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1.
作为非常规石油资源的油砂受到愈来愈多的重视。本文评述了世界油砂资源开发现状和中国油砂资源的利用前景,总结了工业上成熟的油砂沥青热碱水萃取技术分离沥青的流程,论述了热碱水萃取过程中沥青与矿物、粘土和气泡之间相互作用及其对沥青分离效率的影响;全面总结了油砂沥青热碱水萃取过程中温度、pH值、多价阳离子和加工助剂等物理化学条件对沥青与矿物之间相互作用和沥青有效分离的影响。最后指出油砂沥青热碱水萃取分离的最优化实验技术研究是值得进一步深入研究的方向,原子力显微镜的运用和不同萃取技术的综合运用将在改善沥青的萃取分离效果上发挥作用。  相似文献   

2.
Kaolin ores in Huichang contains these minerals of quartz sand, kaolin, mica and feldspars. In order to recover these valuable resources, some experiments of screening, classification, magnetic separation, grinding and flotation are carried out on the basis of the kaolin ore properties. The test results indicate that quartz sand concentrate can be directly obtained when vibrating screen size used is 10 meshes. Materials that are smaller than the screen hole are injected to hydraulic cyclones which controlling classification size is 325 meshes; kaolin concentrate containing above 33.70% Al2O3 and 0.37% Fe2O3 can be well beneficiated from the overflow through magnetic separation with one stage rougher and cleaner to remove iron. On the other hand, the hydrocyclone spigot flow to grinding and flotation with one stage rougher and two scavengers, mica and feldspars concentrate can be beneficiated in sequence. Therefore, these valuable minerals of kaolin ores can be realized comprehensive utilization.  相似文献   

3.
Both froth flotation and centrifugal concentration were used to pre-concentrate the oil sands froth treatment tailings prior to the recovery of heavy minerals (titanium and zirconium minerals). Over 90% of the heavy minerals were recovered into a bulk flotation concentrate that was about 50% of the feed mass at 85 °C without any reagents. The same recoveries were obtained at 50 °C with the addition of NaOH and/or sodium oleate. However, the flotation concentrate also recovered over 90% of the residual bitumen and much of the clays/slimes. Subsequent treatment of the flotation concentrate such as dewatering and bitumen removal would be difficult due to these residual bitumen and clays. On the other hand, a SB40 centrifugal concentrator recovered over 85% of the heavy minerals but less than 30% of the residual bitumen. With improved liberation the recovery of the residual bitumen into the concentrate could be further reduced. The particle sizes of the SB40 concentrates were also larger than the flotation concentrates, making subsequent processing much easier.  相似文献   

4.
As the most abundant copper containing resource and zinc containing resource, chalcopyrite and sphalerite/marmatite commonly coexist as Cu-Zn mixed ores in deposits. However, it is difficult to completely separate sphalerite and chalcopyrite by flotation, thus resulting in the existence of zinc impurity in copper concentrate. Sphalerite/marmatite existed in copper sulfide concentrate as impurity may lead to severe damage of the smelting equipment, and cause the waste of copper and Zn resources, it will also decrease of the sale price of copper concentrates. Therefore, the deep separation of zinc from zinc bearing copper sulfide concentrate is of great significance. In this work, selective chemical leaching was developed to efficiently remove zinc from zinc containing copper sulfide concentrate. Under the optimal condition (i.e., sulfuric acid concentration exceed 100 g/L, temperature of 80 °C, pulp density of 10%, leaching time of 48 h), over 85% Zn was extracted into the leaching solution together with only about 10% Cu and Fe, according to the leaching experiment. Leaching slurry had good solid-liquid separation characteristics, and zinc can be further effectively recovered from the leaching solution. According to X-ray diffraction (XRD) and scanning electron microscope/energy dispersive spectrometer (SEM/EDS) analysis, chalcopyrite was the main mineralogical phase in the residues, which can be regarded as high quality copper concentrate for metallurgy. Accordingly, a new process for deep and efficient separation of Cu-Zn mixed ores has been proposed.  相似文献   

