CO_2驱提高采收率技术效果的影响因素研究

CO_2驱油技术是国外一项成熟的提高采收率方法,受到世界各国油田的广泛关注。非均质性作为CO_2驱重要的油藏和操作参数,对CO_2驱提高原油采收率的影响很大。安默德(Ahmed)等人通过敏感性分析研究了主要参数对CO_2驱采收率和产量的影响。研究结果显示,在不同非均质性条件下,在合理的注入速率下,采用五点法井网,单井控制面积0.48km~2,短周期WAG,水平井段尽量位于产层下部,长度与井距相等,可获得最大采收率。美国朗之利韦伯油田是世界第三大CO_2驱油田,从1986年开始实施至今仍然在产,后期CO_2气窜严重,通过非均质性研究,调整各项参数,并尝试泡沫和凝胶调剖等技术,取得较好开发效果。国外在CO_2驱油技术的研究方法和手段上取得较大进展,对我国一些油田开展的CO_2驱油技术研究具有重要的指导和借鉴意义。     

喇嘛甸油田三元复合驱油井结垢机理分析及防垢措施探讨

三元复合驱注入体系由聚合物、碱、表面活性剂组成,通过三种驱替剂的协同效应,提高了驱油效率,是油田高含水后期进一步提高采收率的重要措施,在三元驱油体系注入地层的过程中,碱性的化学剂注入地层后,受地层温度、压力、离子组成和注入体系的pH值等因素的影响,油井出现严重的结垢现象,影响机采井正常生产,本文通过对三元复合驱腐蚀结垢机理的分析,对三元复合驱防腐防垢措施进行了探讨。     

CO_2驱窜逸影响因素研究

气窜已成为制约CO_2驱进一步扩大波及范围、提高采收率的重要因素。采用理论计算、室内实验和数值模拟方法,系统研究了中原油田濮城沙一下油藏CO_2驱窜逸机理,包括CO_2窜逸影响因素、CO_2与油水的扩散传质作用及溶解规律。利用长岩心驱替实验,分析了驱替压差、油藏非均质性、温度和开发方式对CO_2窜逸的影响规律。CO_2窜逸速度主要受驱替压差、温度、压力、以及油藏非均质性、注入方式等因素的影响,研究这些因素对窜逸速度的影响程度,可以为科学的封窜提供依据。     

基于储层非均质性评价二氧化碳驱油效果

随着中国各大油田开采力度的加大,开采阶段基本都进入了含水率较高的后期阶段,为了进一步满足日益增长的能源消费需求、提高采收率,CO_2驱油技术逐渐走入人们的视野,备受各大油田的青睐,成为目前油田上提高采收率的重要技术之一。CO_2驱油效果受众多因素影响,油藏非均质性是其中一个非常重要的因素。本文基于油藏非均质性对CO_2驱油效果的影响程度做出评价,并在评价结果的基础上进一步完善非均质油藏CO_2驱油方法。重点分析了两种非均质性对CO_2驱油效果的影响,评价了两种非均质性对CO_2驱油效果的影响程度。     

混相溶剂法降低CO_2驱最小混相压力研究

CO_2驱是目前国内外提高原油采收率和实现温室气体埋存的一项重要技术,开展CO_2混相驱方面的研究具有十分重要的意义。但在低渗透油藏中,受到最小混相压力值的限制,CO_2驱较难实现混相驱。本文提出了一种通过混相溶剂法实现降低CO_2最小混相压力的方法,通过细管实验法,研究了其降低最小混相压力的效果;通过室内驱油实验,研究了其提高CO_2驱油采收率的效果。实验结果表明,注入段塞尺寸为0.3%HCPV的柠檬酸异丁酯后,测得的最小混相压力值降低了2.3 MPa;当注入段塞尺寸为0.3%HCPV时,混相驱阶段采收率最大,为17.22%,较单纯注入CO_2驱油方案提高了7.97个百分点。以上实验结果均表明,利用该混相溶剂法降低CO_2驱最小混相压力具有一定可行性。     

层内自生二氧化碳驱油技术在大情字井油田应用研究

大情字井油田属于低渗、特低渗透油藏,成藏条件复杂。由于沉积特征及天然裂缝发育,导致该油田存在明显的水驱优势方向;又由于水井井况问题严重,局部井网不完善,地层能量不足,导致油田的开发效果及原油采收率受到了影响,因此提出层内自生二氧化碳吞吐采油工艺技术。该技术具备CO_2驱油技术的普遍优点,还能够解决常规CO_2技术存在的气源不足、污染严重、投资大、腐蚀等问题。针对地层能量不足井、近井地带结垢严重井、水淹水洗严重井等不同类型油井开展了层内注入自生CO_2体系试验。通过不同类型井的增油效果来明确大情字井油田自生CO_2的适应性,制定适应大情字井油田的层内生成CO_2吞吐井的筛选标准。本文针对大情字井油田的特点筛选了自生二氧化碳体系,并开展试验,增油效果明显,为大情字井油田增能措施提供新的方向。     

