可调循环比的延迟焦化工艺

传统的延迟焦化流程难以实现低循环比操作，而采用可调循环比流程可根据原料性质、产品要求、处理量的情况选择合适的循环比，尤其在超低循环比下更显优点。通过生产操作实践证明，可调循环比工艺流程提高了延迟焦化装置操作的灵活性。     

延迟焦化加热炉辐射进料结焦性能的研究

通过对不同循环比延迟焦化辐射进料性质分析和不同循环比辐射进料的热稳定性试验，得出了增加循环比可以降低辐射进料中的沥青质含量，提高辐射进料的芳烃与沥青质比，减缓加热炉管结焦的结论。向辐射进料中加入富含芳烃的催化裂化澄清油不仅可以提高辐射进料的沥青质含量和芳烃与沥青质比，而且可以提高辐射进料的临界分解温度，抑制沥青质和甲苯不溶物的生成，缩短辐射进料分解后在低温高压炉管范围内的流动距离和停留时间，有利于进一步减轻焦化炉管的结焦。     

延迟焦化分馏塔内筛管结焦分析与改进

分析了分馏塔内筛管结焦原因，提出了改进方案，解决了因筛吉焦堵塞影响装置长周期生产的难题。     

延迟焦化装置分馏塔塔底防结焦技术改造

针对中国石化天津分公司延迟焦化装置分馏塔塔底的结焦问题,采用蜡油与焦炭塔油气直接换热的方法,对装置进行了改造。结果表明,改造后分馏塔蒸发段温度提高了１０℃;蜡油残炭质量分数增加了０．２０５个百分点,密度增加了６．７５ｋｇ／ｍ３,表明改造后蜡油质量略有降低;装置循环比平均值下降了０．０８个百分点,加工量提高了１３５ｔ／ｄ,液体收率增加了１．１８个百分点,装置经济效益得到提高。     

延迟焦化传统流程与可调循环比流程的工艺比较

通过对某公司1.2Mt/a延迟焦化装置传统工艺流程和1.60Mt/a延迟焦化装置的可灵活调节循环比两种流程的比较分析认为,后者具有灵活、直观的优点,对于防止分馏塔底结焦、改善辐射泵的运行环境有着独特的效果,在加工劣质渣油方面具有优势。     

延迟焦化装置分馏塔循环比的优化

 在一定的加工方案下，延迟焦化装置分馏塔循环比对装置的产品分布、产品质量及能耗有着重要的影响，是焦化装置的关键操作变量。在大量收集现场数据的基础上，运用流程模拟、能量优化及数值回归等技术手段，从产品分布、能耗和效益3个方面分别研究了循环比的影响规律，建立了求解最优循环比的一般方法，即以循环比为优化变量，以包括产品收益和能耗成本在内的装置效益为目标函数，通过最优化计算得到最优循环比。实例应用表明，该方法能较好地指导生产，按其优化的循环比操作，处理量1.2M t/a的焦化装置可提高经济效益3.516×10⁶ RMB Yuan/a。     

延迟焦化传统流程与可调循环比流程比较

延迟焦化装置是重油加工的主要装置之一，具有工艺技术成熟，投资和成本本其他渣油加工工艺相对较低，效益大，对原料要求低的特点，     

延迟焦化加热炉炉管结焦原因分析及对策

通过对乌鲁木齐石化公司不同时期加工的延迟焦化原料的四组分含量及金属含量的变化分析,以及对辐射炉管结焦前后加热炉操作参数的对比分析,得出延迟焦化原料是一种饱和烃、胶质及沥青质含量高、芳烃含量低的易结焦渣油,在操作中宜采用较大循环比来提高芳烃与沥青质的比例,保证辐射炉管内冷油流速,控制好炉管壁温度,减缓加热炉炉管结焦,同时要对原料性质进行监控分析。     

延迟焦化装置炉管结焦原因分析及对策探讨

结焦是影响焦化装置长周期运行的重要因素，从结焦反应机理和结焦体的形成过程出发，对焦化装置结焦原因进行分析，提出抑制或延缓结焦的措施。     

可调循环比在焦化改造中的优势

常规延迟焦化的循环比的调节幅度较小,限制了装置的灵活性,武汉石化利用调循环比工艺流程对延迟焦化装置进行改造,投资120万元将装置的加工能力从40×104t/a提高的100×104t/a。结果表明,可调循环比工艺流程液收高,焦碳产率低,操作灵活,适应性强。     

延迟焦化装置18h生焦周期运行分析

为提高渣油加工能力和轻质油收率,发挥1.0 Mt/a延迟焦化装置的潜能,在现有设备、工艺流程不作任何改造的情况下,将生焦周期由20 h缩短至18 h。本文分析了缩短生焦周期对装置运行的影响,介绍了产品分布、装置能耗的变化情况。缩短生焦周期不仅有效提高了装置处理量(装置生产负荷达到130%)、液体产品收率以及轻质油收率,而且降低了装置能耗,实现了挖潜增效的目标。     

Performance of Additive JJZ-1 on Antifouling and Liquid-Improving in Delayed Coking Process

Abstract

Based on an antifouling and liquid-improving mechanism, the additive JJZ-1 was developed. The experimental results indicated that the additive JJZ-1 had evident effect on antifouling and liquid improving. Adding 100 ~ 400 μg · g^?1 additive JJZ-1 into five vacuum residues, the formation of foul in coking furnace tube can effectively reduced by 0.21 ~ 0.22%. The liquid oil yield increased by 1.50 ~ 1.68% in the delayed coking process. The coke yield and gas yield decreased by 0.80 ~ 1.10% and 0.55 ~ 0.81%, respectively. The characteristics of JJZ-1 additive were analyzed, and the mechanism for antifouling and liquid-improving was discussed.     