5.
储层非均质性极大地影响储层内流体的流动和分布,在油气运移成藏和提高采收率研究中广受关注。储层内发生的差异化成岩作用是层内非均质性的重要成因,与烃类充注事件的相互关系也是致密砂岩油气成藏机理研究的核心内容。本文以鄂尔多斯盆地中西部上三叠统延长组长9储层为例,研究储层内砂岩所表现出的差异化成岩作用及其影响下的流体活动过程。系统的显微观察发现,长9储层主要由机械压实致密型砂岩、钙质胶结致密型砂岩、含水砂岩和含油砂岩等四类岩石组成。利用显微岩相学、紫外荧光光谱、包裹体均一温度测试、盆地模拟等技术综合分析表明,机械压实致密型砂岩在早成岩期即在压实作用影响下强烈塑性变形致密化;钙质胶结致密型砂岩在早成岩期就发生强烈的碳酸盐胶结作用而致密化。这两类砂岩在成岩中后期基本不能为流体活动提供孔隙空间。含水砂岩和含油砂岩均经历了复杂的差异化成岩过程,含油砂岩内可以辨识出至少三期沥青,含水砂岩则未见沥青残留。以含油砂岩中沥青质所对应的烃类充注为标志,重建了长9储层的成岩序列,划分出三期流体流动过程,烃类充注与成岩作用交替进行。含水砂岩大致可划分出相似的成岩过程,但未发生烃类充注。  相似文献   

6.
接触角对非饱和土中基质吸力的影响   总被引:5,自引:0,他引:5  
接触角是研究三相界面的一个基本物理量。非饱和土是典型的三相体,然而在非饱和土力学中对接触角的研究还比较少,目前还停留在假设阶段,通常假设接触角为某一固定值,甚至忽略接触角的影响。实际上接触角是随外界环境的改变而变化的。通过化学方法对砂土表面改性,从而提高砂土的接触角,使砂土由亲水性变为斥水性。在亲水性砂土中加入斥水性砂土以提高砂土的表观接触角,以此为基础制备不同接触角的试样进行吸力测量试验。试验结果表明,接触角对非饱和土中的基质吸力有重要影响,含水率相同时,随着接触角的增大基质吸力是不断减小的,当含水率增大到一定值时,基质吸力不受土体(亲水状态下)接触角的影响。当接触角增大到一定值时,非饱和土体中的基质吸力消失,即非饱和土体中不再存在负的孔隙水压力。  相似文献   

7.

Surficial deposits of the tidally influenced Australian shelf seas exhibit a variation in fades related to energy gradient. These deposits comprise a high energy gravelly facies, a mobile sand sheet facies and a low energy muddy sand facies. Such a facies distribution conforms generally with the existing model of continental shelf tidal sedimentation, derived for the west European tidal seas. However, the carbonate rich and mainly warm water deposits of the Australian shelf differ from the mainly quartzose and temperate cold‐water deposits of the European type case in terms of: (i) the role of seagrasses in trapping fine‐grained sediment; and (ii) the relative importance of the production of carbonate mud by mechanical erosion of carbonate grains. Seagrasses in Spencer Gulf, Gulf of St Vincent and Torres Strait are located in regions of strong tidal currents, associated with bedforms and gravel lag deposits. Thus, in the case of tropical carbonate shelves, seagrass deposits containing fine‐grained and poorly sorted sediments are located in close proximity to high energy gravel and mobile sand facies. In contrast, the European model (for temperate, siliciclastic shelves) places facies in a regional gradient with a wide separation (in the order of 50–100 km).

Of the locations reviewed, the Gulf of St Vincent, Bass Strait, southern Great Barrier Reef, Torres Strait and Gulf of Carpentaria exhibit zones of carbonate mud accumulation. The production and winnowing of carbonate mud from the mobile sand facies is a factor that must be taken into account in the assessment of a sediment budget for this facies, and which is of relatively greater importance for carbonate shelves. Insufficient data are presently available from the macrotidal North West Shelf to test the applicability of the model to this region.  相似文献   

8.
S.A. Ola 《Engineering Geology》1991,30(3-4):325-336
A brief review of the geology of the tar sand areas of Nigeria is given. Analysis shows that the tar sand used for the tests consists of a well graded silty sand (cmf) with about 5% clay; and 3–5% bitumen. Results presented show a very high in situ compressive strength of about 450 kN/m2, a high ratio of tensile to compressive strength of about 22%, peak shear strength parameters of Cp′=15kN/m2and φp′ = 19° and residual parameters of Cr =0, φr = 18°. The compacted tar sand behaved like an overconsolidated soil with a preconsolidating pressure, Pc of 140 kN/m2. In general, the results of the in situ strength tests indicate that the Nigerian tar sand behaved as a soft sandstone.  相似文献   

