低于非测试井,验证了该水基钻井液体系的实用性。

自张式膨胀管技术的研究与应用

孔内膨胀管钻探技术是保障复杂地层孔壁稳定的有效技术之一。本文针对易出现缩径、坍塌、掉块的强水敏性地层,提出了一种自张式膨胀管护壁方法,并根据该方法的护壁原理研制了相适配的新型扩孔钻具、膨胀管及膨胀管投送装置,在不改变钻孔结构的情况下,对复杂孔段进行局部扩孔,投送膨胀管借助自身张力自然弹开而固定在相应的扩孔段,实现钻进时护壁。通过室内及现场试验对机具进行了优化,最终取得了良好的应用效果。试验证明:该方法操作简单可靠、易于定位,相较于水泥浆护壁具有处理速度快、停待时间短、减少重复处理等优势,适用于岩心钻探领域多孔段复杂地层的固壁与护壁,有利于降低孔内事故处理的成本、提高钻进效率,具有较好的推广应用价值。

强富水区山岭隧道穿越断层破碎带施工技术研究

为降低隧道穿越断层破碎带施工中的涌水突泥风险,该文依托古兜山隧道实体工程,采用“TSP+地质雷达+超前地质钻孔”的地质超前预报技术,探明隧道掌子面前方的地层状况和富水程度,提出富水区隧道穿越断层破碎带施工关键技术。提出隧道洞口明挖法与隧道洞内光面爆破技术及洞内围岩段的双侧壁导坑法、单侧壁导坑法、三台阶七部法的开挖方式;采用S-Ⅴb型隧道衬砌结构型式与全断面帷幕注浆、加强泄水等技术相结合的支护方式,其中的整体承载结构为初期支撑系统和二次模筑衬砌的组合结构。该施工关键技术可有效避免古兜山隧道施工的突水涌泥现象,可指导类似工程的施工。

控水促根和稀播培育长叶龄壮根苗对烤烟干物质和氮磷钾积累的影响

本研究旨在探究控制水分、稀疏播种和微生物菌剂添加对烤烟干物质及养分积累的影响。以‘云烟87’为材料,设计控水促根和稀播培育长叶龄烟苗两个因素,分析了大田团棵期、打顶期、圆顶期的烤烟干物质积累与分配、氮磷钾养分积累与分配、氮磷钾肥料利用效率状况,采用η^(2)值大小评价了控水促根和稀播培育长叶龄烟苗及其互作的贡献率。结果表明:增加育苗盘孔径、添加微生物菌剂在基质中、水分管理为前漂后湿等措施培育大叶龄烟苗,可提高烤烟干物质积累量和干物质在烟叶分中分配比例,提高氮、磷、钾养分积累量,促进烤烟对吸收肥料中养分,提高烤烟干物质积累效率和烟叶生产效率。控水促根和稀播长叶龄及其互作对烤烟干物质积累的贡献率分别为30.42%、51.71%、17.87%,对烤烟氮积累的贡献率分别为24.44%、47.72%、27.84%,对烤烟磷积累的贡献率分别为25.69%、45.66%、28.65%,对烤烟钾积累的贡献率分别为30.00%、44.03%、25.97%。因此,在南方多雨稻作烟区,可采用控水促根培育措施来替代两段式育苗,培育适栽期长的壮苗,有利于促进烤烟早生快发,为优质丰产奠定基础。

水肥精量控制对西瓜嫁接苗生长的影响

为培育西瓜壮苗,减少水肥资源浪费,开展了在嫁接成活期控制不同基质含水量(95%~100%、70%~75%)和育苗期使用不同水溶肥包括磷酸二氢钾和氮磷钾平衡肥(15-15-15+TE)的水肥精量控制试验,比较分析了嫁接苗的成活情况、生长指标和壮苗指数。结果表明:冬春季在玻璃温室内培育西瓜嫁接苗,嫁接后7 d内以基质最大含水量保持在95%~100%,施用磷酸二氢钾肥水溶肥1000倍液4次(在砧木现1片真叶时、嫁接苗接穗现1片真叶时、接穗1叶1心时和接穗2叶1心时分别灌根1次)为宜,可提高嫁接成活率(95%),降低病苗率(5%),且壮苗指数(165.59)显著高于其他3个处理,有利于培育西瓜壮苗。

农田排水对地表水环境影响的调查

中国是农业大国,以保障食品供应安全为前提的农耕生产,还未将生态环境保护纳入生产过程进行管理。为进一步了解农耕生产对地表水环境的影响,支撑未来生态环境管理需求,选取具有代表性的独立水田和旱田作为实验区块,在备耕期追加底肥,泡田时段和农作物生长期施加农药、化肥、除草剂、杀虫剂等各个农事环节前后时段,跟踪监测实验区块内积水、外排水、周边受纳水体在实验区块排水前后的水质变化情况,共设置27个监测点位,收集4 184个实验数据。实验显示:农田排水会污染地表水环境,污染具有冲击性,且与农药和化肥的施用时间、种类和数量密切相关,并随农田农药和化肥肥效衰减而逐渐降低直至消失。

