共查询到18条相似文献,搜索用时 93 毫秒
1.
2.
3.
基于某热电厂实际情况,分析该厂煤粉锅炉水冷壁高温腐蚀的机理、高温腐蚀的影响因素并探讨抑制措施。 相似文献
4.
5.
6.
由于生活垃圾成分复杂,生活垃圾焚烧发电锅炉的水冷壁的高温腐蚀问题也更为复杂,腐蚀会导致管壁过薄,对锅炉运行产生严重的安全隐患。文中通过对某台垃圾焚烧发电锅炉的腐蚀情况进行研究,并分析该台垃圾焚烧发电锅炉水冷壁腐蚀产物的元素含量,结合垃圾成分,运行中焚烧炉出口O_2/CO的含量,推断该锅炉水冷壁的腐蚀主要为高温Cl腐蚀。并针对水冷壁的腐蚀,采用涂覆Cr-Ni防腐材料对该锅炉第一烟道水冷壁进行了表面防腐,经半年的运行观察,该防腐涂层的防腐效果较好。 相似文献
7.
燃煤锅炉水冷壁烟侧高温腐蚀的机理及影响因素 总被引:9,自引:0,他引:9
随着对环保要求的日益提高以及煤粉锅炉向大容量高参数发展,电厂燃煤锅炉水冷壁高温腐蚀现象的发生日趋频繁,有的甚至已经影响到锅炉运行的安全性与经济性。作者系统地论述了水冷壁高温腐蚀的类型以及形成机理,分析了影响高温腐蚀的各种因素,为解决煤粉煤炉水冷壁高温腐蚀提供了一定的理论依据。 相似文献
8.
9.
因高温硫腐蚀和结渣导致锅炉水冷壁管减薄爆管的问题日益突出,根据电厂实际情况,对水冷壁高温腐蚀和结渣的原因进行了分析,并通过冷热态试验进行了验证,最后提出了具体对策,如减小炉内切圆直径、改善壁面还原性气氛等措施。 相似文献
10.
《锅炉技术》2021,52(4)
切圆燃烧锅炉不同配风方式对锅炉热效率和NO_x排放浓度的研究文献很多,但其对炉内整个燃烧区域高温腐蚀的影响特性的报道较少。以某660 MW超临界机组锅炉为研究对象,通过现场测试,研究了不同配风方式对NO_x排放浓度和炉膛水冷壁高温腐蚀的影响特性,并给予了炉内水冷壁高温腐蚀运行防控方面的指导。额定负荷运行工况下,建议AA托底风风门挡板开大,有利于控制冷渣斗区域水冷壁的高温腐蚀;开大周界风门挡板以及关小紧凑燃尽风(CCOFA)和分离燃尽风(SOFA)风门挡板,将缓解主燃烧器与燃尽风之间区域水冷壁、主燃烧器区域水冷壁和冷渣斗区域水冷壁的高温腐蚀,这将为同类型机组运行提供指导和借鉴。 相似文献
11.
大型锅炉水冷壁高温腐蚀探讨 总被引:8,自引:0,他引:8
从理论和实际出发 ,阐述了水冷壁发生高温腐蚀的类型 ,大型贫煤锅炉水冷壁发生高温腐蚀的原因 ,四角切圆燃烧方式防止高温腐蚀的措施。针对石洞口电厂锅炉改造 ,提出防止高温腐蚀的具体措施。 相似文献
12.
Stress corrosion cracking (SCC) is an important degradation mechanism to be considered for safety assessment of nuclear piping components made of austenitic steels, especially in the heat-affected zones. Damage due to SCC occurs in a susceptible material, in a corrosive environment, in the presence of high temperature and high applied/residual stresses. The operating conditions and the environmental conditions show variations during the lifetime of the power plant. Also, there will be variations in micro-structural properties of the material of piping components. These variations should be taken into account while assessing the safety of the piping component against SCC. This can be accomplished by treating the relevant variables as random or fuzzy depending upon the source and type of uncertainty. In this paper, an attempt has been made to compute the fuzzy failure probabilities of a piping component against SCC with time, using an approach combining the vertex method with the Monte Carlo simulation technique. The initiation and propagation stages of stress corrosion cracks are modelled using a modified PRAISE approach. The degree of sensitisation, material fracture toughness, yield strength, ultimate strength and applied stress are considered as random variables, while operating temperature and oxygen concentration are considered as fuzzy variables. The R6 procedure is used in the computation of the fuzzy failure probabilities. The usefulness of the approach is demonstrated through an example problem. 相似文献
13.
针对某电厂600 MW墙式对冲燃烧锅炉在低氮燃烧改造后存在严重的水冷壁高温腐蚀问题,采取LYCTWA型贴壁风系统对其进行了高温腐蚀治理改造。通过全炉膛数值模拟与现场试验相结合的方法,研究了侧墙壁面区域的烟气成分分布以及不同的贴壁风布置方案对炉内燃烧及高温硫腐蚀的影响。结果表明:模拟结果与电厂实际腐蚀区域相吻合,腐蚀区域主要集中在第2层主燃烧器至燃尽风间的侧墙区域。加装了贴壁风系统后,数值模拟和试验结果均显示侧墙还原性气体体积分数大幅降低,水冷壁贴壁气氛得到显著改善。 相似文献
14.
15.
16.
17.
The laminar unsteady natural convection in a cubic cavity is comprehensively studied here using a high accuracy temporal-spatial pseudospectral method. In this study, the cavity is filled with air and one of its sidewalls is submitted to sinusoidally varying temperature, while constant lower temperature is imposed on the opposing sidewall and other sidewalls are adiabatic. Computations are performed to explore the effects of several influential factors on the fluid flow patterns and heat transfer performances within the cavity, including Rayleigh number and the amplitude and period of pulsating sidewall temperature. Numerical results reveal that the heat transfer enhancement is complexly determined by the above influential factors, and the heat transfer resonance is observed in the case of a large Rayleigh number and amplitude of pulsating sidewall temperature. The three-dimensional effects on fluid flow patterns and heat transfer are discussed. Finally, the backward heat transfer is quantitatively studied. 相似文献