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本文主要分析了乙烯装置裂解炉在日常操作中由于操作压力,裂解温度,炉管渗碳,炉管检修等操作过程中的控制不当导致裂解炉辐射段炉管破损的原因,并且针对各种原因提出了相应的对策。 相似文献
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USC型乙烯裂解炉炉膛燃烧过程数值模拟 总被引:6,自引:0,他引:6
以广州石化的USC型乙烯裂解炉辐射段为几何模型,采用计算流体力学的方法对计算域进行几何建模和网格划分,用标准的k-ε湍流模型、非绝热的简化PDF燃烧模型和离散坐标辐射传热模型对炉膛内的燃烧和辐射状况进行三维全尺寸数值计算,以研究炉膛内的燃烧、传热和烟气流动情况.计算得到的流场合理,温度、浓度分布与实际吻合良好,说明对裂解炉辐射段的数值模拟计算是成功的.该模拟计算验证了所建立的乙烯裂解炉炉膛燃烧反应数学模型的可靠性和合理性,并为优化设计裂解炉结构提供理论参考. 相似文献
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某公司裂解炉原设计原料单一,运行周期偏短,经过多年运行,辐射炉管表面渗碳严重,已达到使用寿命。通过对该裂解炉辐射管结构进行改造,降低炉管热强度,减少结焦,并在对流段增设模块,增加换热面积,降低排烟温度,达到既能裂解石脑油又能裂解轻烃原料,延长裂解炉运行周期,提高热效率的目的。 相似文献
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针对裂解炉管弯头处流体运动状态变化的特点,采用柱塞流反应器(PFR)与串联全混流反应器(CSTR)组合的反应器模型,耦合计算了炉膛传热和辐射段炉管内的烧焦过程.将烧焦时焦炭表面氧分压、烧焦速率、炉管出口气体温度和碳氧化物含量、焦炭层厚度等影响的模拟结果与无返混的PFR模型的模拟结果进行了比较.结果表明:两种模型模拟的炉管出口气体温度和碳氧化物含量均与生产实际基本相合,但有返混的模型能更准确地描述烧焦结束时残碳在管内的分布特点. 相似文献
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Coupled simulation of combustion with heat transfer and cracking reaction in SL-Ⅱ industrial ethylene pyrolyzer 下载免费PDF全文
采用计算流体力学(CFD)方法对SL-Ⅱ型工业乙烯裂解炉辐射段炉膛内的燃烧传热及管内石脑油裂解反应过程进行耦合模拟,建模及耦合求解在CFX中完成。计算时采用标准k-ε双方程湍流模型、旋涡耗散/有限化学速率(EDM/FRC)燃烧模型和离散传播(DT)辐射模型,其中介质辐射特性采用多灰气加权模型;石脑油裂解反应采用Kumar分子反应模型,流体流动方程组由全隐式的耦合算法求解。模拟结果与工业数据吻合良好,验证了模型的可靠性。结果表明,管内裂解产物丙烯和丁烯收率先增后减,甲烷和乙烯收率一直增大;出口管外壁温度沿管长分布因侧壁烧嘴的加入而更加均匀;炉膛中部的回流区使该区温度更加均匀;裂解炉结构的非对称性引起烟气流速分布不对称,进而导致后墙上侧壁烧嘴的供热效率相对前墙侧较低,本文模拟结果为裂解炉进一步设计与改造提供理论指导。 相似文献
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SRT-Ⅳ(HS)型裂解炉辐射段炉管和对流段原料/稀释蒸汽混后炉管的结焦,可以通过空气/稀释蒸汽的烧焦来清除,而对流段原料/稀释蒸汽混合前原料在预热管中结焦的现象时有发生,却没有较理想的解决办法。中原乙烯首次尝试把对流段热管割开,从而准确地观察到原料/稀释蒸汽混合前预热管的结焦情况。本文的目的在于描述裂解炉对流段炉管的结焦情况及处理措施,以供各乙烯生产厂参考。 相似文献
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乙烷裂解炉安全烧焦及条件优化 总被引:1,自引:1,他引:0
采用耦合炉膛和炉管传热的计算方法,模拟KTI—SMK型裂解炉的烧焦过程。首先对恒定炉管入口烧焦气流量和温度模式的烧焦程序进行安全烧焦条件的计算,并用复形调优法计算出优化的烧焦条件为水蒸气流量1861kg/h,空气流量597kg/h,炉管人口温度626℃,烧焦时间8.2h。随后验证了该操作条件,得到管壁最高温度为1047℃,管内残炭量和烧焦时间分别低于目前装置烧焦程序模拟结果。 相似文献
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蒋学良 《化学工业与工程技术》2003,24(2):38-40
对发生失效破裂的炉管进行了宏观形貌分析、断口形貌分析、金相分析、有限元应力分析等 ,得出导致炉管破裂的主要原因是炉管在制造过程中产生缺陷引起的应力集中和特定的腐蚀环境共同作用下产生应力腐蚀断裂。 相似文献
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M. F. Tse 《应用聚合物科学杂志》2007,103(4):2183-2196
Ozone cracking and flex cracking of crosslinked elastomer blends of brominated isobutylene/para‐methylstyrene copolymer (BIMSM) and unsaturated elastomers, such as polybutadiene rubber (BR) and natural rubber (NR), are studied. This saturated BIMSM elastomer, which is a terpolymer of isobutylene, para‐bromomethylstyrene, and para‐methylstyrene, functions as the ozone‐inert phase of the blend. Ozone cracking is measured by the failure time of a tapered specimen under a fixed load in a high severity ozone oven, whereas flex cracking is ranked by the De Mattia cut growth. The ozone resistance of BIMSM/BR/NR blends is compared to that of a BR/NR blend (with or without antiozonant) at constant strain energy densities. The effects of the BIMSM content in the blend, the structural variations of BIMSM, and the network chain length between crosslinks on these two failure properties, which are important in crosslinked compounds for applications in tire sidewalls, are discussed. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 2183–2196, 2007 相似文献
