Geotechnical properties of combusted western oil shale

The engineering properties of solid waste produced by the combustion of Western oil shale are evaluated and discussed. Index properties and their variability, moisture—density relationships, shear strength, stress—strain characteristics, and hydraulic conductivity were evaluated in laboratory tests. Cementation caused by the formation of hydrous cements when combusted oil shale is exposed to water was found to be the most significant factor affecting its engineering properties. With increasing initial water content, shear strength increases and hydraulic conductivity decreases significantly, primarily because of cementation. Implications for the design of waste disposal embankments are discussed.     

Adsorption of copper and zinc by oil shale

 Oil shale is able to remove appreciable amounts of copper and zinc ions from aqueous solutions. It was noted that an increase in the adsorbent concentration with constant copper or zinc concentration resulted in greater metal removal from solution. An increase in the copper or zinc concentration with a constant sorbent concentration resulted in higher metal loading per unit weight of sorbent. For both metals, copper and zinc, equilibrium was attained after 24-h contact time. Increase in the initial pH or temperature of the metal solution resulted in an increase in the metal uptake per unit weight of the sorbent. Freundlich isotherm model was found to be applicable for the experimental data of Cu²⁺ and Zn²⁺. The results showed that oil shale could be used for the adsorption of the Cu²⁺ and Zn²⁺ with higher affinity toward Zn²⁺ ions. Addition of sodium salt to the metal solution influenced copper removal positively, but inhibited zinc removal. Received: 3 January 2000 · Accepted: 27 June 2000     

Adsorption of oxyanions by spent western oil shale: I. arsenate

The partitioning of arsenate between Paraho indirectly retorted and directly retorted oil shales and a combusted oil shale was examined with batch equilibrium adsorption isotherms. Arsenate adsorption was found to conform to the Freundlich adsorption model, and the combusted oil shale was found to have the greatest affinity for arsenate. The indirectly and directly retorted oil shale samples did not have statistically different affinities for arsenate. The greater adsorption capacity of combusted oil shale for arsenate was attributed to greater surface area and free iron oxide. Arsenate adsorption by combusted oil shale was not reversible. Upon dilution of the solution phase, arsenate did not desorb. Upon dilution of the retorted oil shale solutions, arsenate continued to be removed from solution. An evaluation of metal arsenate stability in the spent oil shale systems indicated that the retorted oil shale solutions were highly supersaturated with respect to magnesium and barium arsenates, whereas the combusted oil shale solutions were not supersaturated. The data were interpreted to indicate that adsorption reactions control arsenate solubility at short reaction times. As reaction times increase, precipitation reactions control soluble arsenate concentrations.     

Adsorption of oxyanions by spent western oil shale: II. selenite

The adsorption and desorption behavior of selenite by processed Green River Formation oil shales were examined. The selenite adsorption data could be quantitatively described by both the Freundlich and Langmuir isotherms. However, greaterR ² values were obtained for the Freundlich isotherms. Furthermore, selenite adsorption was not a function of the extraction process. The adsorption of selenite by the processed oil shales was irreversible. Upon dilution of the equilibrium systems, additional selenite removal from solution occurred. A thermochemical analysis of the adsorption and desorption equilibrium solutions indicated that the solutions were undersaturated with respect to a number of metal selenite solids. This indicates that precipitation processes are not influencing selenite behavior. However, not all selenite minerals were examined in the evaluation because of the lack of thermochemical data. An insufficient equilibration period for the adsorption study or the alteration of processed oil shale solids as a result of hydration reactions may also have hastened the additional removal of selenite during the desorption studies.     

Electron paramagnetic resonance studies of oil shale,shale oil,and spent shale

Electron paramagnetic resonance (EPR) reveals the presence of free radicals in raw shale, shale oil, and spent shale. Thirty-four samples of raw shale, and the spent shale and shale oil produced in the Fischer assay of these raw shale samples were studied. There is a significant correlation between the gallons per ton oil yield as estimated by Fischer assay and the spin density in the raw oil shale. However, the scatter in the data (due to uncertainties in sample preparation, Fischer assay results, and estimation of spins per gram of sample) limits the analytical utility of this finding. Sample preparation techniques affect the EPR signal.     

Response of oil shale to fragmentation by cylindrical charges

Summary This paper describes an experimental program that was conducted in 1981 through 1983 in the Anvil Points Oil Shale Mine near Rifle, Colorado. The objective was to examine the response of the kerogen rich oil shale to explosive charges in relatively large scale tests. Due to an alleged shortage of oil at that time the price per barrel of crude oil had reached nearly $40 and the United States was looking at oil shale as a possible source of hydrocarbon fuels.It was the intention of the fragmentation program to develop a modified in situ retort to recover the oil from the fragmented shale. Programs were already underway wherein the oil shale was being mined, transported to the surface, and retorted to remove the oil. This surface retorting resulted in a tremendous amount of spent shale (shale with the kerogen removed) which had to be handled and it was felt that this would lead to serious environmental problems. The scheme being investigated in the program at Anvil Points was one in which about 25% of the shale is mined, moved to the surface, and retorted. The remaining 75% of the shale was to be fragmented in place and an underground retort formed so that the oil could be removed without the necessity of transporting the shale to the surface.A successful method was not developed but the results of the program did provide information on the response of shale to both single hole and multiple hole explosive charges.     

