20 t/h锅炉锅筒爆裂事故分析

某锅炉投运半年，发生锅筒爆裂事故，详细分析发现，是由于锅炉严重缺水造成锅筒过热所致。找出原因后提出了改进措施及如何避免锅炉缺水的建议。     

卧式锅炉筒体鼓包原因分析及修复

分析了锅炉结垢引起锅筒鼓包的原因,依据规程制定了合理的锅筒挖补修理方案,修复了锅筒鼓包并检测合格,针对此类问题提出了安全预防措施,保证了锅炉安全正常使用.     

开工锅炉筒安装临时支架设计

1　概述我们所承建的兰州化学工业公司 2 0万ｔ乙烯改造工程中的两台ＤＧ45 4.2— 3型开工锅炉是向该装置提供开工及生产用过热蒸汽的重要设备。该锅炉是以重油为燃料的Ｄ型双锅筒自然循环水管锅炉 ,它是以散件形式出厂 ,在施工现场由施工单位组装成整体 ,施工难度大 ,技术要求高 ,是乙烯装置中的关键设备之一。锅炉由上、下两锅筒和布置在两个锅筒间的对流管束、燃烧室过热器等主要部分组成。锅炉由下锅筒支座和水冷壁支座支承在钢筋混凝土基础上。上锅筒通过对流管束支承在下锅筒上 ,详见图 1。图 1　ＤＧ4 5 4 2 -3型锅炉锅炉安装先将下…     

锅炉锅简底部鼓包、裂纹原因分析

通过化学成分、机械性能、金相、能谱等分析方法,对锅炉筒体产生鼓包及裂纹原因进行了分析。结果表明,锅炉底部沉积大量垢渣引起锅筒过热鼓包,而锅炉材质的内在缺陷对产生锅筒裂纹有直接影响。     

锅炉锅筒底部鼓包、裂纹原因分析

通过化学成分、机械性能、金相、能谱等分析方法,对锅炉筒体产生鼓包及裂纹原因进行了分析。结果表明,锅炉底部沉积大量垢渣引起锅筒过热鼓包,而锅炉材质的内在缺陷对产生锅筒裂纹有直接影响。     

DZG4-1.25-WⅡ型锅炉锅筒鼓包原因分析和对策

对一台DZG4-1.25-WⅡ锅炉锅筒鼓包的原因进行了分析,并提出相应的对策及该类型锅炉锅筒鼓包的预防措施。     

炉管胀接技术的研究与应用

炉管胀接技术广泛应用于中、低压锅炉以及换热设备的制造安装。胀接技术的原理主要是利用管口扩胀后管端的塑性变形、管板的弹性变形所产生的挤压应力使管端和管板啮合 ,来达到密封的效果。就锅炉炉管与锅筒的连接方式而言 ,有胀接和焊接两种。胀接连接与焊接连接相比 ,具有以下的优点 :①胀接产生的应力比焊接产生的残余应力的危险性要小得多。②在锅炉运行过程中 ,胀接对上下锅筒及整个炉管系统所产生的膨胀补偿作用比焊接要好得多。③胀接连接对锅炉的缺水事故敏感度高 ,能提高锅炉的安全性。④胀接连接时 ,炉管损坏易于更换、方便快捷。…     

废热锅炉服役后筒体环焊缝处的断裂失效研究

某氮肥公司合成氨系统的一台合成废热锅炉筒体环焊缝周围发生多处开裂。利用JB30B冲击试验机对废锅筒体环焊缝处材料的断裂韧性进行实验分析,同时结合断裂力学的基本理论对服役后废热锅炉筒体环焊缝处的开裂失效进行分析。结果表明：由于废锅焊缝区组织的晶界性能变差,使得材料的冲击韧性显著下降,抵抗裂纹扩展的能力降低,最终在机械应力、热应力及腐蚀环境的作用下,筒体环焊缝处发生多处晶间腐蚀开裂,从而导致筒体失效。     

电石尾气余热锅炉过热器爆管问题的解决

通过对过热器管片进行取样检测,结合过热器材质、水质不良、汽水分离装置不完善等方面分析了电石尾气余热锅炉过热器连续爆管的原因。结果表明,锅筒内部分离装置波形分离器失效,导致过热器管片蒸汽带水,过热器碱性腐蚀和积盐爆管。对波形分离器与锅筒连接处进行补焊,经过处理后的锅炉正常连续运行,蒸汽产量提高。     

锅炉锅筒管座角焊缝产生裂纹的原因分析及防治建议

我们在福建某电厂50MW的节能环保型机组的锅炉检验中,对锅筒管座进行表面无损检测,其中发现了大量的表面裂纹。对此我们对该台锅炉锅筒管座角焊缝进行了全面排查,并对产生裂纹的原因进行了分析,从而对锅筒制造、安装及运行等方面提出改进建议。     

Effect of Sulphur Dioxide and Sulphuric Acid on Steam Explosion of Aspenwood

Abstract

The use of steam explosion as a pretreatment for woody biomass prior to enzymatic hydrolysis has been proposed in the past. In this study the effect of SO2 impregnation (1.6% SO2 on dry wood input) and H2SO4 impregnation (0.58% H2SO4 on dry wood input) on the exploded substrates produced are compared with the case where no acid was added. Both acid catalysts substantially improve the survival of pentose sugars when treatments of equal severity are compared. H2SO4 however reduces the extent to which lignin may be extracted from the water washed exploded substrates with caustic.

