抽提蒸馏塔倒塌事故的原因分析及塔体修复

对抽提蒸馏塔在停车蒸塔过程中,塔内发生自燃,引发塔体倒塌事故的原因进行了分析,为防止类似事故的发生,提出了必要的防范措施,着重介绍了塔体的更换方法。     

芳烃抽提溶剂劣化原因分析及对策

某炼化公司芳烃抽提装置所用环丁砜溶剂在运行中出现了劣化问题,主要体现在溶剂系统色泽变差,杂质变多,pH值下降,对溶剂抽提效果和设备腐蚀等产生影响。从芳烃抽提生产实际出发,通过对环丁砜抽提操作的温度、真空度、水、添加剂等因素的分析,讨论了环丁砜溶剂热分解、氧化分解、水解和添加剂的影响因素,并针对相应影响因素提出了环丁砜溶剂优化的对策。     

芳烃抽提装置非芳烃蒸馏塔顶后冷器泄漏原因分析

芳烃抽提装置非芳烃蒸馏塔顶后冷器E115管束发生泄漏.通过对管束腐蚀形貌、垢样组成、装置运行工况和装置腐蚀现状等因素进行分析,发现环丁砜溶剂降解和氯离子累积的叠加作用是管束频繁发生腐蚀泄漏的原因.采取材质升级、控制工艺操作和定期测厚等措施,消除了设备隐患,为装置长周期可靠运行提供了保障.     

常压炉辐射室炉管脱挂倒塌原因分析

常减压装置常压加热炉因停电停汽,辐射室炉管超温脱挂和倒塌,分析其原因一是停 电同时停蒸汽,炉管不能注汽超温线膨胀量超过预留允许膨胀量,二是设计缺陷。     

钻井泵阀盖金属密封失效原因与维修方法

钻井泵在使用中经常出现高压泥浆冲蚀或刺坏阀盖喷射泄漏事故,造成钻井泵停机维修.分析了钻井泵阀盖的工作原理,找出其失效原因并采取了相应措施,以改善阀盖的工作状况,提高钻井泵的使用性能.     

苯甲酸蒸馏塔内件腐蚀失效分析和防护对策

用化学方法、金相显微镜和扫描电镜等对失效后的苯甲酸蒸馏塔塔内件(支撑圈和降液板)进行了分析,结果表明,支撑圈的腐蚀失效模式为严重的P、Si偏析所引起的非敏化态晶间腐蚀造成的晶粒脱落直至穿孔,并伴有晶间和穿晶混合型应力腐蚀开裂。折流板的失效模式是晶间型的应力腐蚀开裂,其拉应力是由温差带来的。最后提出了相应的防护措施。     

顺丁清理胶自燃原因分析

对不同样态的顺丁橡胶进行自然阳光曝晒、催化剂反应,考察橡胶自燃的可能性;并采用热失重技术和X射线—荧光光谱技术,分析橡胶中各常见元素的含量。试验结果表明,顺丁橡胶本身难以自燃,橡胶中含有的活性铝粉和清理过程中产生的金属氧化物是着火的主要原因。     

板式换热器失效原因分析及维修方法

介绍了板式换热器的主要零部件设计特点以及在化工装置使用过程中的注意事项．分析了板式换热器失效的原因，提出了板式换热器的检维修方法和要求，并在板式换热器长周期运行方面进行了探讨。     

承包商事故多发的原因分析和预防措施

对承包商事故多发的原因进行了分析，提出了减少事故发生的具体措施：严把承包商入场关，建立安全生产责任制，规范开展承包商安全教育，强化危害识别和风险评估工作，加强现场的监督和建立承包商安全考核制度。     

计算机硬件常用维修方法和技巧

计算机设备使用日久、使用不当或意外受损，出现故障是难免的，作为维护人员，要想快速准确的排除故障，除掌握必要的基本理论外，还需具备一定的检修方法和故障处理技巧。本文从故障分类入手，分析了计算机发生故障的原因，介绍了常用的维修方法和技巧。     

常压塔人字架整体吊装方法

人字架吊装法是一种简单、经济、可靠的吊装方法适用于中型塔类设备的整体吊装，特别是在起重能力不足时，其经济性和安全性尤为明显。通过某厂100×104t／a常压蒸馏装置常压塔的吊装，介绍了人字架吊装的特点、机具设置、主要受力分析和吊装工艺。     

萃取精馏与变压精馏分离甲醇-乙腈共沸物的研究

In the present work, a comparative study of the extractive distillation and pressure swing distillation for methanol-acetonitrile azeotropic separation is performed for the first time. Different separation alternatives, including the conventional extractive distillation, the extractive distillation with vapor or liquid side-stream, the pressure-swing distillation with or without full heat integration, and the heat-pump assisted pressure-swing distillation are rigorously simulated and optimized based on the minimum total annual cost (TAC) via the sequential iterative strategy. The results show that TAC and CO2 emission of the new extractive distillation with vapor side-stream (Vapor-SED) are similar to that of the extractive distillation with liquid side-stream (Liquid-SED). Furthermore, the Vapor-SED and Liquid-SED gives 30.01% and 30.56% reduction in TAC and 23.32% and 23.49% reduction in CO2 emission, respectively, over the most competitive fully heat-integrated PSD configuration. Hence, extractive distillation with vapor or liquid side-stream appears to be better option economically and environmentally for separation of methanol and acetonitrile.     

