Fine particulate formation and ash deposition during pulverized coal combustion of high-sodium lignite in a down-fired furnace
Fine particulate formation and ash deposition during pulverized coal combustion of high-sodium lignite in a down-fired furnace
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DOI：
10.1016/j.fuel.2014.11.067
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发表时间：
2015-03-01
期刊：
影响因子：
7.4
通讯作者：
Yao, Qiang
中科院分区：
文献类型：
--
作者：
Li, Gengda;Li, Shuiqing;Yao, Qiang
高储量的准东褐煤富含碱金属和碱土金属元素，在固定燃烧系统中造成严重的结垢和结渣问题。在与实际燃烧器条件相似的25kW顺燃炉中，研究了灰渣沉积倾向及其与富AAEM细颗粒物的关系。准东褐煤中AAEM的高含量(主要是钙)导致了燃烧器入口附近的熔渣，这与其他燃烧高灰熔融烟煤的情况不同。火山灰沉积物被收集在气体温度为800摄氏度的位置，而细颗粒物则在同一位置用两级氮气稀释等速探头采样。准东褐煤灰分的沉积趋势明显高于对照燃料，甚至草本生物质。然后，它与裸沉积管和散装飞灰颗粒的粘性表面有关，这些颗粒是由大量AAEM物种形成的，这增强了沉积倾向。(C)2014爱思唯尔有限公司。保留所有权利。
The high-reserve Zhundong lignite, rich in Alkali and Alkaline Earth Metal (AAEM) elements, causes severe fouling and slagging problems in stationary combustion systems. In this paper, the ash deposition propensity as well as its relation to AAEM-rich fine particulates was investigated in a 25 kW down-fired furnace possessing similar conditions to practical combustors. The high content AAEM (mainly calcium) species in Zhundong lignite results in the molten slag at the vicinity of the burner inlet, differing from other case burning high-ash-fusion (HAF) bituminous coal. The ash deposits were collected at a position with gas temperature of 800 degrees C, whereas the fine particulates were sampled at the same position by a two-stage nitrogen-dilution isokinetic probe. The deposition tendency of ash particles from Zhundong lignite is apparently higher than those from contrast fuels and even herbaceous biomass. It is then related to the sticky surfaces of both bare deposition tube and bulk fly ash particles, forming from large amounts of AAEM species, which enhances the deposition propensity. (C) 2014 Elsevier Ltd. All rights reserved.