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通过对大庆乙烯装置80-U型裂解炉出口温度(COT)测量方式进行优化及改进,提高了对裂解深度的控制程度,进而改善了裂解炉日常的运行状况,达到了提高乙烯产品收率的目的。 相似文献
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András Angyal Norbert Miskolczi Antal Tungler László Vida 《Fuel Processing Technology》2010,91(11):1717-1724
In this work the utility of new possible petrochemical feedstocks obtained by plastic waste cracking has been studied. The cracking process of polyethylene (PE), polyethylene-polypropylene (PEPP) and polyethylene-polystyrene (PEPS) has been carried out in a pilot scale tubular reactor. In this process mild reaction parameters has been applied, with the temperature of 530 °C and the residence time of 15 min. The produced hydrocarbon fractions as light- and middle distillates were tested by using a laboratory steam cracking unit.It was concluded that the products of the mild cracking of plastic wastes could be applied as petrochemical feedstocks. Based on the analytical data it was determined that these liquid products contained in significant concentration (25-50 wt.%) of olefin hydrocarbons. Moreover the cracking of polystyrene containing raw material resulted in liquid products with significant amounts of aromatic hydrocarbons too. The steam cracking experiments proved that the products obtained by PE and PEPP cracking resulted in similar or better ethylene and propylene yields than the reference samples, however the aromatic content of PEPS products reduced the ethylene and propylene yields. 相似文献
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通过流动管反应器对碳氢燃料RP-3在超临界条件下的热裂解及引发裂解进行了实验,对两种条件下的燃料吸热能力及传热特性进行了对比分析,并对裂解产物进行了采样分析。结果表明,引发裂解降低了燃料的裂解起始温度,在一定温度区间内提高了燃料的裂解率,从而有效提高了燃料热沉,在相同热通量条件下,降低了燃料温度,并降低了加热段壁面温度。对流换热受化学反应及物性变化的影响,燃料裂解吸热可增强换热,而大量气态产物的生成会降低换热,因此,裂解反应的增强不一定增强换热。 相似文献
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Behavior of catalytic cracking reactions of particle cluster in fluid catalytic cracking (FCC) riser reactors was numerically analyzed using a four-lump mathematical model. Effects of the cluster porosity, inlet gas velocity and temperature, and coke deposition on cracking reactions of the cluster were investigated. Distributions of temperature, gases, and gasoline from both catalyst particle cluster and an isolated catalyst particle are presented. The reaction rates from vacuum gas oil (VGO) to gasoline, gas and coke of individual particle in the cluster are higher than those of the isolated particle, but it reverses for the reaction rates from gasoline to gas and coke. Less gasoline is produced by particle clustering. Simulated results show that the produced mass fluxes of gas and gasoline increase with the operating temperature and molar concentration of VGO, and decrease due to the formation of coke. 相似文献
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提出一种基于K均值聚类的多群竞争粒子群优化算法(MSCPSO),该算法避免陷入局部最优,提高了算法的全局搜索能力。同时利用MSCPSO训练RBF神经网络并建立裂解产物的在线预测模型,研究一种集成MSCPSO-RBFNN过程建模的裂解深度智能优化控制方法。该方法以实现乙烯和丙烯收率之和最大化为目标函数,把满足优化目标的裂解深度作为深度控制器的输入,并与裂解炉出口温度先进控制系统集成,实现裂解深度的平稳控制。实际应用效果表明,提高了乙烯和丙烯的收率,裂解深度控制更加稳定,该方法具有良好的适应性、稳定性。 相似文献