9.
内蒙×××蓝晶石矿可选性试验研究   总被引:2,自引:0,他引:2  
对内蒙×××蓝晶石矿采用脱泥-碱性介质浮选-磁选和脱泥-磁选-酸性介质浮选两种工艺流程进行可选性试验研究。结果表明,酸性介质浮选的分选效率和选择性较好。该矿采用脱泥-磁选-酸性介质浮选工艺流程,获得了较好的试验指标。  相似文献   

10.
我国北方内生磷矿主要集中在河北、辽宁、内蒙古,主要为赋存于绿岩带内的低品位晶质铁磷矿床,磁铁矿(含钛磁铁矿)-磷灰岩型矿石。矿石含磷低,易选,但选矿比大、成本高。利用研制出的适合北方低品位磷矿选矿的新型、高效的AW系列浮选捕收剂,解决了使用传统的脂肪酸类矿浆需要加温到35℃以上、需要加碱的问题。取得的科研成果已经应用于选矿实践,实现了工业化。  相似文献   

11.
Potato starch and dextrins resulting from thermolysis of potato starch in the absence of reagents and presence of -amino acids are promising depressants for separation of lead and copper minerals present in the Polish industrial copper concentrates. The polysaccharides were used for differential xanthate flotation of the final industrial concentrates produced by flotation with sulfhydryl collectors in the absence of depressants. The polysaccharides depressed galena and provided froth concentrate rich in chalcocite and other copper minerals as well as cell product containing lead minerals. The best results of separation were obtained in the presence of plain dextrin prepared by a thermal degradation of potato starch. The industrial concentrate containing 18.5% Cu and 5.5% Pb was divided into a froth product containing 38.1% Cu with 77% recovery of copper and a cell product assaying 7.3% Pb with 83% recovery of lead. It was accomplished using 2500 g/t of dextrin, 50g/t of potassium ethyl xanthate, and 50 g/t of frother (α-terpineol). The pH of flotation was 8.0–8.2.  相似文献   

12.
In situ recovery operations in oil sand deposits effectively represent man-imposed low to intermediate temperature metamorphism of the sediments in the deposit. In order to evaluate some of the reactions which occur, a factorial experiment was earned out in which a shale from the Lower Cretaceous McMurray Formation in the Athabasca oil sand deposit of Alberta, in the presence or absence of bitumen, was subjected to hydrothermal treatment with aqueous fluids of varying pH and salinity, at two different temperatures, for periods up to 92 hours. The aqueous fluid was analyzed and the analytical data subjected to statistical factor analysis and analysis of variance, which enabled identification of the main processes, namely, cation exchange, the production of two types of colloidal material, and the dissolution of quartz There is also saturation of the aqueous phase by. as yet unidentified, “total organic carbon” and complete conversion and removal of all nitrogen in the shale to the aqueous phase. These reactions have implications with regards to the economics of the in situ recovery process, specifically with respect to the reuse and/or disposal of the produced water and the plugging of the pore space and hence of reduction of permeability between the injection and production wells. As a result of these experiments it is suggested that monitoring of the composition of the produced water from in situ recovery operations in oil sand deposits would be advisable.  相似文献   

13.
In a hot, dry climate the presence of salt-loving vegetation (halophytes) may serve as a supplementary indicator of the presence of a salt-dome structure. Deep-seated oily water apparently forces the highly saline waters to the surface, where vegetation indicators may take two forms: where drainage is poor, the halophytes will be found along the anticline itself, but where drainage is good, the salt-loving plants concentrate along the perimeter of the salt-dome structure, sometimes virtually outlining it. In addition, the presence of gigantic and deformed plants in the area may indicate a high bitumen content. However, the influence of the deep oily water on the salinity of overlying deposits, soil and ground water varies with geologic conditions, depth and chemical composition of the ground water, conditions for its ascendance and conditions determining soil formation. The authors caution against over-simplification, since not every halophytic association indicates a buried salt dome; the specie composition of the association and presence or absence of bitumen-indicating forms must also be considered. --A. Eustus.  相似文献   

