一台立式锅炉爆炸事故分析

分析厂立式横水管锅炉炉胆的稳定性，讨论了高温下炉胆失稳的可能性。分析了锅炉爆炸事故的产生原因，提出了防止过热情况下立式锅炉炉胆失稳的措施。     

立式锅炉炉胆试压装置

小型立式锅炉炉胆尺寸一般较小,制造厂在制成锅炉本体后,对其进行水压试验时,炉胆与管子之间的焊接接头有无渗漏不太容易检查。尤其是即使发现有渗漏,返修也比较困难。针对这种情况,我厂专门设计了一种简易的炉胆水压试验装置(见图),对本厂生产的LSG0.2—0.4双层炉排锅炉的炉胆部件预先进行水压试验,等试压合格后,再与外锅筒焊接成为     

立式燃油锅炉的创意设计

介绍了一种突破水管锅炉与火管锅炉界限的新型立式锅壳、炉胆、水管组合的燃油锅炉,旨在使立式燃油锅炉在容量、参数与性能上有所突破。     

立式锅炉内胆失稳模拟试验及其意义

立式锅炉凶缺水造成炉胆超温,在外压作用下失稳,从而引起锅炉爆炸。试验利用两个夹套圆简试件来模拟立式锅炉缺水超温内胆失稳过程,测定试件内筒失稳时的临界压力并与理论计算值进行比较,讨论影响失稳临界压力和波数的因素,并且提出相应的设计、制造要求。     

立式锅炉失效原因分析

在事故调查分析的基础上,总结了立式锅炉的失效原因。分析了横水管对炉胆稳定性的影响,定量分析了不同工况下炉胆失稳的条件,提出了相应解决措施。     

炉胆氧腐蚀原因分析及防护措施

就检验中发现的锅炉炉胆氧腐蚀情况进行了合理分析,详细介绍了炉胆氧腐蚀的机理和各种影响因素,并为防止炉胆氧腐蚀提出了相应方法,为解决工业生产中普遍存在的锅炉炉胆氧腐蚀问题提供了参考.     

热管技术在立式锅炉上的应用

本文着重论述的是近几年生产的一种将热管布置在小型锅炉的高温侧,即作为炉内传热元件的立式锅炉的有关问题: 一、传统的正、反烧立式水(火)管锅炉不完善的方法。 二、热管立式锅炉的传热机理。 三、热管立式炉与水管立式炉的比较。 四、常压热管炉在上海通过产品鉴定。 五、热管锅炉技术的新发展。 六、热管锅炉推广前景与尚待解决的问题。     

锥形炉胆制造工艺初探

锥形炉胆制造工艺初探戴国栋（福州锅炉厂）锥形炉胆是全自动燃油锅炉中连接前管板与波形炉胆、波形炉胆与温烟箱前管板的重要受压元件（参见图１）。采用锥形炉胆的目的在于缩小锅炉的总体制造尺寸，减小产品的体积，却能产生比一般锅炉多得多的热能。以下仅对我厂新开发...     

燃油锅炉讲座（续六）

燃油锅炉的系统及要求6 1　油炉的燃烧室燃油锅炉的燃烧室 (炉膛 )应满足的要求 ,已在《能源工程》2 0 0 0年第 5期 (Ｐ61～Ｐ62 )讨论过了 ,这里再具体介绍几种燃油锅炉的燃烧室。6 1 1　立式锅壳无管锅炉———Ｆｕｌｔｏｎ锅炉美国富尔顿锅炉的特点是一种没有水管和烟管的锅炉 ,其受热面设计为内外套筒结构 ,内筒(炉胆 )为辐射受热面 ,带肋片的外筒为对流受热面 ,见图 1所示。1 鼓风机　 2 水位表　 3 水空间　 4 保温层5 肋片　 6 锅炉外壳　 7 蒸汽出口　 8 蒸汽空间9 燃烧器　 10 火焰滞留器　 11 进水口12 排污口　 13 烟气…     

炉胆顶与“S”下脚圈成组冲压模具的设计

炉胆顶(图1)与“S”下脚圈(图2)是立式锅炉的重要零件。材料为20g。其特点是板料较厚,直径较大,内径偏差、椭圆度、平面度要求较高。过去制造多采用分别下料加热拉延的加工方法供坯。这不仅费工费料,而且两件在与炉胆组装时的对接质量也难以保证。为此,我们厂设计了一付成组冲压模具,把炉胆顶与“S”下脚圈归并成组(图3),一次加热冲压成形,然后气割分开。实践证明,技术经济效果良好。     