The mode of action of the SO2 has been examined and, at the levels used in this work, approximately 50% of the input sulphur is shown to bind to the substrate forming, most likely, ligno-sulphonates.

The enzymic digestibilities of the acid impregnated steam exploded substrates are compared with those of the non-acid impregnated material and are shown to be more easily saccharified.     

良庄煤矿发展煤炭加工与综合利用的有效途径

良庄煤矿在发展煤炭加工与综合利用方面探索了一些有效途径 ,在洗选加工方面采用重介选煤工艺代替跳汰选 ,运行效果良好 ,利用浮选精煤制备水煤浆及燃煤锅炉改烧水煤浆、压滤煤泥发电及矸石制砖等方面均有显著的经济和环保效益     

Method for Studying the Interaction of Dispersed Water with Flame

This paper describes a laboratory method for studying flame suppression by a dispersed water cloud produced by an electrically exploded wire in a thin-wall cylindrical glass capsule filled with water. Experimental results are simulated numerically. __________ Translated from Fizika Goreniya i Vzryva, Vol. 42, No. 1, pp. 57–64, January–February, 2006.     

Enhanced ethanol production from enzymatically treated steam‐exploded rice straw using extractive fermentation

Alcohol fermentation of an enzymatic hydrolyzate of exploded rice straw was studied experimentally. Rice straw was treated under variable conditions, such as steam pressure and steaming time. The exploded rice straw was separated into water‐soluble material, methanol‐soluble lignin, Klason lignin, and a mixture of cellulose and a low molecular weight substance. The effects of steam explosion on the characteristics of the exploded rice straw were clarified from the point of view of the amounts of extractive components. Steam explosion was found to be effective for the delignification of rice straw and for increasing its susceptibility to enzyme hydrolysis and alcohol fermentation. The polysaccharides (cellulose and hemicellulose) in the rice straw treated at a steam pressure of 3.5 MPa with a steaming time of 2 min were hydrolyzed almost completely into monosaccharides, (ie glucose and xylose) by a mixture of Trichoderma viride cellulase (Meicelase) and Aspergillus aculeatus cellulase (Acucelase). The enzymatic hydrolyzate of exploded rice straw was converted into ethanol efficiently by Pichia stipitis and the ethanol yield from sugar was about 86%(w/w) of the theoretical value. The ethanol concentration in a membrane bioreactor coupled with a pervaporation system reached 50 gdm^?3 and was about five times higher than that in the culture broth. The energy efficiency (ratio of combustion energy of ethanol produced to energy for steam explosion) reached a maximum value at a pressure of 3.5 MPa for 2 min. © 2001 Society of Chemical Industry     

一起蒸汽管道爆炸事故分析

某化工厂蒸汽主管线上一对旋转补偿器在运行过程中突然发生爆炸,该管线从当地供热管网接入,输送蒸汽为过热蒸汽。蒸汽管道设计压力为1.1MPa,设计温度为250℃,正常运行参数为0.8MPa、200℃。通过对爆炸现场的勘察和对当地供热管网系统的综合分析,认为水击是造成这次爆炸事故的直接原因。     

Chemical Pulping of Steam‐Exploded Mixed Hardwood Chips

Abstract

We determined the pulping yields for steam‐exploded and untreated mixed hardwood chips for kraft pulping processes with and without anthraquinone and/or polysulphide. The pulp yield from steam‐exploded chips was 1–3% lower than from untreated chips under similar conditions. The benefit of kraft pulping with anthraquinone and/or polysulphide was found to be more pronounced for the exploded chips than for the untreated chips.     

新型钢丝网骨架增强塑料复合管的有限元分析

应用ANSYS软件对一种新型管材－钢丝网骨架增强塑料复合管进行了强度计算分析，给出了复合管压力与弹性变形的关系式。用一具体的算例得到了确定该类型复合管的爆破压力及弹性压力范围的方法。通过相同爆破压力下纯塑料管的最薄厚度的确定，以及与复合管相同厚度的塑料管的最大爆破压力的计算，说明了这种新型管材的优点。并通过试验验证了计算结果的正确性。     

基于SolidWorks爆炸图的产品说明书制作

本文主要介绍利用SolidWorks的爆炸图及工程图制作产品说明书,主要阐述了SolidWorks的爆炸图主要功能以及其工程图的一些基本功能。事实证明爆炸图对于说明书的制作有非常重要的作用。     

连续式蒸汽爆破对PP/棉杆纤维复合材料力学性能的影响

以连续式蒸汽爆破预处理的棉杆作为增强纤维,通过模压成型制得聚丙烯(PP)/棉杆纤维复合材料.研究了蒸汽爆破条件中纤维含水量及爆破次数对复合材料力学性能的影响.结果表明,该预处理使复合材料力学性得以改善.当纤维含水量为40%、爆破次数两次时,获得的复合材料综合力学性能最佳.