Possibilities of oil shale mining under the Selisoo mire of the Estonia oil shale deposit

The paper presents results of the study on oil shale mining (Estonia underground mine) possibilities under the Selisoo mire. The Selisoo area is 2,051 ha in extent, and most of the mire is in natural state. Peat layer consists of thick (4.4–6.5 m) oligotrophic peat. Mining under Selisoo will go at depths 65–70 m under the surface. The mining field of the Estonia mine was planned between Ahtme and Viivikonna fault zones. The lowest hydraulic conductivity of carbonate rocks 0.11 l/day per m² is found in the Oandu layer and for peat it is 0.35–0.0002 m/day. Therefore, together they form a good aquitard. When the annual rainfall amount is the highest, the difference between horizontal water inflow and runoff is positive with 127,000 m³. Positive water balance is guaranteed in case of precipitation being at least 540 mm/year. The positive water balance is important for preserving the ecological system of Selisoo mire. For guaranteeing long-term stability of mine pillars, a new calculation method has been elaborated, based on the conventional calculation scheme, where the factor of safety is more than 2.3. Rheological processes are out of question, collapse of the pillars is impossible. Stability of the underground constructions and overburden rocks must be “eternal”. The criteria were elaborated for oil shale mining and will guarantee preservation of mires in natural or close to natural state.     

Characterization of Bulgarian oil shale kerogen revealed by oxidative degradation

A 13-step alkaline permanganate degradation of Bulgarian oil shale kerogen concentrate at ambient temperature was carried out. A high yield of oxidation products (90.1%) and a low yield of gaseous products (2.79%) were obtained. IR and ¹H NMR spectroscopic studies have shown that two significantly different types of high molecular products are present in kerogen. Further oxidation of these structures leads to the formation of low molecular aliphatic and aromatic acids, proven by gas chromotography (GC) and gas chromatography-mass spectrometry (GC-MS). The data obtained at these mild conditions allow us to acquire detailed information about the aromatic structures and polymethylene chain lengths in kerogen.The 5-step oxidation of the kerogen at 90 °C provides information about stable aromatic structures. Soluble and insoluble polyfunctional acids in acid medium have close molecular masses and spectral characteristics. The amount of benzene and naphthalene carboxylic acids is 11.3% of the organic matter of the oil shale.     

页岩油分类与评价

页岩油是以游离(含凝析态)、吸附及溶解(可溶解于天然气、干酪根和残余水等)态等多种方式赋存于有效生烃泥页岩地层层系中且具有勘探开发意义的非气态烃类。根据泥页岩地层中所含烃类相态、成因机理及勘探开发等特点,将页岩类油气划分为页岩气和页岩油等两类八种。结合页岩油特点,指出了我国页岩油形成条件和分布规律,即规模分布的有效生烃泥页岩、形成于深水-半深水相的富有机质泥页岩、较高的有机质丰度和适当的热演化程度以及较好的基质物性条件等是页岩油形成的主要条件。建立了中国陆相断陷湖盆页岩油发育模式,指出概率体积法可以作为页岩油资源评价的主要方法,提出了页岩油远景区、有利区及目标区优选的参数体系和标准。作为非常规油气能源的主要类型之一,页岩油将会对我国能源结构产生重要影响。     

Alkene transformations catalysed by mineral matter during oil shale pyrolysis

The effects of mineral matter on the pyrolysis behavior of an Australian aliphatic oil shale (Rundle, aromaticity = 0.21) have been studied. Besides confirming previous reports that mineral matter in highly aliphatic shales reduces the yield of oil from pyrolysis, the results clearly show that some mineral matter components such as montmorillonites and poorly ordered aluminosilicates can reduce the ratio of 1-alkenes to internal alkenes in oils. Isomerization is dependent on the type of aluminium coordination in the mineral matter and the tetrahedral aluminium is most efficient at altering alkene ratios. Although there is no evidence that mineral matter operates through a carbocationic mechanism to reduce the oil yield, the results strongly suggest that such a mechanism operates during alkene isomerization.     

The origin of nitriles in shale oil

Because nitriles are unlikely to occur naturally in a geological environment but have been reported as being present in some shale oils their origin was investigated. A careful infrared study could find no trace of the nitriles in the shale but it was shown, by infrared and gas chromatography with a nitrogen sensitive detector, that they do occur in some but not all oils. They are formed in the pyrolysis process by the reaction of car?ylic acids and ammonia liberated from minerals such as ammonium feldspars present in the shale. If both species are not present nitriles are not formed in the product oil. Pyrolysis of a brown coal, Loy Yang, in the presence of ammonia produced nitriles but none were generated when a more mature coal (Metropolitan) was similarly treated.     