1000MW塔式直流锅炉炉膛水冷壁管壁温度和热负荷分布的试验研究

对2台1 000MW超超临界压力塔式直流锅炉炉膛水冷壁管壁温度和热负荷分布进行了测量和计算,并对不同负荷工况、不同磨煤机投运方式下的热负荷和管壁温度分布规律以及炉膛上部垂直水冷壁的热负荷分布进行了分析.结果表明:1 000MW塔式直流锅炉炉膛热负荷的分布规律与其他四角切圆燃烧锅炉炉膛热负荷的分布规律基本一致.由于在最上层的燃烧器上方布置了燃尽风,对炉内烟气的扰动加强,导致沿管长方向的热负荷在54m标高处波动较大;在燃尽风喷嘴中心线以上,因受到燃尽风进入炉膛的影响,水冷壁热负荷大幅度下降.为了避免炉膛大比热区传热恶化,可以将处于拟临界点附近的水冷壁布置在低热负荷区域.     

国产UP直流炉水冷壁改造方案分析

针对姚孟电厂300MW直流锅炉改造方案进行了水动力分析,对比了改造前后锅炉水冷壁的负流量响应特性和正流量响应特性,指出该炉垂直管圈炉膛水冷壁水动力特性不佳,低负荷运行造成水冷壁超温及管间流体和金属温差大爆管的主要原因是高质量流速设计及其产生的负流量响应特性,给类似锅炉改造提供了借鉴经验。     

1000MW超超临界锅炉水冷壁壁温计算

采用分区计算简化大容量高参数超超临界锅炉炉内辐射、对流传热模型,研究炉膛水冷壁热负荷及壁温的空间分布情况,并与试验数据进行了对比,计算结果与试验值之间的偏差较小,最大为5.72%.该模型与算法可给出不同锅炉负荷条件下,水冷壁壁面热负荷与壁温沿炉膛宽度方向的分布规律.结果表明,水冷壁热负荷与壁温均呈现出中间高两端低的弧形分布.四角切圆燃烧锅炉火焰位置对炉内传热有很大影响.模拟计算可为超超临界锅炉的运行提供参考,预测了在材料允许温度范围内,火焰中心偏斜最大不超过2 m.     

Coupled Heat Transfer Simulation of the Spiral Water Wall in a Double Reheat Ultra-supercritical Boiler

This paper presented a coupled heat transfer model combining the combustion in the furnace and the ultra-supercritical(USC) heat transfer in the water wall tubes. The thermal analysis of the spiral water wall in a 1000 MW double reheat USC boiler was conducted by the coupled heat transfer simulations. The simulation results show that there are two peak heat flux regions on each wall of spiral water wall, where the primary combustion zone and burnt-out zone locate respectively. In the full load condition, the maximal heat flux of the primary combustion zone is close to 500 kW/m~2, which is higher than that in the conventional single reheat USC boilers. The heat flux along the furnace width presents a parabolic shape that the values in the furnace center are much higher than that in the corner regions. The distribution of water wall temperature has a perfect accordance with the heat flux distribution of the parabolic shape curves, which can illustrate the distribution of water wall temperature is mainly determined by heat flux on the water wall. The maximal water wall temperature occurs at the middle width of furnace wall and approaches 530°C, which can be allowed by the metal material of water wall tube 12Cr1MoVG. In the primary combustion zone, the wall temperatures in half load are almost close to the values in 75% load condition, caused by the heat transfer deterioration of the subcritical pressure fluid under the high heat flux condition. The simulation results in this study are beneficial to the better design and operational optimization for the double reheat USC boilers.     

700 MW四角切圆燃烧锅炉降低水冷壁高温腐蚀配风改造应用研究

为防治四角切圆燃煤锅炉炉膛水冷壁高温腐蚀,在某电厂2台700 MW机组锅炉上进行了燃烧配风优化改造,并进行了燃烧调整试验.结果表明:燃烧配风优化改造后,锅炉水冷壁贴壁气氛显著改善,炉膛水冷壁高温腐蚀得到有效防治,锅炉运行安全性和经济性显著提高,为四角切圆燃烧电站锅炉防治水冷壁高温腐蚀提供了积极的示范作用.     

