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51.
用试井方法确定注水后地层渗透率的变化 总被引:1,自引:0,他引:1
大港油田已进入开发中后期,高含水油田占73%,开发初期的一些参数已不适合现在开发的需要。研究出一套用试井方法确定注水以后地层渗透率变化的方法,对大港油田的增储上产具有重要意义。 相似文献
52.
粘土矿物是低渗砂岩储层的主要胶结物,对储层物性及开发过程中储层物性变化趋势有着重要的影响和控制作用。另外,粘土矿物也蕴含着大量沉积环境介质的物理化学信息,认识其自然规律,可以有效地指导预测有利储层,认识和改造油层。以鄂尔多斯盆地砂岩储层中的粘土矿物为研究对象,探讨分析粘土矿物对低渗储层性质的影响,该研究对含油气盆地低渗储层有效开发具有一定的参考价值。 相似文献
53.
54.
土壤中的多环芳烃(PAHs)类有机污染物的生物有效性低,不易降解。本文综述了影响污染土壤中多环芳烃降解的环境因素和促进降解措施的研究进展。影响土壤中多环芳烃降解的因素,包括水分、养分、土壤物理条件等;促进土壤中多环芳烃降解的措施有:向污染土壤添加有机溶剂、利用冯顿反应、添加堆肥和有机物料等。从目前研究来看,应当通过促进多环芳烃从土壤上解吸和培育具有较高多环芳烃降解能力的微生物来促进多环芳烃污染土壤的修复。 相似文献
55.
本文主要从土壤 pH ,重碳酸盐 ,和氮素形态等几方面综述了各种土壤因子对土壤缺铁失绿的影响 ,并提出了进一步加强研究的方向 相似文献
56.
本文从TBM地区目的层的地质和地球物理特征分析出发,以三维地震资料为基础,综合利用人工和神经网络波形分类等定性储层预测方法和利用反演及敏感地震属性分析,对TBM地区低孔渗砂岩分布区开展了砂体展布特征分析和天然气高产区预测研究。根据研究结果部署了10口钻井,已完钻的4口井中有3口获得高产气流(其中DK27井日产天然气36.8×104m3)。值得指出的是,目前所用的预测方法还不能预测厚度小于6m的单砂层或砂层组构成的储层。 相似文献
57.
On irrigation schemes with rotational irrigation systems in semiarid tropics, the existing rules for water allocation are based on applying a fixed depth of water with every irrigation irrespective of the crops, their growth stages, and soils on which these crops are grown. However, when water resources are scarce, it is necessary to allocate water optimally to different crops grown in the irrigation scheme taking account of different soils in the command area. Allocating water optimally may lead to applying less water to crops than is needed to obtain the maximum yield. In this paper, a three stage approach is proposed for allocating water from a reservoir optimally based on a deficit irrigation approach, using a simulation-optimization model. The allocation results with a deficit irrigation approach are compared for a single crop (wheat) in an irrigation scheme in India, first with full irrigation (irrigation to fill the root zone to field capacity) and second with the existing rule. The full irrigation with a small irrigation interval was equivalent to adequate irrigation (no stress to the crop). It is found that practicing deficit irrigation enables the irrigated area and the total crop production in the irrigation scheme used for the case study to be increased by about 30–45% and 20–40%, respectively, over the existing rule and by 50 and 45%, respectively, over the adequate irrigation. Allocation of resources also varied with soil types. 相似文献
58.
特低渗透油藏驱替及开采特征的影响因素 总被引:9,自引:6,他引:3
王文环 《油气地质与采收率》2006,13(6):73-75
应用非达西渗流理论和非线性弹性渗流理论,分析了影响特低渗透油藏驱替及开采特征的主要因素。研究结果表明,启动压力梯度和毛细管压力是影响特低渗透油藏驱替特征的主要因素;而影响特低渗透油藏开采特征的主要因素是储层的弹塑性,即储层的压力敏感性。在特低渗透油藏的开发中应适当缩小注采井距提高驱替压力梯度,采取整体压裂措施减小启动压力梯度,通过气驱或活性水驱油减小毛细管压力,及时补充地层能量以减少压力敏感性对储层的伤害。 相似文献
59.
Y.M. Al-Wahaibi C.A. Grattoni A.H. Muggeridge 《Journal of Petroleum Science and Engineering》2006,53(3-4):239-253
The changes in gas and oil relative permeabilities as miscibility is approached are of particular importance in multi-contact miscible displacements. These changes are a function of the detailed phase behaviour of the fluids and their physical properties as well as the properties of the porous medium itself.In this work, we investigate the behaviour of two-phase drainage and imbibition relative permeability curves of four, different, equilibrated fluid pairs from a three component, two-phase system (cyclohexene, isopropyl alcohol and water) that exhibits a critical point at ambient conditions. The tie-lines of these fluid pairs are at varying distances from the system's critical point. Equilibrium phase compositions and interfacial tensions (IFT) were determined for each of the four fluid pairs. Dynamic displacements were then performed in a linear two dimensional, bead-pack. Unsteady state, drainage and imbibition relative permeabilities were determined for the various pre-equilibrated mixtures. The experimental results show a clear change in relative permeability as the fluid pairs approach the critical point. As the interfacial tension decreases the non-wetting phase relative permeability increases more rapidly than the wetting phase relative permeability and hysteresis becomes less important.Two correlations [Coats, K.H., 1980. An equation of state compositional model: SPE J, 20 (5): 363-376.; Whitson, C.H., and Fevang, Ø., 1997. Generalized pseudo pressure well treatment in reservoir simulation. In Proc., IBC Conference on Optimization of Gas Condensate Fields.], commonly used to model the changes in relative permeability with interfacial tension, and the development of miscibility, were compared with the experimental data. The Coats correlation, which uses a single adjustable parameter to model the changes in both relative permeabilities and residual oil saturation as a direct function of the IFT, yielded an unacceptable match to the experimentally determined fractional flow. However the Whitson–Fevang correlation, which relates the changes in relative permeability to the capillary number using two adjustable weighting functions, presents a satisfactory match. 相似文献
60.
N. K. Acharya P. K. Yadav S. Wate Y. K. Vijay F. Singh D. Kavasthi 《Bulletin of Materials Science》2004,27(5):417-420
Ion irradiation of Si8+ ion beam of 100 MeV was scattered by a gold foil on a Mylar membrane of 25 Μm thickness in the form of film roll (width,
12.5 cm and length, 400 cm) at the Nuclear Science Centre, New Delhi. The characterization of etched nuclear tracks was carried
out by gas permeation measurements. The samples cut from the film roll of required size for permeability measurements were
etched in a controlled manner in a constant temperature bath of 6N NaOH solution. The opening of the conical etched tracks
was characterized by hydrogen gas permeation. 相似文献