油页岩的综合开发与利用

油页岩是一种重要的能源矿产，其资源量巨大，是石油和天然气的重要替代资源。本文简介了国内外油页岩开发利用的历史和现状，综述了油页岩综合开发利用的方式和途径。油页岩除用来炼油、燃烧发电外，其灰渣可用于材料制造、废气和污水处理。油页岩还在农业、制取氢气和有机酸以及提取金属元素等方面有广泛的用途。研究表明，油页岩综合开发利用能取得良好的资源、环境、经济及社会效益，对实现资源可持续发展具有重要作用。     

油页岩生产技术研究

总结了世界上从油页岩中制取页岩油的两大类生产技术方法:即地面干馏方法和地下转化方法,并总结了各方法的优缺点。根据我国油页岩资源的特点,认为应在发展和改进目前地面干馏技术的同时着力发展地下转化技术,为开采油页岩油进行技术改进。     

油页岩灰渣提取氧化铝制备铝酸盐发光材料

利用干馏后的油页岩灰渣,湿法提取氧化铝作为发光材料基质,经采用高温固相法合成 CaAl2O4 : Eu3 + ,R + ( R = Li,Na,K,Rb) 荧光粉。最佳合成条件为: 烧结温度1 200 ℃,烧结时间3 h,助熔剂加入量3 wt%,激活离子配比3 mol%; 实验发现辅助激活离子为Li + 时,CaAl2O4 : Eu3 + , Li + 的发光强度最强。样品荧光光谱分析结果表明,发射光谱在615 nm 处出现强谱峰,归属为Eu3 + 的5D0→7F2 跃迁辐射。     

Spent oil shale use in earthwork construction

Spent oil shale (or blaes) is a potentially valuable engineering material and is present in large quantities in the West Lothian area of Scotland. It can be used successfully as general fill or capping layer. However, due to its high quality it may be more suited to use as selected granular fill or sub-base. In particular, cement stabilisation will reduce frost susceptibility and may be a particularly appropriate outlet for spent oil shale for use as sub-base. However, an increase in control and testing may be required, having an effect on the cost of using such materials. Conditions under which spent oil shale should not be used are also identified.     

Elemental abundances in Green River oil shale

Spark-source mass spectrometric analysis of pyrolyzed Green River oil shale for trace element distribution showed enhanced concentrations for only lithium and beryllium. In general, trace elemental concentrations were found to be below anticipated crustal amounts. There appears to be no promise of any substantial accumulation of any trace elements within the organic matrix of Green River oil shale.     

全球页岩油形成分布潜力及中国陆相页岩油理论技术进展

全球非常规页岩层系油气资源丰富,富有机质页岩主要沉积在劳亚构造域和特提斯构造域的上侏罗统、渐新统—中新统、白垩系和上泥盆统4套页岩层系内。交汇分析北美典型页岩油区块产量与R_o数据关系,提出R_o为0.7%作为低熟页岩油和中高熟页岩油的界限,系统评价了全球116个盆地157套页岩层系中高熟页岩油、低熟页岩油技术可采资源量约2 512亿t,主要分布在北美洲、南美洲、北非和俄罗斯,以前陆盆地中新界、克拉通盆地古生界、裂谷盆地和被动大陆边缘盆地的中生界为主。海相页岩油受显生宙以来的海侵影响,富集在稳定克拉通和前陆等类型盆地中,具大面积稳定分布、成熟度适中等特征;陆相页岩油受暖室期气候影响,主要在坳陷、断陷等类型盆地中发育,以微纳米级无机孔隙和微页理裂缝为主要储渗空间通道,具有沉积相横向变化大、“甜点区段”局部富集等特征。中国石油工业正经历从“陆相页岩生油”向“陆相页岩产油”转变,初步形成源岩油气“进源找油”地质理论、陆相页岩油高效勘探及低成本开发技术体系,推动中国陆相页岩油取得重要突破。着力加强应用基础理论研究与关键技术攻关,构建地质-工程一体化模式,...     

鄂尔多斯盆地延长组页岩吸附热力学特征

为了研究陆相页岩的吸附机理,以鄂尔多斯盆地甘泉地区延长组页岩为研究对象,开展了不同温度下页岩等温吸附实验,分析了延长组页岩的吸附特性及等量吸附热特征,实现了页岩等温吸附量的预测。结果表明：超临界条件下,页岩等温吸附曲线极大值的出现与实验压力、比表面积及吸附气有关;与龙马溪组页岩相比,延长组页岩等量吸附热与吸附量呈正相关关系,符合幂函数拟合,且在相同吸附量下,延长组页岩等量吸附热较低,具有较强的非均质性和较弱的吸附作用力;等量吸附热不能反映吸附性能的强弱;基于等量吸附热的页岩等温吸附曲线预测方法在低实验温度、低气体压力条件下具有较高的预测精度。