油页岩高压击穿-等离子体加热转化机理研究

Oil shale，with the large of amount resources , could replace the conventional oil and gas resources and become the powerful guarantees for energy supply of our country. However, the technical difficulties of oil shale exploitation are extraordinary huge, and it still need to break through the bottleneck of the basic theory and key technologies for in-situ conversion of oil shale. The high voltage breakdown - plasma heating in-situ conversion technology is derived from the solid insulation high-voltage discharge mechanism. Its basic principle is: two high temperature resistant electrodes are set into the target layer of oil shale, and high voltage which would lead to the electro-discharge effect and a large number of plasma, and then the resistance between the electrodes reduces quickly; After that normal voltage, high frequency electricity is exerted between two electrodes which could make the plasma directional migration forming the current; then the oil shale resistance heating effect is used to heat the kerogen of oil shale to produce the shale oil and fuel gas. Compared with other in-situ conversion technology, this method has the advantages of simple equipment, high conversion efficiency, environmental protection and good economy. The law of the mutual influence among the electricity parameters, oil shale rock characteristics and the conversion effect is obtained through the heating experiments. A multi -field coupling mathematical model is established to simulate the conversion process. The mechanism of high voltage breakdown – plasma heating in situ conversion is summarized by the method of inverting and fitting.

油页岩资源量大，可以替代常规油、气的资源，成为我国能源安全的有力保障。但是，油页岩开发技术难度大，仍然需要突破原位转化的基础理论和关键技术的瓶颈。油页岩高压击穿-等离子体加热原位转化技术由固体绝缘材料高压放电机理衍生而来。其基本原理是：在油页岩目标层埋设两支耐高温电极，向两支电极间通入高压电，电极间油页岩发生放电效应，产生大量等离子体，两电极间电阻迅速降低；再向两电极间通入常压、高频电，等离子体定向移动形成电流，利用此时油页岩自身的电阻热效应加热油页岩，使干酪根裂解成油气。与其他原位转化技术相比，该技术具有设备简单、转化效率高、环保、经济性好等特点。通过高压击穿、等离子体加热试验研究，得到电力参数、油页岩岩石特性，转化结果之间相互影响的规律；建立多场耦合数学模型，模拟技术工艺过程；通过反演和拟合的方式，得出油页岩高压击穿-等离子加热原位转化的机理。

油页岩资源量大，可以替代常规油、气的资源，成为我国能源安全的有力保障。但是，油页岩开发技术难度大，仍然需要突破原位转化的基础理论和关键技术的瓶颈。研究油页岩高压击穿-等离子体加热转化机理，可以搞清两极间油页岩的放电原理，明晰电压、电频率、电流对油页岩的作用过程和规律，从而完善该技术的工艺方法和工艺流程，为该技术大规模应用提供可靠参数和理论支撑。加快油页岩的原位转化技术和基础理论研究，能够促进油页岩产业快速发展，利用页岩油补充石油，降低我国未来油气资源对外的依赖程度，满足国民经济建设的需要，保障能源供给安全。油页岩高压击穿-等离子体加热原位转化技术由固体绝缘材料高压放电机理衍生而来。其基本原理是：在油页岩目标层埋设两支耐高温电极，向两支电极间通入高压电，电极间油页岩发生放电效应，产生大量等离子体，两电极间电阻迅速降低；再向两电极间通入常压、高频电，等离子体定向移动形成电流，利用此时油页岩自身的电阻热效应加热油页岩，使干酪根裂解成油气。研究过程中建立了高压-工频实验平台，通过0-8000v高压击穿、工频等离子体加热试验研究，得到电力参数、油页岩岩石特性，转化结果之间相互影响的规律；使用各种分析仪器，研究油页岩转化前后的物化参数；使用ANSYS仿真软件建立多场耦合数学模型，模拟技术工艺过程；使用MATLAB数学软件通过反演和拟合的方式，分析油页岩高压击穿-等离子加热电压、电流等加热参数及油页岩转化结果，得出油页岩原位转化的机理。我国地下原位开采技术研究还处于起步阶段，基础研究比较薄弱，加强地下原位转化技术基础理论研究，可以快速改变传统油页岩开采模式，有效规避诸多环境和经济问题，使已有原位开采技术在可行性、经济性、环保性达到商业开采的要求。