乙二胺与N-乙基乙二胺萃取精馏溶剂的选择

常压下,测定了乙二胺-N-乙基乙二胺、乙二胺-乙二醇、N-乙基乙二胺-乙二醇二组分物系的汽液平衡数据,由实验数据关联了Wilson模型参数。选取β-苯乙醇和乙二醇作为萃取剂,在萃取剂存在条件下进行了物系的汽液平衡计算和实验验证。实验和计算结果表明,乙二醇是乙二胺和N-乙基乙二胺萃取精馏的有效萃取剂,β-苯乙醇不是有效的萃取剂。采用乙二醇作为萃取剂时,N-乙基乙二胺与乙二胺的相对挥发度增大,原难挥发的组分N-乙基乙二胺转变为易挥发组分。     

丁二烯抽提技术的比较和分析

比较和分析了目前最通用的3种丁二烯抽提工艺(BASF公司的N-甲基吡咯烷酮抽提工艺、Zeon等公司的二甲基甲酰胺抽提工艺和Shell等化学公司的乙腈抽提工艺)的溶剂物性参数、组织工艺流程的技术思想、整体技术经济水平,讨论了溶剂的各种物性参数的作用,重新评价了这3种丁二烯抽提工艺的环保和安全水平,分析了流程集成技术的应用情况。提出了今后我国在新建丁二烯抽提生产装置时选择抽提工艺的有关建议。     

萃取精馏分离甲醇-碳酸二甲酯共沸物的研究

基于甲醇与碳酸二甲酯的共沸特性,利用Aspen Plus化工模拟软件对其分离过程进行模拟和分析,采用Wilson模型对实验数据进行关联。考察了共沸体系在不同萃取剂下的相对挥发度。选择乙二醇作为萃取剂,对双塔萃取、隔壁塔萃取以及单塔萃取方式进行了比较,发现采用隔壁塔萃取方式时,甲醇和碳酸二甲酯的纯度更高,且萃取剂的回收率约为100%;由于副塔没有再沸器,在能量利用方面也有绝对的优势。     

萃取精馏分离甲基环己烷和甲苯工艺过程的模拟

利用Aspen Plus流程模拟软件,采用双塔流程,以苯酚为萃取剂,对萃取精馏分离甲基环己烷(MC)和甲苯(MB)的过程进行模拟计算,并用实验验证。考察了萃取精馏塔的萃取剂进料位置、原料进料位置、萃取剂与原料的摩尔比(溶剂比)和回流比等因素对分离效果的影响。在满足MC产品的纯度和收率均达到99%的条件下,模拟优化的结果为:理论塔板数为24块,原料在第17块板进料,萃取剂在第5块板进料,溶剂比3.08,回流比5。模拟结果与实验数据吻合较好,说明采用的模拟方法适用于MC和MB混合物萃取精馏过程的模拟。     

Effect of Solvents for the Production of Cyclopentane by Extractive Distillation

Abstract

In view of the rapid phasing out of fluorocarbons due to their adverse ozone-depleting potential, alternative environment-friendly chemicals are being explored for blowing polyurethane, the key insulation material in refrigeration industries. Cyclopentane with required physical and thermal conductivity properties has emerged as the most appropriate alternative as it can be acquired from light petroleum hydrocarbons, which are abundant. Light naphtha is a mixture of several closely boiling hydrocarbons and hence even a narrow fractional distillation may not enrich cyclopentane for required purity and instead it results only in an azeotropic mixture. This article describes the work carried out in obtaining commercially pure cyclopentane from light naphtha through an extraction-distillation combined operation which is commonly termed as “extractive distillation.” The solvent type and key operating parameters, namely, feed naphtha cut range (heart cut), solvent/feed ratio were studied and the results obtained were further correlated with simulated model prediction.     

Effect of Solvents for the Production of Cyclopentane by Extractive Distillation

In view of the rapid phasing out of fluorocarbons due to their adverse ozone-depleting potential, alternative environment-friendly chemicals are being explored for blowing polyurethane, the key insulation material in refrigeration industries. Cyclopentane with required physical and thermal conductivity properties has emerged as the most appropriate alternative as it can be acquired from light petroleum hydrocarbons, which are abundant. Light naphtha is a mixture of several closely boiling hydrocarbons and hence even a narrow fractional distillation may not enrich cyclopentane for required purity and instead it results only in an azeotropic mixture. This article describes the work carried out in obtaining commercially pure cyclopentane from light naphtha through an extraction-distillation combined operation which is commonly termed as “extractive distillation.” The solvent type and key operating parameters, namely, feed naphtha cut range (heart cut), solvent/feed ratio were studied and the results obtained were further correlated with simulated model prediction.     

NFM-COS复合溶剂萃取精馏分离苯

采用N -甲酰吗啉 (NFM )添加一种助溶剂 (COS)构成复合溶剂作萃取精馏溶剂 ,从裂解加氢汽油苯馏分中回收高纯苯。研究了助溶剂含量、溶剂比等因素对萃取精馏效果的影响 ,适宜的助溶剂质量分数为 5 %～ 2 0 % ,溶剂比为 4 5～ 6 0。采用复合溶剂 ,苯产品收率达到 99 8% ,溶剂回收温度降至 190℃以下 ,与NFM单溶剂萃取精馏工艺相比 ,具有产品质量好、苯收率高、操作苛刻度低的优点