减缓裂解炉结焦速率的分析

本文对二氯乙烷裂解炉的结焦过程进行了分析，对影响结焦的因素进行了讨论，提出影响结焦的主要因素是温度和ＶＣＭ浓度。因此，只有改善炉管内物料流的温度分布才能降低反应温度，从而获得较优的裂解结果，延长裂解炉的操作周期。     

表面状况对HK40裂解炉管结焦性能的影响研究

对两个批次的HK40裂解炉管进行研究发现,二者在裂解实验中结焦量差别明显。通过EDS、SEM对两个批次的裂解炉管分析发现,二者基体元素组成相似,但裂解炉管内表面的表面形态和元素组成相差很大,氧化铬晶须的存在是使裂解炉管结焦量减少的主要原因。采用EDS对裂解炉管出口焦炭粉末分析表明,裂解过程中结焦量大的HK40裂解炉管结焦焦体中存在大量Fe、Ni等组分。     

VCM分厂提高自产EDC纯度的几种措施

针对裂解炉进料EDC纯度低，易造成裂解炉结焦。影响正常生产，所以针对几个方面来的EDC物料，采取一些措施，改进设备，提高精馏效果，尽可能降低副产物，裂解结焦减少，提高其运转周期。     

乙烯裂解炉的结焦及其抑制措施

介绍了烃类在裂解炉中裂解的结焦机理及影响结焦的因素,国内外乙烯裂解过程中裂解炉管结焦抑制技术的进展．包括炉管表面涂层技术、最新结焦抑制剂和新型炉管等的应用。     

国产化乙烯裂解炉结焦原因分析及对策

针对武汉乙烯裂解炉实际运行情况,分析了造成裂解炉(H-005与H-006)结焦的各种原因,并针对结焦的各种情况提出了减缓结焦的措施。     

乙烯裂解炉及急冷锅炉结焦抑制技术研究进展

当前工业上普遍采用结焦抑制处理的技术防范来减少和杜绝乙烯裂解炉以及急冷炉出现结焦的问题,从而提升生产效率与安全性。立足于现状,文章首先分析了乙烯裂解炉与急冷锅炉结焦的基本原理,其次对抑制乙烯裂解炉结焦技术的发展情况进行了分析,并在最后对抑制急冷锅炉结焦技术的发展进行了解析,希望可以为结焦抑制技术的进步与发展创造条件。     

减缓裂解炉结焦的措施

本文论述了裂解炉结焦的机理及其影响因素,对装置现状进行了分析,提出了减缓裂解炉结焦的措施,以达到延长裂解炉的运行周期,提高企业经济效益的目标。     

乙烯裂解炉的结焦原理及其抑制方法

乙烯裂解炉的结焦是影响乙烯装置正常运行的一个重要因素,本文依据结焦原理介绍了使用结焦抑制剂、改善炉管材质以及炉管表面处理三种抑制乙烯裂解炉结焦的方法,并着重阐述了国内外抑制结焦的研究现状。     

裂解炉对流段结焦原因及解决方法

根据中原乙烯裂解炉对流段结焦情况，分析了影响对流段结焦的因素，提出了处理方法和预防措施。     

裂解技术发展近况

介绍了裂解技术的发展现状及发展趋势，重点介绍了裂解炉技术，裂解原料与裂解产率，抑制结焦技术以及裂解炉的热效率和大型化，控制技术等方面。     

二氯乙烷裂解管式反应器二维模拟

建立了二氯乙烷在管式反应器中进行气相热裂解的二维模型 ,模型考虑了二氯乙烷热解生成氯乙烯的主反应和生成焦前体的副反应以及气体密度变化对裂解反应的影响 .模拟计算表明 ,二氯乙烷和氯乙烯的浓度沿径向分布平坦 ;但是管内近壁面处由于存在边界层 ,始终存在着明显的径向温差 ;近管壁处始终是裂解的高速率区 ,副反应也主要发生在管壁区 .表明确定最优的炉管管径时必须考虑提高裂解速率与降低结焦速率之间的平衡 .在距进口量纲 1管程 0 .3左右的管壁处裂解速率达到最高 ;副反应速率的最大点位于出口管壁处 .与工业数据比较后发现 ,炉管出口的转化率、选择性、出口压力和温度等数据与模型预测值一致 ,表明模型具有较高的可信度     

乙烯裂解炉结焦抑制技术研究

介绍了乙烯裂解炉的结焦机理、影响结焦的主要因素和抑制炉管结焦的主要技术。     

乙烯裂解炉结焦抑制技术研究

介绍了乙烯裂解炉的结焦机理、影响结焦的主要因素和抑制炉管结焦的主要技术。     

乙烯技术发展与超短接触反应器

基于对管式炉理解解技术的发展和超短接触反应器基础研究的综述，分析了管式炉裂解技术存在的局限和超短接触反应器的技术特点以及超短接触反应器烃类裂解工艺所具有的技术优势。     

