【作者】 叶剑云；

【导师】 高学农；

【作者基本信息】 华南理工大学 ， 化学工程， 2010， 硕士

【摘要】 随着世界经济的快速发展,世界各国对石油,特别是轻质的燃料油的需求量猛增,然而世界的原油储量中,浅层好开采的轻质低硫原油越来越少,深层难开采的重质含硫原油越来越多,并且世界各国更加注重环保,对汽、柴油等轻质燃料油的品质要求越来越高。因此加氢裂化这一重要炼油手段越来越受重视,生产能力逐年上升。加氢裂化装置由于涉及高温高压反应,装置能耗较高,而国内的加氢裂化装置的用能水平更是参差不齐,用能水平最高与最低的装置能耗相差达两倍以上,节能潜力较大。本文以加氢裂化基准工艺流程(单段串联一次通过、冷高分)为研究对象,建立工艺流程模拟模型,通过模拟模型参数调整,如理论塔板数的折算,反应产物物性的调整等,使模拟能够准确再现实际生产情况。在此基础上,对装置进行“三环节”能量分析和分析,发现现有工艺流程的用能瓶颈在于冷高分部分,因为反应产物重复冷却、升温,造成极大的能量损失,限制了反应热进入分馏系统,导致分馏系统加热炉负荷过高,此外,反应流出物压力能没有回收利用也造成电能严重浪费。针对以上用能瓶颈,提出两种用能优化策略:基于冷高分流程用能优化和基于热高分流程用能优化。基于冷高分流程的用能优化策略是结合分馏系统优化,对换热网络进行优化改进以及通过提高回收环节的能量回收利用效率来减少转有效转换能。主要优化措施包括:分馏塔优化,脱丁烷塔优化,结合分馏系统改进的高、低压换热网络优化以及压力能的回收利用。通过模拟分析,改进后取得一定的节能效果,装置能耗减少约4kgEO/t。基于热高分流程的用能优化策略是通过反应分离等核心工艺流程的改进,把冷高分流程改为热高分流程,并对分馏系统流程进行优化改进,以及结合分馏系统的换热网络优化设计,通过工艺利用环节的优化从源头减少工艺总用能。通过模拟分析,装置能耗降低10kgEO/t以上。更多还原

【Abstract】 With the rapid development of the world economy, the demand for light fuel oil, especially the high quality light fuel oil, increases rapidly. In the world’s crude oil reserves, the shallow less sulfur and light crude become less and less, remaining the high sulfur heavy crude oil. While more and more attention was paid to environmental protection, the quality requirements of light fuel oil, such as gasoline and diesel is becoming higher and higher. Therefore, hydrocracking, such an important refining mean for processing heavy oil and producing high quality light fuel oil, is getting more and more attention, and the processing capacity of hydrocracking is increasing annually.Hydrocracking is a high energy consumption process as it involves high pressure and high temperature reactions. The energy-use level for domestic hydrocracking units is uneven, and the difference between the highest and the lowest energy-use level is up to more than two times, which indicates that the energy-saving potential is very large. Nowadays, the energy situation is so severe that it is important to save energy for hydrocracking units.In this paper, a hydrocracking benchmark process (single-stage, single pass, cold high pressure separation flowsheet) was used as the research object, to establish the process simulation, and adjust the parameters of simulation model (such as conversion of the theoretical plate number, the adjustment of properties of the reaction product), so the simulation can accurately reproduce the actual process. Based on the simulation, energy analysis and exergy analysis with "three-link model" were conducted. The results obtained show that the energy-use bottlenecks for the existing process flow is the cold high pressure separation flowsheet, in which the reaction products repeat the process of cooling and heating, which resulting in a great energy loss, and limiting the reaction heat getting into the distillation system.A higher distillation system heating load is required for the distillation separation. In addition, the high pressure energy of the high-temperature reaction products is not recycled also. Against to this bottleneck, two energy saving and optimizing strategies was proposed. One is based on the cold high pressure separation process and the other is based on hot high pressure separation process.The optimization strategy based on cold high pressure separation process is optimizing the heat exchanger network which combined with distillation system optimization, to improving the recovery part of the energy recovery efficiency to reduce energy conversion part of the output energy. The main optimization measures include: optimization of distillation tower, optimization of de-butanizer tower, optimization of the heat exchanger network which combined with the distillation system optimization and pressure energy recovery. Through simulation, the improved energy efficiency decreases the energy consumption by about 4kgEo/t.The optimization strategy based on cold high pressure separation process is to completely change the existing process, and improved distillation system optimization processes, as well as heat exchanger network optimization design. The energy save is obtained by reducing the total process energy consumption in fundamental aspects. The simulation results show that it has at least 10kgEO/t save potential by reduce fuel use.更多还原