南堡油田储层速敏性评价与影响因素

根据储层速敏性评价结果,南堡油田馆陶-东营组油藏为无-弱速敏,但在生产过程中,部分采油井出砂,注水井压力上升较快.通过对速敏评价数据分析,大部分岩心渗透率值呈上升趋势,没有下降的拐点,但存在明显上升的拐点;岩心速敏实验证明气测岩心正-反-正向渗透率值有不同程度的降低,单相油相渗透率正-反-正向渗透率值有所升高,进一步证明了储层存在速敏性;同时储层敏感性矿物分析进一步揭示了该储层的速敏损害程度.因此建议该储层在注采过程中,应控制合理的注采速度,降低速敏对储层造成的损害,提高储层采收率.     

应用核磁共振技术研究吐哈盆地低渗透储层渗流能力

应用核磁共振等实验技术对低渗透岩心的可动流体饱和度分布进行了定量测试,评价了储层流动能力,建立了可动流体饱和度与孔隙度、渗透率的回归关系,研究了影响储层渗流能力的因素;通过研究全直径岩心不同驱替阶段核磁共振弛豫时间谱的变化规律,探讨了低渗透储层渗流机理.研究表明:各类储层渗流能力差异较大,储层沉积微相、物性及微观孔隙结构决定了渗流能力的大小,注水驱替过程中剩余油主要分布在较小的毛管孔径中.该研究对制定油田调整措施具有指导意义.     

启动压力测定对吉林油田低渗透油藏开发效果的影响

存在启动压力梯度意味着流体的渗流偏离达西定律,为非线性渗流。通过对吉林油田部分区块的启动压力测定及测试结果分析,得出结论:在低速渗流条件下,流体的流动为非线性渗流;流体在低渗透岩心中渗流时,存在启动压力梯度;启动压力受样品渗透率的影响,相对气测渗透率来说,岩心的渗透率越低,水测和油测渗透率的下降越显著,其启动压力越高;驱替速度对低渗透油藏采收率有较大的影响,有一个最佳的驱替速度。     

气测速敏中气体滑脱效应的校正

气藏需用气体作为实验流体来测量储层的速敏性,按液测速敏的实验步骤和计算方法,则气测速敏指数和临界流量因受气体滑脱效应的影响而不准确.采用二次气测速敏实验步骤和新的计算方法可有效地校正气体滑脱效应影响,精确计算出气藏储层的速敏指数和临界流量.该方法运用于长庆上古致密砂岩气藏的速敏评价实验中,结果表明:速敏指数比常规实验方法要小,临界流量比常规实验方法大,储层的速敏损害程度由以前认为的中等水平变为弱水平,这与致密砂岩储层地质特征更相符合.     

苏里格气藏岩石应力敏感性研究

在气藏的生产过程中,随着流体的产出,净上覆岩层压力不断升高,储层孔隙结构因受到压缩而发生改变,导致渗流速度降低,使油气井的产能下降。在模拟地层温度及应力条件下,分析了苏里格气藏小岩心和全直径岩心渗透率与净上覆岩层压力之间的关系,研究了小岩心与全直径岩心的应力敏感性。结果表明:岩心渗透率均随上覆岩层压力的升高而逐渐降低,且随净上覆岩层压力的增大,渗透率下降的幅度逐渐变小,并表现出明显的渗透率滞后效应;苏里格气藏岩石的渗透率损害程度或应力敏感性属于中等;全直径岩心的应力敏感性较小岩心弱。     