北东块二类油层三元复合驱采出离子变化与结垢状况分析

三元复合驱由于碱的加入,当碱性的化学剂注入地层后,受地层温度、压力、离子组成和注入体系的pH值等因素的影响,与地层岩石和地层水发生包括溶解、混合和离子交换在内的多种反应,进而生成沉淀,造成结垢,影响生产和提高采收率。目前北东块二类油层三元复合驱已有部分井开始结垢,本文总结了采出液中各项离子的来源及相互间可能进行的化学反应,并对目前试验区采出液中各项离子含量的变化情况进行分析,通过对结垢井的离子变化规律研究,判断试验区目前结垢状况,进而为下一步防垢、除垢工作做好准备。     

CO_2提高采收率技术在美国的应用研究

国外二氧化碳驱油技术始于20世纪50年代,目前已成为主要的提高采收率技术之一。美国是开展二氧化碳驱油项目最多的国家之一,CO_2驱开始于1972年,已在多个油田开展实际应用并取得显著成果,调研了美国应用CO_2提高采收率技术的大量成功案例,总结并展望了未来CO_2提高采收率技术在碳封存领域的应用前景。     

致密油藏CO_2驱工艺参数优化试验研究

针对姬源油田H3区块注水开发后期注水压力过高、地层亏空严重等问题,开展致密油藏CO_2驱试验研究。以实际地质资料和拟合良好的流体物性参数为依据,通过数值模拟技术,建立CO_2驱概念模型对注入方式、注入速度、气水比例、转注周期四个参数进行优化。研究结果表明,针对H3区块开展的CO_2驱工艺参数优化对驱油效果显著提高。     

小井距高浓度聚驱油井含水回升原因分析

室内研究表明,一类油层聚驱后高浓度聚驱仍能进一步提高采收率8个百分点左右。为进一步探索聚驱后提高采收率方法,在喇嘛甸油田北东块葡Ⅰ1-2油层开展了聚驱后缩小井距高浓度聚合物驱现场试验。试验注入高浓度聚合物0.095PV后油井开始见效,取得明显增油降水效果,但随着高浓度聚合物溶液的注入,目前试验区含水出现回升趋势。文章通过对注采井开发状况分析,结合油层剖面动用状况、射孔情况、连通和发育状况等地质因素研究,分析含水回升原因,对试验区下步综合调整有一定指导意义。     

Insect antifeedant properties of anthranoids from the genusVismia

Vismiones and ferruginins, representatives of a new class of lypophilic anthranoids from the genusVismia were found to inhibit feeding in larvae of species ofSpodoptera, Heliothis, and inLocusta migratoria.     

Direct observation of freeze-thaw instability of latex coatings via high pressure freezing and cryogenic SEM

Despite its industrial importance, the subject of freeze-thaw (F/T) stability of latex coatings has not been studied extensively. There is also a lack of fundamental understanding about the process and the mechanisms through which a coating becomes destabilized. High pressure (2100 bar) freezing fixes the state of water-suspended particles of polymer binder and inorganic pigments without the growth of ice crystals during freezing that produce artifacts in direct imaging scanning electron microscopy (SEM) of fracture surfaces of frozen coatings. We show that by incorporating copolymerizable functional monomers, it is possible to achieve F/T stability in polymer latexes and in low-VOC paints, as judged by the microstructures revealed by the cryogenic SEM technique. Particle coalescence as well as pigment segregation in F/T unstable systems are visualized. In order to achieve F/T stability in paints, latex particles must not flocculate and should provide protection to inorganic pigment and extender particles. Because of the unique capabilities of the cryogenic SEM, we are able to separate the effects of freezing and thawing, and study the influence of the rate of freezing and thawing on F/T stability. Destabilization can be caused by either freezing or thawing. A slow freezing process is more detrimental to F/T stability than a fast freezing process; the latter actually preserves suspension stability during freezing. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004 in Chicago, IL. Tied for first place in The John A. Gordon Best Paper Competition.     