水氮运筹对强筋小麦干物质转运与籽粒产量的影响

为探讨冀东麦区水氮运筹对强筋小麦干物质转运与籽粒产量的影响,以强筋小麦品种津农7号为材料,采用裂区试验设计,以追氮春灌时间为主区[返青期追氮灌水(T_(1))、起身期追氮灌水(T_(2))和拔节期追氮灌水(T_(3))],氮肥运筹为副区[基施N 120 kg·hm^(-2)+追施N 120 kg·hm^(-2)(N1)、基施N 90 kg·hm^(-2)+追施N 120 kg·hm^(-2)(N_(2))和基施N 120 kg·hm^(-2)+追施N 90 kg·hm^(-2)(N_(3))],比较分析不同处理下津农7号籽粒产量、干物质转运和氮肥偏生产力的差异。结果表明,水氮运筹对津农7号的籽粒产量和穗粒数影响显著,不同处理下小麦籽粒产量为8734.82~9763.22 kg·hm^(-2),其中T_(2)N1和T_(2)N_(2)处理的籽粒产量显著高于其他处理;T_(2)的平均氮肥偏生产力较T_(1)和T_(3)分别高4.84%和1.88%,且T_(2)N_(2)处理最高。各处理花后干物质转运对籽粒产量的贡献率为57.35%~89.74%,说明小麦籽粒产量多源于花后干物质积累。T_(2)条件下成熟期小麦营养器官氮素积累量和籽粒氮素积累量均显著高于T_(1)和T_(3),且N_(3)下花前氮素转运效率较N_(2)无显著变化,说明追氮灌水前移至起身期可促进强筋小麦氮素转运及籽粒氮素积累。在本试验条件下,基施N 90 kg·hm^(-2),起身期灌水并追施N 120 kg·hm^(-2)可在协调小麦干物质和氮素的积累、转运和分配的同时稳定产量,提高氮肥利用率,从而实现强筋小麦节氮稳产。

关中地区持续性强对流天气成因分析及对农业的影响

为探讨关中地区罕见持续性强对流天气的成因和发生机理,客观分析此次过程对农业的影响情况。利用中国新一代全球大气/陆面再分析产品,常规高空、地面观测以及人工观测冰雹等资料,对2021年7月一次罕见持续性强天气的天气形势、水汽通量散度、假相当位温和环境参量以及影响农业生产的气象干旱指数、风雹对经济林果撞击深度等进行定量化客观分析。结果表明:此次关中地区持续性强对流天气受大气长波调整影响,前期以高空冷平流强迫类配置为主,后期属低层暖平流强迫类;低层偏东气流输送、副高外围西南暖湿气流、明显的水汽辐合和假相当位温密集区扩大造成显著的位势不稳定,是强对流天气发生的有利水汽和热力条件。较大对流有效位能、不稳定层结、垂直风切变增加和适当特殊层高度是强对流天气发生的有利潜势。强对流天气发生为旱情缓解和有效改善土壤墒情做出了积极贡献,但局地强降水和大风冰雹天气导致关中部分农作物倒伏,农田出现积水或土壤过湿现象,不利于玉米、猕猴桃等浅根系作物根部呼吸和养分输送,影响植株正常生长。关中地区多种经济林果出现0.07~0.32 cm的撞击深度,并出现脱落受损现象。研究结果为进一步加强农业气象服务和防灾减灾提供可靠依据。

强抑制超深水钻井液的制备与性能评价

针对超深水钻井中钻井液黏土水化抑制性和封堵性能不足、低温流变性差等问题,室内通过开环聚合、硅氢加成和季铵化3步反应,合成了一种以Si-O-Si为主链的聚硅氧烷抑制剂MNT。结果表明,MNT不影响强抑制超深水水基钻井液体系的流变性能;在20%岩屑污染下,黏度和切力增长幅度小;对比原有的强抑制超深水水基钻井液体系,加入MNT后体系二次滚动回收率从86.9%提升到93.6%,90℃下的防膨率从81.9%增强到91.5%,具有更好的抑制泥岩水化膨胀和水化分散的能力;同样压力下,NaCl比KCl更能抑制水合物生成。

基于强氢键作用的超分子微纳米涂层改性滤膜

为解决油水分离滤膜循环使用性差的问题,采用超分子鞣酸-聚乙烯醇(TA-PVA)黏结剂黏附鞣酸-铜(TA-CuⅡ)形成鞣酸-聚乙烯醇-铜(TA-PVA-CuⅡ)涂层改性聚偏氟乙烯(PVDF)膜,制备了具有稳定微纳米涂层的超亲水/水下超疏油膜(TA-PVA-CuⅡ@PVDF)。采用SEM、FTIR、XPS对制备的膜进行了表征,对改性前后PVDF膜的表面润湿性、油水分离性进行了测试,考察了二价铜离子改性时间对TA-PVA-CuⅡ@PVDF循环使用性以及涂层耐久性的影响。结果表明,在亲水性TA-PVA-CuⅡ微纳米涂层的作用下,TA-PVA-CuⅡ@PVDF的水接触角和水下油接触角分别可达到0°和151.0°,其对乳化油的分离膜通量和分离效率最高分别可达1169.30 L/(m^(2)·h)和99.99%,展现出优异的油水分离性能。二价铜离子改性时间为20 min时,TA-PVA-CuⅡ@PVDF循环稳定性和耐久性最佳,具有15次的循环分离次数,并且通量改变率为6.6%。