疏松砂岩气藏渗透率敏感性实验研究

压敏、速敏、水敏的联合作用是疏松砂岩储层二次伤害的主要原因。利用松散岩心的套筒取心制样技术,对疏松砂岩油藏的露头岩心取样,通过疏松砂岩油藏应力敏感实验,模拟了不同驱替压差和驱动流速下储层的压敏、速敏、水敏变化,研究了疏松砂岩气藏特殊的渗透率敏感性机理。实验结果表明：疏松砂岩储层的渗透率越低,压敏越明显,压敏主要发生在应力变化的初始阶段,一般处在投产早期的近井地带,因此,多井低产、均衡开采将有利于稳产;疏松砂岩储层可动水会加剧压敏效应,因此随着压实和出水,中—低渗储层将转变为局部低渗—特低渗储层;疏松砂岩储层渗流过程中,微粒的运移同时具有疏通提渗和堵塞降渗的双重效应,在岩心尺度上,速敏体现在测试渗透率的异常升高,对于实际生产井,当气井产量发生显著变化时,可认为近井地层发生了微粒运移引起的速敏效应,即地层出砂。     

储气库井注气压力剧变诱发微粒运移实验模拟

微粒运移是一种重要的储层损害类型,地下储气库井在注气过程中因注气压力递增或波动而诱发储层微粒运移。当前,基于储气库注气压力变化下的微粒运移机理尚不明确,且少有系统开展模拟储气库注气压力变化下的微粒运移实验研究。为此,选用相国寺储气库黄龙组碳酸盐岩储层岩心制取裂缝岩心,分别开展了应力敏感实验、气体速敏实验、模拟储气库注气压力递增和压力波动情形下的岩心流动实验,测试压力递增和压力波动的岩心渗透率和出口端微粒浊度,并借助X射线衍射和扫描电镜等手段,分析储层微粒运移的潜在微粒类型,揭示了储气库注气压力动态变化诱发储层微粒运移机理。实验表明:①驱替压力递增和压力波动实验中的压力梯度远大于速敏实验中岩心发生速敏时(微粒运移)的临界压力梯度,岩心应力敏感程度为弱~中等偏弱;②驱替压力递增和波动下岩心平均渗透率损害率分别为77%和57%;③驱替压力递增和压力波动引起储层裂缝壁面脆弱结构附着能力下降是微粒运移的重要诱发机制。分析认为,注气压力递增或频繁波动会诱发储气库储层微粒运移损害,应预防钻完井过程中外来固相微粒侵入,并对储层中固有微粒进行清除。     

凝析气藏衰竭式开发影响因素实验

凝析气藏在衰竭式开采过程中,会有多种多样的因素制约着气藏的开发,研究其对采收率的作用结果对实际生产具有重要的意义。利用高温高压全直径岩心驱替装置,针对衰竭速度、束缚水饱和度、储层物性及流体性质这4种影响采收率的因素进行室内岩心衰竭实验研究,得到其对采收率的影响结果。实验结果表明,在这4种因素的影响下,凝析油的采收率会有不同程度的变化,而气的采收率波动范围不会太大。     

CO2驱油过程中孔喉结构对储层岩石物性变化的影响

注CO₂提高储层原油采收率过程中,储层中流体的渗流和分布受岩石孔喉结构控制,且注入的CO₂会引发原油中的沥青质沉淀,导致储层渗透率下降并改变储层的润湿性。通过在4块渗透率相似但孔喉结构不同的岩心上进行的混相和非混相的CO₂驱油实验研究了CO₂驱油过程中岩石孔喉结构对储层岩石物性变化的影响。基于岩石孔径分布和压汞曲线,根据分形理论对岩心孔喉结构特征进行定量评估。实验结果表明,在提高原油采收率方面,混相驱替比非混相驱替高12.2%~16.8%,孔喉结构相对均质的岩心比非均质岩心高18.1%~26.9%,在非混驱替时原油采收率受岩心孔隙结构的影响更明显。由于沥青质沉淀堵塞孔喉,混相和非混相驱替后岩心渗透率分别下降了7.5%~14.2%、4.0%~7.9%,且渗透率下降幅度与岩心孔喉结构分形维数呈正比。混相和非混相驱替后岩心的润湿指数分别下降了26.8%~59.8 ％、10.5%~21.6%。由于更大的CO₂波及体积,孔喉结构相对均质的岩心水湿性减弱更显著。混相驱替和均质的孔喉结构使岩心物性变化分布更均匀,且均质的孔喉结构可以在提高CO₂驱油效率的同时,减弱沥青质沉淀造成的岩心渗透率下降及润湿性变化,减弱程度分别为3.5%~6.7%、11.2%~33.0%。     

