共查询到20条相似文献,搜索用时 93 毫秒
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制氢装置转化炉炉管花斑原因分析及处理措施 总被引:1,自引:0,他引:1
2010年中石化洛阳分公司石化制氢装置四开三停,并且一直处于较低加工负荷下运行(30%左右)。作为装置核心的转化系统,在这个过程中受到了较大的影响。目前转化催化剂已经出现大面积局部结炭,表观现象就是炉管顶部到中部出现大面积花管,并且个别炉管已出现了"红管"现象。针对目前的情况从原料气性质到装置运行情况进行了分析,并探讨了炉管花斑后可能带来的影响,以及针对花斑及红管的处理措施。 相似文献
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介绍了合成氨装置一段炉炉管出现的"红管"超温现象,对炉管超温的原因进行阐述,并提出了处理对策。 相似文献
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《中国石油和化工标准与质量》2016,(23)
本文对制氢II套转化炉炉管温差增大的问题进行分析,找出了引起炉管温度温差大的原因:(1)制氢二套转化炉加工量长期处于低负荷,60根炉管存在偏流现象;(2)催化剂装填不规范,导致炉管压降存在偏差,反应不均匀;(3)使用过程操作不当使得催化剂压降增大,造成炉管偏流,温差偏大。车间有针对性地进行改进操作,提出增大水碳比,重新更换装填压降比较大的发生红管的炉管催化剂,加强联锁的控制保护催化剂完好性的措施,确保制氢转化炉炉管温差得到有效控制,并取得良好经济效益。 相似文献
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介绍了高桥石化制氢装置的两起设备故障:F102转化炉红管和M221、M222、N223喷水减温器开裂。通过故障分析得出导致故障的原因,提出了同类设备的操作原则和改进措施。 相似文献
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对橡胶冷喂料挤出过程喂料段固体输送率(Q)的影响因素进行了理论分析及实验研究,讨论了喂料段机筒温度(Tb)、螺杆转速(n)和胶料物理性能对摩擦系数(f)及Q的影响,预测了喂料段长度,综合分析了摩擦因素与胶料性能对喂料效率的作用。结果表明:Tb对冷喂料挤出的胶料与筒壁的摩擦系数有一定影响,Tb最佳值为40~50℃。红管胶与垫带胶的邵尔A型硬度较高,容易在喂料口打滑,对Q有影响。拉伸强度较小的红管胶,不易形成喂料返胶,但容易形成饥饿喂料。拉伸强度较大的普通内胎胶及胎面胶,在螺杆喂料段输送能力较低时,能形成喂料返胶。 相似文献
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1概述一段转化催化剂活性的高低不仅影响一段炉出口甲烷含量的高低,而且还会改变整个合成氨系统的生产条件,影响合成氨的产量。催化剂结盐是影响催化剂活性的重要因素。一段转化催化剂结盐会对生产带来以下不利因素:(1)包裹催化剂表面,堵塞催化剂孔洞,降低催化剂活性,从而降低一段转化率。(2)部分堵塞一段炉催化剂层直至整根转化管,使转化管阻力增大,引起部分转化管气体流量减少直至气流完全不通,造成转化管红管。催化剂结盐严重时会使生产陷入困境,转化管材质在长期高温状态下发生金相转变,从而缩短转化管寿命,甚至发生转… 相似文献
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CO2 methanation: Optimal start‐up control of a fixed‐bed reactor for power‐to‐gas applications 下载免费PDF全文
Jens Bremer Karsten H. G. Rätze Kai Sundmacher 《American Institute of Chemical Engineers》2017,63(1):23-31
Utilizing volatile renewable energy sources (e.g., solar, wind) for chemical production systems requires a deeper understanding of their dynamic operation modes. Taking the example of a methanation reactor in the context of power‐to‐gas applications, a dynamic optimization approach is used to identify control trajectories for a time optimal reactor start‐up avoiding distinct hot spot formation. For the optimization, we develop a dynamic, two‐dimensional model of a fixed‐bed tube reactor for carbon dioxide methanation which is based on the reaction scheme of the underlying exothermic Sabatier reaction mechanism. While controlling dynamic hot spot formation inside the catalyst bed, we prove the applicability of our methodology and investigate the feasibility of dynamic carbon dioxide methanation. © 2016 American Institute of Chemical Engineers AIChE J, 63: 23–31, 2017 相似文献
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Noboru Yoshikawa Guoqiang XieZiping Cao Dmitri V. Louzguine 《Journal of the European Ceramic Society》2012,32(2):419-424