Formation of coke in thermal cracking of jet fuel under supercritical conditions

Continuous-flow reactor experiments were carried out to study coke formation from thermal cracking of home-made jet fuel RP-3 under supercritical conditions. The mechanism and precursor of coke forming were analyzed. The starting cracking temperature of RP-3 fuel was determined to be 471.8°C by differential scanning calorimetry (DSC). Temperature-programmed oxidation and scanning electron microscopy (SEM) characterizations of the stressed tubes showed that there are three different coke species including chemisorbed carbon, amorphous carbon and filamentous coke in the solid deposits. More than 90% of coke deposits are carried away by the supercritical fluid, which has strong capabilities of extraction for coke deposits and their precursors. There were 17.1 wt-% of iron and 11.1 wt-% of chromium found on the coke surface detected by energy dispersive spectroscopy (EDS) which suggests carburetion on alloy. RP-3 fuel and its cracking liquids were analyzed by GC-MS,which showed that the content of alkyl benzene and alkyl naphthalene increased evidently in cracking liquids.     

考虑切料过程的乙烯裂解炉炉群调度建模与优化

乙烯裂解炉炉群通常由多台裂解炉并行运行,将烃类原料裂解成小分子烃类化合物。由于随着裂解炉连续运行不可避免地在炉管内壁产生结焦,结焦导致裂解炉运行效率下降,所以需要对裂解炉进行周期性的停炉清焦。对于不同价格参数的多种原料不同清焦费用的多台裂解炉来说,整个乙烯裂解炉炉群系统的循环调度应是求得最优解使得收益最大化。本文对此类裂解炉炉群循环调度问题提出了一个新的混合整数非线性（MINLP）模型,相比较以前的研究该模型能够得到更好的求解多原料多裂解炉的问题,同时解决了裂解过程中切料时机选择的问题。最后,以某乙烯厂为研究实例进行切料时机的优化,优化后裂解炉全周期的运行效益显著提高,为操作人员选择最佳切炉时机提供了理论依据,说明了此模型的有效性。     

"80U"型裂解炉炉管结焦堵塞采取的措施

叙述了中国石油大庆石化公司化工一厂新区乙烯装置3台"80U"型裂解炉,由于各种原因经常发生单根炉管结焦、焦块堵塞炉管的情况,致使受限的炉管烧焦时管内焦层不能烧掉,不得不停炉更换炉管。采用单根炉管烧焦技术后,在整台裂解炉烧焦的同时,受限的炉管也能彻底烧焦合格。     

Modelling coke formation in an industrial ethane-cracking furnace for ethylene production

The development of a model for predicting coke formation in an industrial ethylene cracking furnace is described. Expressions for predicting the rates of catalytic and pyrolytic coke formation are developed and a differential equation is derived to predict changes in coke thickness with time and position. An expression is developed to account for a decline in the rate of catalytic coke formation with increasing thickness of the coke layer. The proposed coke model equations are used to extend a previously developed ethane pyrolysis furnace model that ignored coke. Three model parameters related to coke formation are estimated using industrial data to obtain reliable model predictions. Two of these parameters are coefficients that appear in the catalytic and pyrolytic coke formation rate expressions. The third is a characteristic-length parameter used to reduce the rate of catalytic coke formation as the coke layer grows. The resulting dynamic model matches the industrial data well and can be used to simulate furnace operation and predict coke thickness profiles over a variety of the operating conditions, thereby helping process engineers who plan the decoking process.     

Formation of coke in thermal cracking of jet fuel under supercritical conditions

Continuous-flow reactor experiments were carried out to study coke formation from thermal cracking of home-made jet fuel RP-3 under supercritical conditions. The mechanism and precursor of coke forming were analyzed. The starting cracking temperature of RP-3 fuel was determined to be 471.8°C by differential scanning calorimetry (DSC). Temperature-programmed oxidation and scanning electron microscopy (SEM) characterizations of the stressed tubes showed that there are three different coke species including chemisorbed carbon, amorphous carbon and filamentous coke in the solid deposits. More than 90% of coke deposits are carried away by the supercritical fluid, which has strong capabilities of extraction for coke deposits and their precursors. There were 17.1 wt-% of iron and 11.1 wt-% of chromium found on the coke surface detected by energy dispersive spectroscopy (EDS) which suggests carburetionon alloy. RP-3 fuel and its cracking liquids were analyzed by GC-MS,which showed that the content of alkyl benzene and alkyl naphthalene increased evidently in cracking liquids. __________ Translated from Petrochemical Technology, 2006, 35(12): 1151–1155 [译自:石油化工]