元坝气田不同类型储层气水两相渗流特征

气水两相相对渗透率曲线是描述产水气藏气水渗流规律的重要基础参数,但是采用水驱气方法还是气驱水方法来确定气驱水相对渗透率曲线仍存在较大争议。以元坝气田为研究对象,基于室内实验测试方法,系统开展了孔隙型、裂缝型岩心气驱水相对渗透率曲线测试,对比分析不同类型储层岩心气驱水相对渗透率曲线特征,推荐产水气藏气水相对渗透率曲线测试法。结果表明：裂缝型岩心气驱水相对渗透率曲线表现出凹形曲线特征,与常规的X形曲线特征差异较大;与裂缝型岩心比较,孔隙型岩心气驱水相对渗透率曲线整体右移,两相流动饱和度区间范围更宽、水相相对渗透率上升更慢。与气驱水方法相比,水驱气相对渗透率曲线的束缚水饱和度更接近储层实际情况、水相渗流能力弱、气相渗流能力大于水相,实验设计符合产水气藏气水渗流过程。因此,针对产水气藏的产能评价、开发方案编制等,建议采用水驱气法测试的气驱水相对渗透率曲线开展模拟计算。     

阿姆河右岸酸性气田井口冲蚀及对策

中亚土库曼斯坦阿姆河右岸气田群为高含H_2S和CO_2的碳酸盐岩气藏,单井产量高,井口设备均出现了不同程度的腐蚀。初步分析认为其原因是生产过程中仅考虑酸性介质对气井井口的化学腐蚀,而没有考虑气体流速对井口的冲蚀作用,极大地影响了气田的安全生产。为此,通过对节流阀上下游阀道、法兰面均出现明显坑状腐蚀的进一步分析,明确了化学腐蚀和气体冲蚀的交互作用是井口磨损的主要影响因素,气流冲刷腐蚀坑的化学腐蚀产物会加速冲蚀损害;进而借鉴冲蚀与腐蚀运行环境下的多相管流管道的磨损计算理论,计算了该运行环境下的冲蚀极限速度,得到了不同生产工况下节流阀的抗冲蚀流量;最后,根据气田生产情况,针对性地提出了按气井配产要求来选择采气树类型、节流阀通径及类型冲蚀的技术控制策略。此举为气田安全生产提供了工程技术保障。     

山前地区深井超深井套管防磨与减磨技术研究

针对山前地区深井超深井钻井过程中套管磨损严重的问题,在分析套管磨损机理的基础上,开展了山前地区套管防磨与减磨技术研究,基于技术研究成果及应用实践,得到如下结论:1应用Power V等垂直钻井系统控制井眼轨迹,特别是上部井段的狗腿度和井斜,可明显减小侧向力和磨损量,缩短套管磨损时间;2应综合考虑套管磨损率、磨损系数以及钻杆耐磨带本身的磨损量,优选出效果最优的耐磨带;在狗腿度严重的位置,可考虑采用一定数量的橡胶钻杆卡箍来减轻对套管的磨损;3山前地区钻井液采用CX-300减磨剂能够显著降低磨损速率,减轻套管磨损程度,但在不同钻井液体系使用之前应进行优化分析以确定最佳使用量;4在迪那204井使用高密度钻井液体系,全部采用优选的高密度重晶石粉代替铁矿粉作为加重剂,整个钻进过程中未出现钻具及套管磨损,迪那204井易损件消耗量仅为邻井迪那203井的左右,防磨减磨效果非常显著。     

Biodiesel Projects Helpful to Ease Energy Shortage

Nearly 7,000 hectares of biodiesel forest will take shape in the northern province of Hebei in 2008, part of a national campaign to fuel the fast growing economy in a green way. In no more than five years, the Pistacia chinensis Bunge, whose seeds have an oil content of up to 40 percent, will yield five tons of fruit and contribute about two tons of high-quality biological diesel oil, according to the provincial forestry administration.     

