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111.
In the process of steam stimulation exploitation of viscous crude oil, the injected water, at high temperature and under high pressure, reacts intensively with the host rock. This kind of water–rock interaction in Liaohe Shuguang Oil Field was studied on the basis of analysis of water composition changes, laboratory experiments, mineral saturation indices analysis, and mass balance calculation. Compared with the injected water, the changes of the composition of discharged water are mainly the distinct decrease of pH, Na+, SiO2 and Cl−, as well as the increase of K+, Ca2+, Mg2+, SO
4
2−
and HCO
3
−
. Laboratory experiments under field conditions showed: the dissolution sequence of minerals quantitatively is quartz>potassium feldspar>albite, and the main change of clay minerals is the conversion of kaolinite to analcime. Mass balance calculation indicated during the process of steam stimulation, large quantities of analcime are precipitated with the dissolution of large amounts of quartz, kaolinite, potassium feldspar, and CO2. These results correlated very well with the experimental results. The calculated results of Liaohe Shuguang Oil Field showed that during the steam stimulation for viscous crude oil, the amounts of minerals dissolved (precipitated) are huge. To control the clogging of pore spaces of oil reservoirs, increased study of water–rock interaction is needed. 相似文献
112.
M. Hamami 《Geotechnical and Geological Engineering》2006,24(5):1271-1292
The work presented in this paper comes as part of a research program dealing with the thermomechanical behaviour of rock salt.
It aims to study laboratory and in-situ long-term behaviour by means of creep tests with deviator and temperature changes. The laboratory results, using a triaxial
multi-stages creep tests, highlighted the strain hardening character of rock salt. Furthermore, the in-situ results, using a borehole dilatometer multi-step creep test, have shown that the drilling is carried out in a weakly stressed
pillar. The interpretation of the laboratory results, using the J.LEMAITRE law, did not indicate full agreement with all the
test results. As a result a ‘double’ J.LEMAITRE model, which takes into account a double strain hardening variable, has been
put forward. The validation of this model on the laboratory creep tests is very satisfactory. Furthermore, the activation
energy seems satisfactory to represent the influence of the temperature. The in-situ behaviour modelling is clearly more complex than the modelization based on laboratory tests. In fact, it seems that if the
rock salt behaviour is maintained by J.LEMAITRE law, it is necessary to vary with the stress, at least, one of the parameters
assumed constant in the basic law. 相似文献
113.
Connectivity is an important measure for assessing flow transport in rock, especially through fractures. In this paper, rock
fracture systems are modelled by a discrete fracture model simulated by a marked point process. A connectivity index is then
introduced to quantify the connectivity between any two points in space. Monte Carlo simulation is used to evaluate the connectivity
index for stationary cases and relationships between the connectivity index and the parameters of the discrete fracture model
are analysed. The average number of intersections per fracture, Xf, and the fracture intensity, P12 (P32), are calculated and the relationships between these parameters and the connectivity index are investigated, concluding that
Xf is the more suitable parameter for the classification of rock mass flow properties. The relationships between the connectivity
index and the percolation state of the fractured medium are also discussed. An edge correction is briefly discussed and a
practical example is used to demonstrate the method of computing the connectivity index. 相似文献
114.
A local-scale model for temperature-dependence of water-retention curves may be applicable to large scales. Consideration of this temperature dependence is important for modeling unsaturated flow and transport in the subsurface in numerous cases. Although significant progress has been made in understanding and modeling this temperature effect, almost all the previous studies have been limited to small scales (on the order of several centimeters). Numerical experiments were used to investigate the possibility of extending a local-scale model for the temperature-dependence of water retention curves to large scales (on the order of meters). Temperature effects on large-scale hydraulic properties are of interest in many practical applications. Numerical experiment results indicate that the local-scale model can indeed be applicable to large-scale problems for special porous media with high air entry values. A typical porous medium of this kind is the porous tuff matrix in the unsaturated zone of Yucca Mountain, Nevada, the proposed geologic disposal site for national high-level nuclear wastes. Whether this finding can approximately hold for general cases needs to be investigated in future studies. 相似文献
115.
116.
117.
118.
杨庄截潜工程趾板段建基面以下为弱风化白云岩和含燧石条带白云岩,透水性较强,造成库水漏失严重.为解决建基面以下基岩渗漏问题,采用趾板段帷幕灌浆封堵基岩裂隙而形成防渗帷幕,以减少库水漏失.通过趾板段帷幕灌浆达到封堵基岩裂隙的目的,满足工程设计的防渗要求. 相似文献
119.
采矿引起的边坡倾倒滑移变形机理与变形安全性分析研究—以抚顺西露天矿边坡为例 总被引:1,自引:0,他引:1
在矿山开发、水电建设过程中倾倒变形问题日渐突出。倾倒变形边坡一般具有反倾边坡结构,变形的过程和机理比较复杂、涉及的变形岩体范围较大、危害严重。论文以抚顺西露天矿边坡为例,通过岩体位移监测资料的跟踪分析、底面摩擦模拟试验,以岩体力学、松散介质力学原理为理论基础,探讨了采矿影响下边坡倾倒滑移体的变形机理,分析认为采矿引起的倾倒滑移变形问题是在特定的地质构造和采矿工程条件下产生的,并提出了岩体变形安全性分析方法。通过工程实例,验证了方法的实用性,并针对实际问题提出了变形整治对策。 相似文献
120.
油页岩综合利用对周围环境的影响——以抚顺矿区为例 总被引:3,自引:0,他引:3
世界能源日益减少的局面为油页岩的开发应用带来广阔的前景,但油页岩工业所带来的环境影响亦不容忽视。以抚顺油页岩为例,从油页岩综合利用和油页岩工业对环境的影响等方面系统讨论了在我国发展油页岩工业时,如何本着节约能源、保护环境、实现可持续发展的观念,利用现有先进技术,科学发展油页岩工业,降低生产过程中的固、液、气污染物对环境的危害。 相似文献