479 / 2018-12-31 04:11:11

液态排渣锅炉燃用高碱煤的适用性探究

高碱煤，液态排渣锅炉，结渣，适用性

全体主题 > 燃料利用与化学循环技术

新疆准东地区高碱煤资源丰富，煤种挥发分高，燃尽性好，低硫，低成本，可作为优质的动力用煤。但高碱煤在实际运行中表现出使锅炉受热面严重结渣的特性。结渣问题严重制约着高碱煤的安全燃用。
液态排渣锅炉是为了适应难着火而又容易结渣煤的燃烧而发展起来的一种炉型。液态排渣炉的设计思想是在排渣室内部保持足够高的温度，使50%左右的灰渣熔化，以液态渣的形式从炉膛下部排渣口排出，经过渣井落入粒化水箱。另50%左右的灰分变成飞灰随烟气进入对流受热面，大大减少进入对流受热面的烟气中的飞灰浓度，降低对流受热面结焦的风险。液态排渣锅炉相比固态排渣锅炉的优势在于它克服了固态排渣锅炉燃用易结渣煤种时炉膛水冷壁、对流受热面严重结渣和高温腐蚀等缺点，特别适宜烧灰熔点较低的易结渣煤。
本文通过将华能北京热电有点责任公司实际运行液态排渣锅炉的流渣特性与高碱煤的熔渣结焦特性进行对比与分析，探究液态排渣炉燃用高碱煤的适用性，并对在电厂液态排渣锅炉进行高碱煤的掺烧（纯烧）试验做出展望。
The region of Zhundong in Xinjiang is abundant in high alkalis coal, which is excellent coal for power plants due to its high volatile content, well burn out property, low sulfur content and low cost. The problem that the high alkalis can lead to severe fouling and slagging restricts the popularization and application of high alkalis coal.
Liquid slag boiler is used to adapt the combustion of the coal which is difficult firing and easy slagging. The temperature is very high in slag discharger chamber of the liquid slag boiler. Half of the slag is in molten state discharging from the slag discharge opening at the bottom of the chamber. The other half of the ash goes through the heating surface with the flow of flue gas. Low fly ash concentration makes it less possible slagging on the heating surface. Liquid slag boiler has an advantage over solid slag boiler which is about severe fouling and slagging on the heating surface and high temperature corrosion. Liquid slag boiler is suitable for coal with low-ash-fusion temperature and easy slagging in combustion.
In this study, the applicability of high alkalis coal combustion in liquid slag boiler is studied due to slag character in actual operational condition in Huneng Beijing Co-generation Co.,Ltd. Power Plant and slag character of high alkalis coal. There is a prospect for high alkalis coal co-firing test in liquid slag boiler in this thesis as well.