State Energy Base Proposed in Inner Mongolia

Experts recently suggested China set up a state energy base in lnner Mongolia Autonomous Region to ease its energy thirst. The survey was co-conducted by senior researchers from the National Development and Reform Commission, Development Research Center of the State Council, Chinese Academy of Sciences and the Ministry of Finance. To plan and establish strategic energy bases at state level is in line with the principle of ＂giving priority to energy saving and diversifying energy consumption with the utility of coal at the core.＂     

Influence of Shale Oil Boom in North America upon nternational Crude Price Flucturation

正Current stituation of shale oil development in the world The US The country is blessed with abundant shale oil resources and had matersed whole sets of theories and technologies needed for their exploration and development after years of practices.According to an assessment of shale oil resources in major countries and regions of the world issued by the U.S.Energy Information Agency(EIA),the US ranks the second in the world with its 6.8 billion tons of technically recoverable shale oil(shale oil in place is about 136.3 tons).About 8plays had been confirmed to have     

A Sintering-resistant Pd/C Composite Catalyst for Ethylbenzene DehydrogenationDeveloped by CAS Institute of Metals

Carbon deposition is a commonplace phenomenon occurringin the catalytic reaction process, in particular inthe system of direct dehydrogenation of ethylbenzene,because the reactant - ethylbenzene molecules on thesurface of metal oxide catalysts are prone to quickly formcarbon deposits, leading to deactivation of catalysts. Recently,the associate research fellow Mr. Liu Hongyangand the research fellow Mr. Su Dangsheng of the StateShenyang Material Science （United ） Laboratory of theInstitute of Metal Research, CAS by taking advantageof the carbon deposition process during direct dehydrogenationof ethylbenzene have ingeniously designeda Pd/C composite catalyst. This catalyst in comparisonwith the traditional commercial carbon nanotubesupported Pd catalyst shows a significantly improved performancein terms of its catalytic activity and sinteringresistantability.     

ZPEB Overseas Markets Keep Steady and Efficient Development

In recent years, Zhongyuan Petroleum Exploration Bureau （ZPEB） has made rapid development in overseas petroleum markets through its integrated reorganization. A new international business plattbrm established, aimed at becoming a highly ranked contractor with international petroleum engineering technology. ZPEB has expanded its business scope and scale, regulated the market structure,     

New Era for China-Brazil Relations

China and Brazil celebrated the 40th anniversary of establishing diplomatic relations between the two countries in July this year. Bilateral relations between China and Brazil have entered a new stage, and experts expect the already extensive cooperation between the two countries to deepen and broaden as Chinese President Xi Jinping made a state visit to Brazil in mid-July, which is his first state visit to Brazil since he assumed the office last year. The visit to China＇s largest trade partner in Latin America is at the invitation of Brazilian President Dilma Rousseff.     

Large Scale Ethylene Production Package Technology SuccessfullyDeveloped by CNPC

The CNPC Group has successfully developed a largescaleethylene production package technology with independentintellectual property rights, which has beensuccessfully applied in the 1.2 Mt/a ethylene revamp andexpansion project at the Daqing Petrochemical Complex（DPC）.     

Recent Advancements in Petroleum E & P Equipments in China

The role of equipments in oil and gas exploration and development had never been attached with so much importance as that in shale oil and gas boom in the U.S. With the help of massive hydraulic fracturing and horizontal drilling techniques, the U.S., the world＇s No. 1 oil importer even started to dream about energy self-sufficiency with its proudly high production of shale oil and gas from several major shale plays in the country. However, what behind this remarkable achievement are powerful multi-stage hydraulic fracturing machinery and smart tools for directional drilling.