The evaluation of waste tyre pulverised fuel for NOx reduction by reburning
The evaluation of waste tyre pulverised fuel for NOx reduction by reburning
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DOI：
10.1016/j.fuel.2008.03.023
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发表时间：
2008-10
期刊：
影响因子：
7.4
通讯作者：
W. Nimmo;Surjit Singh;B. M. Gibbs;Paul T. Williams
中科院分区：
文献类型：
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作者：
W. Nimmo;Surjit Singh;B. M. Gibbs;Paul T. Williams
燃煤发电在未来将继续发挥重要作用，然而，这必须使用比我们目前使用的更清洁的技术来实现。英国每年产生的废轮胎有40万吨，相当于3000万个轮胎，而在整个欧盟，每年有超过250万吨的轮胎被废弃。最近的欧盟废物填埋指令（1999年）规定了到2006年禁止在填埋场使用整胎和碎胎的最后期限。因此，迫切需要找到一个大规模的轮胎处理路线。本文描述了轮胎橡胶粉燃料在nox再燃烧过程中的一种新用途，这种新用途可能在电站锅炉中得到应用。这种处理方法可以代表一种将废物处理、能源回收和污染控制在一个过程中结合起来的方法。对微细化轮胎燃烧进行了初步研究，以确定通过再燃烧减少nox的合适尺寸范围。试验是在功率约为80kW的下燃粉状燃料燃烧器（PFC）中进行的。当颗粒尺寸小于250μm时，实现了优异的燃烧特性，即燃尽。在再燃试验中，使用南非煤作为主要燃料，轮胎通过一个单独的进料系统进行气动进料。研究了再燃区化学计量学和再燃燃料分数。此外，在富燃料再燃化学计量中，仔细监测灰分的碳含量对燃尽的任何影响。将使用轮胎减少的nox与用煤再燃烧进行比较。轮胎的再燃燃料进给率是燃煤燃料进给率的一半，可减少高达80%的nox。这些结果已经在文献中关于烟煤、褐煤、天然气和生物质再燃烧nox的其他研究的背景下进行了评估。
The combustion of coal for power generation will continue to play a major role in the future, however, this must be achieved using cleaner technologies than we use at present. Scrap tyre arisings in the UK are 400,000 tonnes per year amounting to 30 million tyres and in the EU as a whole, more than 2.5 million tonnes of tyres per year are scrapped. The recent EC Waste Landfill Directive (1999) sets a deadline for the banning of whole and shredded tyres from landfill sites by 2006. Consequently, there is an urgent need to find a mass disposal route for tyres. We describe, in this paper, a novel use for tyre rubber pulverised fuel in a NOxreburning process which may have an application in power station boilers. This method of disposal could represent a way of combining waste disposal, energy recovery and pollution control within one process. A preliminary study of micronised tyre combustion was undertaken to identify the suitable size ranges for application in NOxreduction by reburning. Tests were performed in a down-fired, pulverised fuel combustor (PFC) operating at about 80kW. Superior combustion characteristics, i.e. burnout were achieved with particle sizes less than 250μm. A South African coal was used as the primary fuel in the reburn tests and the tyre was fed pneumatically via a separate feed system. Parameters studied, were, reburn zone stoichiometry and reburn fuel fraction. Additionally, the carbon content of the ash was carefully monitored for any effect on burnout at the fuel rich reburn stoichiometries. The NOxreductions achieved with tyres are compared with reburning with coal. NOxreductions up to 80% were achieved with tyres at half of the reburn fuel feed rate required to achieve the same reductions by coal. The results have been evaluated within the context of other studies available in the literature on NOxreburning by bituminous coal, brown coal, gas and biomass.