14.
Counter point bar deposits in the meandering Peace River, North‐central Alberta, Wood Buffalo National Park, are distinct from point bar deposits in terms of morphology, lithofacies and reservoir potential for fluids. Previously referred to as the distal‐most parts of point bars, point bar tails and concave bank‐bench deposits, counter point bar deposits have concave morphological scroll patterns rather than convex as with point bars. The Peace is a large river (bankfull discharge 11 700 m3 sec?1, width 375 to 700 m, depth 15 m, gradient 0·00004 or 4 cm km?1) in which counter point bar deposits are dominated by silt (80% to 90%), which contrasts with sand‐dominant (90% to 100%) point bar deposits. Beginning at the meander inflection (transition from convex to concave), counter point bar deposit stratigraphy thickens as a wedge‐like architecture in the distal direction until the deposit is nearly as thick as the point bar deposits. The low permeability silt‐dominant lithofacies in counter point bar deposits will limit reservoir extent and movement of fluids in both modern and ancient subsurface fluvial deposits. In the exploration and extraction of bitumen and heavy oil in subsurface fluvial rocks, identification and mapping of reservoir potential of point bar deposits and counter point bar deposits is now possible in the fluvial‐dominated tidal estuarine Lower Cretaceous Middle McMurray Formation, North‐east Alberta. Recent geophysical advances have facilitated imaging of some ancient buried point bar deposits and counter point bar deposits which, on the basis of morphological shape of sedimentary bodies observed from seismic amplitude, can be interpreted and mapped as depositional elements or blocks that contain associated sandstone or siltstone dominant lithofacies, respectively. As counter point bar deposits exhibit poor permeability and thus limit reservoir potential for water, natural gas, light crude, heavy oil and bitumen, counter point bar deposits should be avoided in resource developments. Geophysical imaging, interpretation and mapping of point bar deposit and counter point bar deposit elements provide new opportunities to improve recovery of bitumen and heavy oil and reduce development costs in subsurface cyclic steam stimulation and steam‐assisted gravity drainage projects by not drilling into counter point bar deposits.  相似文献   

15.
Particle hydrophobicity has been derived from Time of Flight Secondary Ion Mass Spectrometry (ToF-SIMS) measurements and its impact on the flotation behaviour of chalcopyrite investigated. Batch flotation tests were performed using a dithiophosphate-type of collector in different concentrations. Three flotation regimes were studied using particle size ranges of 20–38 μm, 75–105 μm and 150–210 μm. The individual particle contact angle, and hence, the distribution of contact angles of chalcopyrite within feed, concentrate and tail flotation samples has been determined using ToF-SIMS secondary ions. The effects of particle size and hydrophobicity on the flotation behaviour have been investigated using this new approach. The hydrodynamic effects of the particle size were highlighted by the different distributions of contact angles obtained for each concentrate size fraction, with fine and coarse sizes requiring higher average contact angles to float. This effect was overtaken by hydrophobicity when a high collector concentration was used. The broad distribution of contact angles observed in all samples, i.e. heterogeneity in hydrophobicity, has significant consequences for interpreting flotation behaviour. The methodology of analysis conducted in this study was applied to real ore and can be used as a quantitative, diagnostic tool for examining surface chemical factors affecting hydrophobicity. This new technique has promise and may advance the understanding of mechanisms, which may lead to better control strategies for improving flotation performance. Furthermore, any mineral–collector system can be targeted, provided appropriate calibration is performed.  相似文献   

16.
深水沉积层序特点及构成要素   总被引:6,自引:0,他引:6  
蒋恕  王华  Paul  Weimer 《地球科学》2008,33(6):825-833
本文在回顾当前国际上深水沉积研究热点的基础上,结合在墨西哥湾深水研究的成果系统描述了深水沉积的定义、形成机理、深水沉积层序及深水沉积构成要素的特点.深水沉积主要是在重力流作用下深水环境的沉积,主要形成于相对水平面下降和早期上升的时期,主要分布在低位体系域中.深水层序以凝缩段为边界,块状搬运沉积最早形成并直接位于层序界面上,其上被河道-天然堤沉积所覆盖.典型深水沉积的要素主要由河道、天然堤及越岸沉积、板状砂、块状搬运沉积等构成,这些沉积要素时空上有序地分布.深水河道是物源的主要通道和沉积的重要场所,从上游至下游河道弯曲度增加,能量逐渐减弱.侧向迁移明显,垂向上由富砂的顺直河道演化为相对富泥的弯曲河道.天然堤及越岸沉积以泥质为主,天然堤沿河道呈楔状分布,其近端砂岩含量高,地层厚且倾角较陡;远端砂岩含量低,地层薄且平缓,侧向连续性好但垂向连续性差.板状砂主要为深水扇前缘非限制性沉积,可分为块型和层型.块型侧向连续性好,同时垂向连通性高.层型侧向连续性好,垂向连通性差.块状搬运沉积主要是低水位期坡上沉积物失稳形成的各类滑塌体及碎屑流,其对下伏地层侵蚀明显,分布广泛,变形构造常见,可作为油气良好的封盖层.  相似文献   