Ethanol and (−)-α-Pinene: Attractant Kairomones for Bark and Ambrosia Beetles in the Southeastern US

In 2002–2004, we examined the flight responses of 49 species of native and exotic bark and ambrosia beetles (Coleoptera: Scolytidae and Platypodidae) to traps baited with ethanol and/or (−)-α-pinene in the southeastern US. Eight field trials were conducted in mature pine stands in Alabama, Florida, Georgia, North Carolina, and South Carolina. Funnel traps baited with ethanol lures (release rate, about 0.6 g/day at 25–28°C) were attractive to ten species of ambrosia beetles (Ambrosiodmus tachygraphus, Anisandrus sayi, Dryoxylon onoharaensum, Monarthrum mali, Xyleborinus saxesenii, Xyleborus affinis, Xyleborus ferrugineus, Xylosandrus compactus, Xylosandrus crassiusculus, and Xylosandrus germanus) and two species of bark beetles (Cryptocarenus heveae and Hypothenemus sp.). Traps baited with (−)-α-pinene lures (release rate, 2–6 g/day at 25–28°C) were attractive to five bark beetle species (Dendroctonus terebrans, Hylastes porculus, Hylastes salebrosus, Hylastes tenuis, and Ips grandicollis) and one platypodid ambrosia beetle species (Myoplatypus flavicornis). Ethanol enhanced responses of some species (Xyleborus pubescens, H. porculus, H. salebrosus, H. tenuis, and Pityophthorus cariniceps) to traps baited with (−)-α-pinene in some locations. (−)-α-Pinene interrupted the response of some ambrosia beetle species to traps baited with ethanol, but only the response of D. onoharaensum was interrupted consistently at most locations. Of 23 species of ambrosia beetles captured in our field trials, nine were exotic and accounted for 70–97% of total catches of ambrosia beetles. Our results provide support for the continued use of separate traps baited with ethanol alone and ethanol with (−)-α-pinene to detect and monitor common bark and ambrosia beetles from the southeastern region of the US.     

Methyl 2,4,6-decatrienoates Attract Stink Bugs and Tachinid Parasitoids

Halyomorpha halys (Stål) (Pentatomidae), called the brown marmorated stink bug (BMSB), is a newly invasive species in the eastern USA that is rapidly spreading from the original point of establishment in Allentown, PA. In its native range, the BMSB is reportedly attracted to methyl (E,E,Z)-2,4,6-decatrienoate, the male-produced pheromone of another pentatomid common in eastern Asia, Plautia stali Scott. In North America, Thyanta spp. are the only pentatomids known to produce methyl 2,4,6-decatrienoate [the (E,Z,Z)-isomer] as part of their pheromones. Methyl 2,4,6-decatrienoates were field-tested in Maryland to monitor the spread of the BMSB and to explore the possibility that Thyanta spp. are an alternate host for parasitic tachinid flies that use stink bug pheromones as host-finding kairomones. Here we report the first captures of adult and nymph BMSBs in traps baited with methyl (E,E,Z)-2,4,6-decatrienoate in central Maryland and present data verifying that the tachinid, Euclytia flava (Townsend), exploits methyl (E,Z,Z)-2,4,6-decatrienoate as a kairomone. We also report the unexpected finding that various isomers of methyl 2,4,6-decatrienoate attract Acrosternum hilare (Say), although this bug apparently does not produce methyl decatrienoates. Other stink bugs and tachinids native to North America were also attracted to methyl 2,4,6-decatrienoates. These data indicate there are Heteroptera in North America in addition to Thyanta spp. that probably use methyl 2,4,6-decatrienoates as pheromones. The evidence that some pentatomids exploit the pheromones of other true bugs as kairomones to find food or to congregate as a passive defense against tachinid parasitism is discussed.     

2007～2008年世界塑料工业进展

收集了2007年7月～2008年6月世界塑料工业的相关资料,介绍了2007～2008年国外塑料工业的发展情况,提供了世界塑料产量、消费量及全球各类树脂的需求量及产能情况.按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(尼龙、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、特种工程塑料(聚苯·硫醚、液晶聚合物、聚醚醚酮)、通用热固性树脂(酚醛、聚氨酯、不饱和聚酯树脂、环氧树脂)不同品种的顺序,对树脂的产量、消费量、供需状况及合成工艺、产品应用开发、树脂品种的延伸及应用的进一步扩展等技术作了详细介绍.     

2005～2006年国外塑料工业进展

收集了2005年7月～2006年6月国外塑料工业的相关资料,介绍了2005—2006年国外塑料工业的发展情况。提供了世界塑料产量、消费量及全球各类树脂生产量以及各国塑料制品的进出口情况。作为对比,介绍了中国塑料的生产情况。按通用热塑性树脂（聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂）、工程塑料（聚酰胺、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚）、通用热固性树脂（酚醛、聚氨酯、不饱和树脂、环氧树脂）、特种工程塑料（聚苯硫醚、液晶聚合物、聚醚醚酮）的品种顺序,对树脂的产量、消费量、供需状况及合成工艺、产品开发、树脂品种的延伸及应用的扩展作了详细的介绍。