An Fe3O4 powder compact was irradiated with a 2.45 GHz microwave single-mode applicator at the magnetic field maximum position. Selectively heated regions (hot spot region) having several hundred micrometers to millimeter scale were formed. They exhibited metallic color. The SEM/EDX observations showed no appreciable difference in the compositions between the hot spot regions and the matrix. However, micro-XRD revealed that the hot spot region had a larger fraction of FeO than the matrix did, although the major consisting phase was Fe3O4 with a little Fe2O3. TEM observations indicated that the observed hot spot regions comprise these oxide phases separated in nano-sized grains, which agrees with our previous report. The larger fraction of FeO phase and flat surface might be related with the metallic color of the hot spot region. Their formation mechanisms and phase constitution were discussed. 相似文献
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Jir̆í Hanika Karel Sporka Vlastimil Růz̆ic̆ka Richard Pis̆tĕka 《Chemical engineering science》1977,32(5):525-528
Transient axial temperature profiles were measured in a laboratory adiabatic trickle bed reactor. Attention was paid to hot spot formation within the bed. The appearance of the hot spot temperature is a result of evaporation of the liquid reaction mixture. The motion of the hot spot temperature is caused by axial heat transfer resembles propagation of flame during combustion. 相似文献
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King Hong Kwok 《Carbon》2003,41(12):2307-2316
CO2 Laser-induced chemical vapor deposition (LCVD) is being investigated as a possible technique of depositing uniform carbon coatings on moving fused quartz substrates. A CO2 laser is used to locally heat the substrate surface and create a hot spot where pyrolysis of hydrocarbon species occurs and subsequently deposits a layer of carbon film. The results indicate that uniform carbon film stripes can be deposited on moving fused quartz rods using pyrolytic LCVD only under certain deposition conditions, otherwise oscillation of the stripe width or substrate damage by laser radiation will occur. The transition region for oscillation, as well as the period of oscillation, is identified. Substrate damage can be induced by reducing the laser spot size, even when the substrate receives a lower irradiation intensity. Raman spectra of the carbon film stripes indicate that the film consists of disordered graphitic material. The ratio of the D-peak to the G-peak intensity found in the Raman spectrum is used to characterize the degree of disorder for the carbon film. The range of the Raman peak ratios is 0.795-0.935. 相似文献
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可渗透反应墙(PRB)技术是一种可靠、高效、低成本地修复受硝酸盐污染地下水的手段。文中介绍了PRB技术采用的各类碳源材料,分析对比了各类碳源材料的优缺点。液相碳源材料中,乙醇是最为理想的碳源材料,水解发酵污泥处理后获得的挥发性脂肪酸(VFAs)是未来的研究方向。固相碳源材料中,改性天然材料具有成本低廉、反硝化效果优异、释碳稳定的优点,以纤维素为碳源,可生物降解塑料为骨架的新型缓释碳源材料是未来应用的热点。 相似文献
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CO2的有效转化对于实现“双碳”目标具有重要意义。柱形颗粒比异形颗粒具有更优良的热导性和更小的颗粒表面积,因此,为获得更优异的床层性能,采用离散元方法(DEM)对异形颗粒混合堆积床内的CO2加氢反应体系进行颗粒尺度CFD模拟计算,探究不同堆积方式对床层多物理场分布、CO2转化率及CH4产率的影响。结果表明,催化剂内部存在扩散阻力,随着反应进行,颗粒内物质由分层分布渐变为均匀分布。随机混合床与常规床相比,随机混合床稳态前热点不易波动、稳态产率更高,而柱形床径向热场更均匀且热点更高。在四种规则混合床中,底部为4孔的两种催化剂床相较于底部为柱形的两种催化剂床,整体流场更均匀、高速区少、压降大、高温区占比大、稳态前热点不易波动;2层-底4孔催化剂床的稳态出口CO2转化率和CH4产率均最大;4层-底4孔催化剂床高温区占比较高,随着反应进行,高温区占比呈上升趋势,CO2转化率和CH4产率大幅下降。 相似文献