Co-processing Vacuum Residue with Waste Plastics in a Delayed Coking Process:Kinetics and Modeling

Thermal upgrading of vacuum residue mixed with waste plastics was studied in a laboratory scale delayed coking unit.The model of feed thermal decomposition was set up and the first order reaction kinetics was used to predict products distribution during the coking process.The distillate yield was higher(70%) for the vacuum residue/polystyrene(VR/PS) feed system and the vacuum residue/low density polyethylene(VR/LDPE) feed system.The resulted distillate yield was separated into fractions according to their boiling points,with gasoline and diesel being our fractions of concern.The activation energy was higher for gasoline production(around 60 kcal/mol) varying with the type of feed system,while it was 33 kcal/mol for diesel fraction.The regression coefficient R was 0.990.     

Increasing Liquid Yield and Diesel Fraction in Delayed Coking Process： Mechanism of Liquid Formation

The thermal upgrading of two residual oils tory-scale continuous delayed coking unit. The goal with different characteristics was studied in a labora- was to investigate the influence of the process vari- ables such as temperature, reaction time and additive on liquid yield and products distribution. A maximum liquid yield of 73% was achieved compared to 69% with the commercial unit. This yield was even increased to 75% under the effect of an additive. The fractionation of liquid oil by simulated vacuum distillation showed a high yield of diesel （46.9%）, compared to 28% for the commercial unit.     

延迟焦化增加液体收率助剂的研究及应用现状

概述了提高延迟焦化装置液体收率技术措施，如在焦化进料中加重芳烃或重芳油，加入抑制生焦的金属催化剂，添加增加液体收率的助剂及优化操作条件等。介绍了延迟焦化增加液体收率助剂的作用机理，对延迟焦化增加液体收率助剂的国内外研究及应用状况进行了综述。     

延迟焦化装置分馏塔侧线取热优化

某公司延迟焦化装置分馏塔侧线循环取热不充分,导致分馏塔热量过剩,整体温度高于设计值,影响产品质量和下游设备的正常运行,造成能量浪费。为解决该问题,运用Aspen Plus软件,采用合适的模拟策略,建立了分馏塔系统模型,分析了分馏塔的用能情况。通过流程模拟和正交试验法,以渣油换热终温为目标变量,优化得到了各侧线循环流量的最佳组合。结果表明,增加柴油循环和塔底循环油循环流量、降低顶循环、中段循环和重蜡油循环流量,可以将减压渣油换热后的温度从295.8℃提高到306.6℃,减少加热炉燃料气耗量约275.02 Nm³/h,提高了分馏塔用能效率,降低了装置能耗。     

Causes Leading to Formation of Shot Cokes and Measures for Its Prevention in Super Viscous Oil Delayed Coking Unit

Shot cokes are frequently formed in the delayed coking unit treating the super viscous oil at PetroChina＇s Liaohe Petrochemical Company. Considerable work has been carded out to avoid the formation of shot cokes. The test results obtained have shown that the property of super viscous oil has played a key role in the formation of shot cokes. After adjusting and optimizing the process indices the operating regime of the delayed coking unit at a throughput of 118t/h of the super viscous oil is specified as follows： a reaction temperature of 498-502℃, a reaction pressure of 0.17-0.25 MPa, a recycle ratio of 0.5-0.6 and a fractionation tower bottom temperature of 355-365 ℃. In the meantime, the delayed coking process has adopted measures to enhance pre-fractionation of the feedstock to rationally remove light fractions and maintain a steady gas velocity in order to avoid the formation of shot cokes.     

沸腾床渣油加氢-焦化组合工艺探讨

针对劣质渣油加工,分别采用沸腾床渣油加氢-焦化组合工艺与单独焦化工艺两种技术路线进行探讨,以选择其适合的加工技术路线。结果表明,劣质渣油原料经沸腾床加氢,产品杂质含量显著降低。在双反应器温度基准+5/ 基准+5、基准空速条件下,劣质渣油加氢产品的S、Ni、V含量分别下降了90%、95%、99%。与劣质渣油原料相比,沸腾床加氢减压渣油的性质得到极大改善。与单独焦化工艺相比,采用组合工艺加工劣质渣油,总液体产率提高了13.57%,增产高附加值产品的能力明显提升,从而大幅度提高经济效益。同时,该组合工艺具有改善油品稳定性、原料适应性广、工艺灵活等明显优势, 是提高原油资源利用率的较佳方案。     

基于优化RVFLN模型的延迟焦化开工线H2S浓度预测

分析了延迟焦化开工线腐蚀的原因,其主要腐蚀形式为低温湿硫化氢（H2S）腐蚀,集成工业现场异构数据库系统,建立了基于随机权神经网络（RVFLN）的焦化装置开工管线内H2S浓度的数据驱动预测模型。首先用主成分分析法对输出变量进行降维;然后根据相关系数大小筛选影响开工线内H2S浓度变化的主要影响因素,将其作为模型输入用来训练模型;为获得更好的泛化性能,将RVFLN的随机权重控制在［0,1］之内,建立小规范随机权重神经网络（SNRVFL）;最后用现场数据对模型进行测试评估。结果表明,与PLSR、BPNN、SVR模型对比,优化后的RVFLN模型在预测精度和计算速率上都有较好表现,该模型适用于焦化装置开工管线内H2S浓度的实时在线预测,可为延迟焦化装置压力管道内的流动腐蚀风险评估提供基础数据。