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大庆长垣外围特低渗透扶杨油层CO_2非混相驱油试验研究 总被引:2,自引:0,他引:2
大庆长垣外围有3×108t特低渗透的扶杨油层储量在注水开发条件下难以有效动用,为提高这部分储量的有效动用率,开展了CO2非混相驱油试验研究。PVT测试结果表明,扶杨油层原油较稠,体积系数小,膨胀性和收缩性小,溶解系数较低;CO2驱油细管实验最小混相压力为29 MPa,比原始地层压力高8.6 MPa,现场试验为非混相驱;长岩心实验CO2驱油采收率比注水高4~6个百分点。综合室内可行性评价实验结果看,大庆长垣外围扶杨油层开展CO2驱油试验是可行的,并于2003年初在宋芳屯油田南部开辟了注气试验区,有注气井1口,采出井5口。矿场试验结果表明,CO2驱油能够使特低渗透、裂缝不发育的扶杨油层建立起有效驱动体系,从根本上改善其开发效果,该技术有望成为特低渗透扶杨油层有效动用的可行技术。 相似文献
23.
对河南省栾川县大练沟泥石流治理的经验总结 总被引:1,自引:0,他引:1
随着国民经济迅速发展,对矿产资源的需求日益增多,20世纪七、八十年代的开采只追求产量和经济效益,而忽视了对环境的保护,开采的矿渣乱排乱放现象非常严重,严重破坏了环境,象这样的矿山在全国各地有很多,随着时间的发展,松散堆积的矿渣在洪水的作用下顺着沟道倾泻而下,形成泥石流,对下游的人民生命财产造成严重的破坏和威胁,矿山泥石流逐步发展,进入发展期和活跃期,必将造成更大的危害。因此对这样的泥石流沟进行研究和治理是很有必要的。在对河南省栾川县大练沟泥石流的治理过程中,得出以下几点体会,现总结归纳出来,希望对类似泥石流沟的治理提供借鉴。 相似文献
24.
The 2004 Chuetsu earthquakes of Niigata (Japan) triggered numerous landslides, and the most widespread types of landslides
were highly disrupted, relatively shallow slides and soil (debris) flows. This paper presented a method to evaluate slope
instability using Newmark displacement on a pixel-by-pixel basis in a given area. The proposed method was able to integrate
Newmark displacement modeling and Monte Carlo simulations within geographical information systems. In the modeling, an empirical
attenuation relationship was utilized to calculate Arias intensity over this study area, and the variability of geotechnical
parameters was taken into account to calculate coseismic landslide displacement. Before deriving the displacement from related
inputs, the Monte Carlo simulations ran 1,500 times and generated 1,500 displacement values for each grid cell, and then means
and standard deviations of displacement were calculated and probabilistic distributions can be obtained. Finally, given 10 cm
as a threshold value of displacement, estimated probabilities of displacement exceeding 10 cm were shown as a map of seismic
landslide hazards. The resulting hazard map was classified into four categories from very low to high level. 相似文献
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The kinetics of the aqueous phase reactions of NO3 radicals with HCOOH/HCOO– and CH3COOH/CH3COO– have been investigated using a laser photolysis/long-path laser absorption technique. NO3 was produced via excimer laser photolysis of peroxodisulfate anions (S2O
8
2–
) at 351 nm followed by the reactions of sulfate radicals (SO
4
–
) with excess nitrate. The time-resolved detection of NO3 was achieved by long-path laser absorption at 632.8 nm. For the reactions of NO3 with formic acid (1) and formate (2) rate coefficients ofk
1=(3.3±1.0)×105 l mol–1 s–1 andk
2=(5.0±0.4)×107 l mol–1 s–1 were found atT=298 K andI=0.19 mol/l. The following Arrhenius expressions were derived:k
1(T)=(3.4±0.3)×1010 exp[–(3400±600)/T] l mol–1 s–1 andk
2(T)=(8.2±0.8)×1010 exp[–(2200±700)/T] l mol–1 s–1. The rate coefficients for the reactions of NO3 with acetic acid (3) and acetate (4) atT=298 K andI=0.19 mol/l were determined as:k
3=(1.3±0.3)×104 l mol–1 s–1 andk
4=(2.3±0.4)×106 l mol–1 s–1. The temperature dependences for these reactions are described by:k
3(T)=(4.9±0.5)×109 exp[–(3800±700)/T] l mol–1 s–1 andk
4(T)=(1.0±0.2)×1012 exp[–(3800±1200)/T] l mol–1 s–1. The differences in reactivity of the anions HCOO– and CH3COO– compared to their corresponding acids HCOOH and CH3COOH are explained by the higher reactivity of NO3 in charge transfer processes compared to H atom abstraction. From a comparison of NO3 reactions with various droplets constituents it is concluded that the reaction of NO3 with HCOO– may present a dominant loss reaction of NO3 in atmospheric droplets. 相似文献
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Discrete numerical modelling of rockfill dams 总被引:1,自引:0,他引:1
The aim of this study is to obtain quantitative information on the behaviour of rockfill used in embankment dams, and particularly on the influence of block breakage on the displacement field, from a numerical analysis using the Distinct element method. A methodology is set up to define the resistance of the 2D particles so that the same probability of breaking blocks may be reproduced as in a 3D material. The model uses the discrete element code PFC2D (Itasca Consulting Group Inc., PFC2D (Particle Flow Code in Two Dimensions), Version 3.0, 2002) and considers breakable clusters of 2D balls. The different parameters are determined from experimental data obtained from laboratory tests performed on rock blocks. The model is validated by comparing the results of the simulation of shearing tests with actual triaxial tests on rockfill material published in the literature. The numerical analysis of block crushing in an actual dam is proposed in the last part of this paper. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
30.