稠油水热裂解生成硫化氢反应机制研究

In the process of steam injection recovery, H2S and other acid gases are produced from aquathermolysis reactions between steam and heavy oil in reservoir. The mainly work of the project is to discover the formation mechanism of H2S in aquathermolysis reactions. According to the theory of thermal recovery of heavy oil and chemical thermodynamics, the project describes the sulfur mode of occurrence in heavy oil aquathermolysis reaction primarily. And it explores the generate path of H2S in reaction process of sulfur organic compounds, such as hydrolysis, hydrodesulfurization and water gas shift reaction and confirms the reaction mechanism and establishs H2S formation reaction kinetics model. Then it will combine with in situ heavy oil samples to illustrate the influence rules of generation of H2S in aquathermolysis and finally to explore the methods of controlling the formation of H2S. It provides a theoretical basis for forecasting the formation of H2S in the heavy oil thermal recovery process, controlling the formation path of the H2S and eliminating the hazards of H2S scientifically. And it will enhance to understand the heavy oil thermal recovery, thermochemistry and chemical industry on the molecular scale.

针对注蒸汽开采过程中蒸汽与稠油之间的化学反应产生H2S等酸性气体的现象，开展稠油水热裂解反应的H2S生成机制研究。从稠油热采理论和化学反应动力学出发，基于稠油含硫化合物中硫化学赋存形态的表征，探索含硫有机物水解、加氢脱硫和水气转换等反应过程生成H2S反应路径，明确水热裂解生成H2S的反应机制并构建反应动力学模型，结合现场稠油油样阐明水热裂解H2S成因影响规律，探寻控制H2S生成反应路径的方法，为科学地预测含硫稠油油田热采H2S的生成量、控制H2S生成路径及消除H2S危害提供理论基础，提高稠油热采、热化学、化工等领域的分子尺度认识平。

针对注蒸汽开采过程中蒸汽与稠油之间的化学反应产生H2S等酸性气体的现象，本项目从稠油热采理论和化学反应动力学出发，采用实验与模拟相结合、宏观与微观相结合的方法，首先采用同位素追踪、元素分析、四组分分析等研究了水热裂解反应物和生成物中硫的赋存形态，并基于密度泛函理论，构建了水热裂解反应物中硫的赋存形态表征模型。其次，通过不同实验条件下的反应剂和反应产物化学分析，分析了水油比、温度、时间、过热度、过冷度等因素对水热裂解反应机制的影响及反应路径的改变，揭示了不同因素对H2S生成特性的影响。最后，在实验基础上，建立了稠油水热裂解生成H2S的化学反应动力学模型，将不同种类的催化剂引入加氢脱硫反应体系中，开展了稠油水热裂解过程中加氢脱硫反应的微观机理研究，揭示了不同催化作用下典型化合物加氢至最终脱硫的最优路径和反应机理。本项目深入探索了稠油热采次生H2S的生成机理及影响机制，对于H2S产量的预测和H2S危害的控制具有重要意义。同时，本项目研究结果为稠油开采过程中深度脱硫降黏、原位改质降黏以及明确蒸汽吞吐、蒸汽驱、蒸汽重力辅助泄油、火烧油层中H2S的成因提供了可靠的理论依据。