17.
Ilmenite from Polish magnetite-ilmenite ores has been floated with tall oil. Chemical and mineralogical analysis of the flotation products established that the ores containing hercynite are difficult to upgrade. For ore A (18.7% hercynite and 32.8% ilmenite) and ore B (9% hercynite and 41.3% ilmenite) poor concentrates containing much less than the required 45% TiO2 have been obtained. It has been found that the higher concentration of hercynite in the feed, the lower the grade of concentrates in respect to TiO2 is obtained. Ilmenite ore containing a minor amount of hercynite (ore C, 0.15% hercynite and 12.3 ilmenite) gives a good concentrate. By means of microscopic observation it was established that hercynite floats together with ilmenite in the rougher flotation but is partially depressed in the cleaning and scavenging flotation.  相似文献   

18.
The use of discrete-element modelling (DEM) to simulate the behaviour of a highly idealized bituminous mixture under uniaxial and triaxial compressive creep tests is investigated in this paper. The idealized mixture comprises single-sized spherical particles (sand) mixed with bitumen and was chosen so that the packing characteristics are known and the behaviour of the mixture is dominated by the bitumen. The bitumen is represented as shear and normal (tensile and compressive) contact stiffnesses. Numerical sample preparation procedures for specimens containing spherical particles or clumps have been developed to ensure that the final specimen is isotropic and has the correct volumetric proportions. An elastic contact was used for the compressive normal contact stiffness and a viscoelastic contact was used for shear and tensile normal contact stiffness. Simulation results show that the idealized mixture is found to dilate when the ratio of compressive to tensile contact stiffness increases as a function of loading time. Uniaxial and triaxial viscoelastic simulations have been performed to investigate the effect of stress ratio on dilation and the numerical results have been verified with experimental data. The effects of introducing a proportion of frictional contacts and a more complex particle shape (clump) on dilation have been examined.  相似文献   

19.
国外浅变质碎屑岩型金矿床的含矿岩系以含碳和黄铁矿,夹火山物质和热水沉积物,金含量高为特征.在含矿岩系的沉积、成岩过程中,局部可以形成贫金的含矿层,少数情况下以至于形成金矿体.含矿岩系的变质作用可能形成金矿化,或为后来的成矿作用造成有利的物理和化学环境.岩浆作用为成矿作用提供了部分成矿物质,或为改造成矿作用提供热源和动力.金矿床受构造控制,位于地热正异常区,金矿床的形成与热水沉积成矿作用、变质成矿作用、岩浆期后热液成矿作用和大气降水改造成矿作用等有关.超大型浅变质碎屑岩金矿床的形成过程持续时间长,具有多期多阶段的特点.改造成矿作用在超大型浅变质细碎屑岩型金矿床形成中起重要作用,中生代形成的超大型金矿床中,构造岩浆活化作用叠加十分重要.  相似文献   

20.
郭帅  周训  吴旸  方斌  赵敬波  刘东林 《现代地质》2012,26(3):620-626
自然界中温泉形成的循环机制比较复杂,前人的实验模型研究很少有报导。根据断裂-深循环型温泉的特点可以设计一个简易实验装置,对温泉的形成进行模拟实验。实验采用充满砂的半圆弧形圆管实验装置,开展不同水温下热水循环的模拟实验,以便了解地下热水循环过程温泉流量的影响因素。利用室温实验计算出实验用砂的渗透系数K的范围在50.59~57.94 m/d。实验结果表明,温泉流量除与水头差、介质渗透系数和截面积呈正比例关系外,还随温度增大而增大。温泉形成过程是伴随能量转换的地下水循环过程,地下水从深部热源获得的热量使其温度升高,粘滞性降低,导致其流量增大。利用河北北部和广西东南部温泉的流量、温度数据进行验证,进一步分析了实验结果的合理性。  相似文献   

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