Solved and Thermal-Hydraulic Problems Systems: Learning from Accidents Unsolved in Boiler

This article begins with a brief review of the similarity law of conventional fossil fuel-fired boilers. The concept is based on the fact that the heat release due to combustion in the furnace is restricted by the furnace volume but the heat absorption is restricted by the heat transfer surface area. This means that a small-capacity boiler has relatively high specific furnace heat release rate, about 10 MW/m 3 , and on the contrary, a large-capacity boiler has a lower value. The surface heat flux limit is dominated mainly by the critical heat flux (CHF) inside the water wall tubes of the boiler furnace. This heat flux limit is almost the same order, independent of the capacity of the boiler. For the safety of water walls, it is essential to retain a good amount of water circulation, i.e., the circulation ratio and velocity of the water must be high enough above the respective critical values. This principle is common knowledge in boiler designer, but the actual situation is not the case. Newly designed boilers often suffer from similar accidents, especially burnout due to water circulation problems. This article demonstrates recent accidents encountered in practical boilers, and raises rather classical but important problems related to two-phase flow and heat transfer.     

300MW循环流化床锅炉屏式受热面传热系数计算及其变化规律

根据300MW循环流化床（CFB）锅炉现场测试数据并结合以往CFB锅炉传热系数的研究成果,建立了屏式受热面烟气侧的传热模型,包括辐射传热模型和对流传热半经验公式．利用该模型对某300MWCFB锅炉在94％锅炉最大连续蒸发量（BMCR）工况下炉膛内屏式受热面的传热系数进行了计算,分析了屏式受热面管间节距、炉膛温度、工质温度、壁面黑度及烟气速度等因素对传热系数的影响．结果表明：烟气速度、炉膛温度和壁面黑度对传热系数的影响较大,所建立的传热模型能够合理地反映主要因素对CFB锅炉屏式受热面传热的影响．     

基于表面温度控制的卫燃带设计方法

提出了基于卫燃带向火面表面温度计算及控制的卫燃带设计方法,并根据炉内火焰与水冷壁管及卫燃带间的集总参数换热模型及卫燃带向火面至水冷壁管内工质各个环节的传热模型,建立了将卫燃带向火侧的表面温度与锅炉负荷、卫燃带材料导热系数、卫燃带敷设厚度与面积关联的代数模型,并运用该模型对1台燃用阳沁无烟煤的1025 t/h四角切圆燃烧煤粉锅炉的卫燃带进行了传热计算.结果表明:锅炉负荷对卫燃带的表面温度影响最大,并且成近似线性关系;卫燃带厚度对表面温度的影响显现出对数函数的特性;卫燃带表面温度随材料导热系数的下降快速升高;卫燃带表面温度随面积的增加而缓慢增加;计算结果与国内1025 t/h同类型煤粉锅炉卫燃带的实际应用情况吻合.     

Heat flux distribution on circulating fluidized bed boiler water wall

The future of circulating fluidized bed (CFB) combustion technology is in raising the steam parameters to supercritical levels. Understanding the heat flux distribution on the water wall is one of the most important issues in the design and operation of supercritical pressure CFB boilers. In the present paper, the finite element analysis (FEA) method is adopted to predict the heat transfer coefficient as well as the heat flux of the membrane wall and the results are validated by direct measurement of the temperature around the tube. Studies on the horizontal heat flux distribution were conducted in three CFB boilers with different furnace size, tube dimension and water temperature. The results are useful in supercritical pressure CFB boiler design.     

降低循环流化床锅炉结渣风险的准东煤配煤掺烧研究

针对循环流化床锅炉燃用准东煤带来的受热面结渣和沾污问题,从降低入炉煤碱金属着手,采用准东五彩湾煤掺烧不同比例的煤矸石、低钠煤、沙漠黄沙,探究不同掺烧物料及比例对锅炉受热面结渣和沾污的影响。研究结果表明:掺烧25%煤矸石时,炉内受热面沾污、结渣严重,且存在频发的爆管现象;掺烧38%艾维尔沟低钠煤时,各级受热面均比较干净,没有明显的结渣沾污现象,但锅炉运行成本显著增加;掺烧5%古尔班通特沙漠黄沙时,仅在一级蒸发管高温烟区出现了类似于沙子的大焦块,其余受热面均比较光滑、干净,没有结渣和沾污现象。