过热蒸汽对流加热油页岩原位开采基础实验研究

发布时间：2018-06-06 12:08

本文选题：油页岩 + 过热蒸汽　；参考：《太原理工大学》2015年硕士论文

【摘要】：近年来，随着世界石油能源的不断消耗和世界石油需求量的不断增加，常规石油资源正在逐渐减少。油页岩产物作为一种重要的石油补充和替代能源，已经受到了全世界的关注。开发油页岩不仅能够解决各国对石油的需求，而且能够降低对外石油的依存度，具有重大的战略意义。本文以过热蒸汽对流加热油页岩原位开采为背景，运用实验方法，对油页岩的热解性质、过热蒸汽作用下的产油/产气规律、过热蒸汽和模拟地应力共同作用下的油页岩破裂和热解规律做了研究，主要研究内容和结果如下：（1）利用热重分析仪对产自新疆的油页岩原样和过热蒸汽热解后的油页岩样粉样做热重分析，根据得到的失重曲线得出以下结论：新疆油页岩的热解过程分为三个阶段，第一阶段是水分的蒸发，持续时间较长，而且失重率低；第二阶段为油母质的热解，持续时间较短，油母质热解剧烈，失重率为7%～11%；第三阶段是无机矿物质的热解。过热蒸汽热解后的油页岩的失重率较低，与低温干馏技术相比，过热蒸汽更能充分的热解油页岩。热解温度高低和油页岩在该温度热解时所持续时间都会对油页岩的失重率产生较大的影响，热解温度越高失重率越大，，热解持续时间越长失重率越大。（2）利用自主研制的对流加热原位开采模拟实验台对新疆油页岩进行热解模拟实验，并对热解后生产的热解气体和页岩油做了实验分析，并分析了该实验结果产生的原因。研究表明，过热蒸汽热解油页岩产生的气体产物主要以有机气体产物、氢气、一氧化碳为主，并且在不同的时间段，各气体组分有所不同；相比于低温干馏技术，使用过热蒸汽热解得到的页岩油中，饱和烃和正构烃所占的比例更高，轻质烃和和中质烃所占的比例更高，页岩油品质更好。（3）利用自主研制的对流加热原位开采模拟实验台和模拟地应力系统，模拟了原位地应力状态下注蒸汽开采油页岩过程：首先是试件在三轴应力状态下的压裂过程，随着过热蒸汽的持续注入，在温度和压力共同作用下，试件在垂直于最小主应力的方向上被压裂，呈现出多个水平破裂面；然后是试件中油页岩的热解过程，过热蒸汽沿着压裂裂隙热解油页岩，热解产生的油气会随着过热蒸汽的流动带出试件外，在流动过程中，会有少量的页岩油产物附着在油页岩和混凝土上。（4）基于CT分析系统，对原位应力状态下过热蒸汽热解后的油页岩做细观分析后发现，越靠近注热区域的油页岩热解越充分，距离蒸汽注热区域最近且热解后的油页岩中大多为硬质矿物，而且在矿物中夹杂着圆形和椭圆形孔洞；稍远一点的油页岩中大多为有机矿物质，但是在该区域的油页岩中有裂隙的存在，但还是以微裂纹为大多数；远离蒸汽注热区域的油页岩中也是以有机矿物为主，而且只有少量的裂隙作为过热蒸汽流通的通道。
[Abstract]:In recent years, along with the world petroleum energy consumption and the world petroleum demand increasing, the conventional petroleum resources are decreasing gradually. As an important oil supplement and alternative energy, oil shale products have attracted worldwide attention. It is of great strategic significance to develop oil shale not only to solve the oil demand of various countries, but also to reduce the dependence of foreign oil. Under the background of in-situ extraction of oil shale with superheated steam convection heating, the pyrolysis properties of oil shale and the oil / gas production law under the action of superheated steam are studied by using experimental method. The fracture and pyrolysis of oil shale under the combined action of superheated steam and simulated in-situ stress are studied. The main contents and results are as follows: 1) the thermogravimetric analysis was used to analyze the crude oil shale samples from Xinjiang and the oil shale powder samples after superheated steam pyrolysis. According to the obtained weight loss curves, the following conclusions are drawn: the pyrolysis process of Xinjiang oil shale is divided into three stages. The first stage is the evaporation of water, the duration is longer, and the weight loss rate is low, the second stage is the pyrolysis of the oil matrix, the duration is shorter, the pyrolysis of the oil matrix is violent, the weight loss rate is 7% and the third stage is the pyrolysis of inorganic minerals. The weight loss rate of oil shale after pyrolysis with superheated steam is lower than that of low temperature retorting technology, and superheated steam can fully pyrolyse oil shale. Both the pyrolysis temperature and the duration of oil shale pyrolysis at this temperature will have a great effect on the weight loss rate of oil shale. The higher the pyrolysis temperature, the greater the weight loss rate of oil shale. The longer the pyrolysis duration is, the greater the weight loss rate of oil shale is. 2) the pyrolysis simulation experiment of Xinjiang oil shale was carried out by using the self-developed in situ convection heating test rig. The pyrolytic gas and shale oil produced after pyrolysis were analyzed experimentally, and the reasons for the result were analyzed. The results show that the gas products produced by superheated steam pyrolysis oil shale are mainly organic gas products, hydrogen gas, carbon monoxide, and the composition of each gas is different at different time periods. The proportion of saturated hydrocarbon and normal hydrocarbon is higher, the proportion of light hydrocarbon and medium hydrocarbon is higher, and the quality of shale oil is better. In this paper, the in-situ oil-shale production process with steam injection under in-situ stress state is simulated by using the self-developed convection heating in-situ mining simulator and the simulated in-situ stress system. Firstly, the fracturing process of the specimen under triaxial stress state is simulated. With the continuous injection of superheated steam, under the combined action of temperature and pressure, the specimen is fractured in the direction perpendicular to the minimum principal stress, showing multiple horizontal fracture surfaces, and then the pyrolysis process of the oil shale in the specimen. Superheated steam pyrolysis oil shale along fracturing fracture, the oil and gas produced by pyrolysis will flow out of the specimen with the flow of superheated steam. During the flow process, a small amount of shale oil products will adhere to oil shale and concrete. (4) based on the CT analysis system, the oil shale pyrolysis under in-situ stress is analyzed. The results show that the oil shale pyrolysis near the heat injection region is more adequate. Most of the oil shale closest to the steam injection zone and pyrolyzed are hard minerals, with circular and elliptical pores in the mineral, and the oil shale, a little farther away, is mostly organic, However, there are fissures in the oil shale in this area, but most of them are microcracks, and organic minerals are also dominant in the oil shale far from the region of steam heat injection, and only a small number of cracks are used as the passage of superheated steam flow.
【学位授予单位】：太原理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TD83

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