具有热反馈机制的炼油过程分子水平建模及基于装置间分子组成矩阵传递的系统优化

In order to regulate the quality of gasoline and diesel precisely, a kinetic model of the hydrofining process at the molecular level is proposed, and the system optimization at the molecular level is carried out. Based on the structure-oriented lumped method, the oil composition structure is recognized at the molecular level by combining with higher analytical instruments, and the matrix expression of the oil composition at the molecular level is realized. A new method for predicting the molecular structure and thermodynamic properties of petroleum hydrocarbons and their mixtures was developed based on quantitative calculation and classical density functional theory. Based on the reaction mechanism of hydrofining process, the reaction rules were formulated, the reaction network was programmed, and the molecular level reaction kinetic model of gasoline-diesel hydrofining process was constructed. The feedback mechanism of reaction heat effect on hydrofining process was studied. The molecule of sulfur-nitrogen, olefin, aromatic hydrocarbon and other pollutants in gasoline-diesel oil was revealed. The transformation rule in refining process. Standard data interfaces between different unit units were developed, and the data were transferred through molecular composition matrix. The hydrofining model was coupled with the reaction kinetics models of molecular level catalytic cracking and diesel hydroupgrading, and the molecular level process simulation and system optimization were carried out to reveal the hydrocarbon and non-hydrocarbon fractions. The synergistic transformation rule between different devices can achieve the goal of reducing consumption, improving quality and increasing efficiency.

为了对汽柴油质量指标进行精准调控，本课题拟建立分子水平的加氢精制过程反应动力学模型，并开展分子级的系统优化。基于结构导向集总方法，通过与高等分析仪器联用，在分子层面认识石油组成结构，实现油品组成分子水平上的矩阵表达。建立基于量化计算和经典密度泛函理论的分子结构与热力学性质预测新方法，实现石油烃类及其混合物性质的精准预测。基于加氢精制过程的反应机理，制定反应规则，编程建立反应网络，构建汽柴油加氢精制过程的分子水平反应动力学模型，研究反应热效应对加氢精制反应过程的反馈机制，揭示汽柴油中硫氮、烯烃、芳烃和其他污染物分子在精制过程中的转化规律。开发不同单元装置间的标准数据接口，通过分子组成矩阵进行数据传递，将加氢精制模型与前期建立的分子水平催化裂化、柴油加氢改质等过程反应动力学模型相耦合，开展分子级的过程模拟和系统优化，揭示烃类和非烃类分子在不同装置间的协同转化规律，实现全厂降耗提质增效的目标。

石化行业的基础工业软件主要被Aspen等国外公司垄断，对外依存度极高。石化行业软件开发需要破解的关键难题是构建石油加工过程准确可靠的反应动力学模型以及不同装置间的耦合问题。传统馏分集总反应动力学模型对油品体系的描述较为粗糙，不涉及分子水平的信息，无法实现不同装置模型间有效的物流信息传递。.本研究基于量化计算和经典密度泛函理论，建立了油品分子的结构-性质模型。基于结构导向集总方法，结合催化裂化、加氢精制等过程中油品分子的组成特点和结构特征，设计了24个结构单元来描述烃类和非烃类分子，根据原料的组成和性质构建了4148行×25列的催化裂化原料分子组成矩阵。基于反应类型和反应机理，分别制定了96、24、34和34条反应规则来描述催化裂化、汽油加氢精制、柴油加氢精制和柴油加氢改质过程的分子反应行为，构建了包含约180000个反应的反应网络。结合反应速率常数，采用改进的Runge-Kutta法进行求解，构建了分子水平的催化裂化、加氢精制、加氢改质等过程的反应动力学模型。根据模型计算获得的产物分子组成矩阵及结构-性质预测模型，计算了产物中硫氮、烯烃、芳烃等典型分子含量以及汽油辛烷值、柴油十六烷值等产物性质指标。开发了不同单元装置间的标准数据接口，通过分子组成矩阵在不同装置模型间进行数据传递，将关联单元装置进行耦合模拟，构建了分子组成矩阵-单元装置-装置耦合模拟三个层次的软件体系。开发的石油加工过程模拟与优化软件有助于解决国外对我国石化行业基础工业软件“卡脖子”的问题。.利用软件进行分子级的耦合过程模拟，揭示了汽柴油中硫氮、烯烃、芳烃和其他污染物分子在催化裂化-加氢精制-加氢改质过程中的转化规律，并对耦合过程开展了分子级的系统优化。以原料组成和操作条件为决策变量，以国六标准规定的汽柴油中特定分子或组分含量、性质指标要求为约束条件，以精制油收率为优化目标，实现硫氮、芳烃、烯烃在不同阶段的合理转化，制定了催化裂化-加氢精制-加氢改质过程降耗、提质、增效的优化策略，实现了对汽柴油质量指标的精准调控。