全循环油页岩干馏炉内流动-传热-传质特性与规律研究

As a new retorting technology of China’s own R&D, the gas full circulation oil shale retort has substantially promoted the development of oil shale retorting industry in China. However, the thermal and retorting process of the retort, including the rules of materials flow, heat transfer, pyrolysis reactions and mass transfer, have not been investigated, which restricting the further development, promotion and industrial applications of the new retorting technology. To ascertain the characteristics and rules of flow, heat and mass transfer process in gas full circulation retort, this project plan to investigate the formation characteristics and secondary reactions rules of products from the pyrolysis of oil shale firstly through a series of retorting experiments. Then, a three-dimensional mathematic model with flow, heat transfer and mass transfer of gas full circulation oil shale retort is established, which is verified through cold physical modelling experiments of the flowing rules of oil shale and heat carrier, and the on-site measurements of retorting, to investigate the characteristics of products generation, flows, heat and mass transfer process in the retort, to optimize the technological parameter of retorting process and explore the feasibility of increasing the retort capacity through magnifying the retort body. The aim of this project is to uncover the microcosmic law of products formation and evolution from oil shale pyrolysis, expand the research methods and provide theoretical supports for the development and application of gas full circulation oil shale retort. Besides, this project can provide theoretical basis and method for the mathematic model building of other oil shale retorting technology.

全循环油页岩干馏工艺是近年来我国自主研发并工业化运用的新型油页岩干馏技术，有力推动了我国油页岩干馏工业的发展。然而，全循环干馏炉内的热工和反应过程，包括气-料流动规律、温度分布规律、热解产物生成规律和质量传递过程等尚未探明，成为限制该技术工艺优化、扩容增产等进一步发展和推广的主要瓶颈。本项目以全循环油页岩干馏炉为研究对象，首先通过干馏试验研究，探明干馏炉内油页岩热解产物主要组分生成动力学和二次反应规律；在此基础上，通过构建全循环干馏炉流动-传热-传质多耦合三维数学模型，结合干馏炉气体和物料流动规律冷态物理模拟试验和现场中试试验研究，探明干馏炉内油页岩和热载体的流动-传热-传质特性与规律，优化“分级干馏”工艺，探讨扩容增产的可行性。本项目旨在揭示油页岩热解产物形成演变微观规律，扩大全循环干馏技术研究手段，为全循环干馏技术推广及其他干馏炉流动-传热-传质数学模型建立奠定理论和技术基础。

本项目研究了吉木萨尔油页岩热解产物主要组分生成动力学，在此基础上探究了热解产物组分在干馏炉内的二次反应规律；最终建立了全循环干馏炉流动-传热-传质多耦合三维数学模型，并分析了干馏炉内的热工特性。为揭示油页岩热解产物形成演变微观规律、扩大全循环干馏技术研究手段提供了理论基础和研究思路。. 采用扫描电镜、核磁共振波谱分析、傅里叶红外分析等检测手段揭示了油页岩热解过程中的孔隙结构演变过程、碳结构骨架变化规律、官能团结构演变规律、矿物质分解规律等热解特性；采用热重-质谱联用技术、热重-傅里叶红外联用技术等检测手段探究了吉木萨尔油页岩的热解特性和产物生成特性，并求解了热解动力学和产物生成动力学；吉木萨尔油页岩有机质在不同的热解阶段具有不同的热解机理；H2、H2O、CO、CO2、SO2、CH4、C2H4、C3H4、C12H18、Oil等35种热解产物的生成动力学参数为热解过程数值模拟提供了研究基础。. 采用铝甑干馏实验研究了升温速率、热解终温、保温时间等参数对粉末油页岩热解产物产率的影响；采用热解平台研究了0-10、10-20、20-30、30-40、40-50mm油页岩在不同堆积高度下的热解特性；并基于元素分析、红外光谱分析、核磁共振分析、气相色谱-质谱分析等检测手段分析了上述热解参数对页岩油、热解气、半焦成分的影响，揭示了升温速率、热解终温、保温时间、物料尺寸、床层高度等参数对热解产物二次反应的影响规律。. 建立了全循环油页岩干馏炉内气-料大尺度流动传热传质多耦合数学模型，并验证了数学模型的准确性。采用数学模型探究了干馏炉内的流动特性、传热特性、热解产物生成特性。