Experimental study on NOx reduction from staging combustion of high volatile pulverized coals. Part 1. Air staging
Experimental study on NOx reduction from staging combustion of high volatile pulverized coals. Part 1. Air staging
复制标题
DOI：
10.1016/j.fuproc.2014.04.034
复制
发表时间：
2014-10
影响因子：
7.5
通讯作者：
Jiancheng Yang;R. Sun;Shaozeng Sun;Ningbo Zhao;Ningfeng Hao;Hong Chen;Yong Wang;Haorong Guo
中科院分区：
文献类型：
--
作者：
Jiancheng Yang;R. Sun;Shaozeng Sun;Ningbo Zhao;Ningfeng Hao;Hong Chen;Yong Wang;Haorong Guo
本文研究了还原区化学计量比，停留时间，和煤的特性对氮氧化物排放的空气分级燃烧的情况下的影响。提出了一个综合的NOx还原指数Sz，将最大NOx还原率与煤的特性联系起来。本研究采用多反应段夹带流反应器（EFRM），对我国的低阶煤（四种褐煤和一种次烟煤）和两种高挥发分烟煤进行了研究。结果表明，在空气分级燃烧中，随着还原区化学计量比的减小，NOx的排放量降低，还原率提高。停留时间越长，还原率越高。挥发分含量高的煤，其燃料氮向NOx的转化率较低，有利于降低NOx的排放。燃料综合NOx还原指数越高，NOx还原率越高。特别地，对于低阶煤，取决于煤，在1秒和1.5秒之间的停留时间下实现令人满意的NOx还原。对于高挥发性烟煤，通过增加大于1秒的停留时间而获得的性能增益通常是最小的。此外，空气分级燃烧不会显着降低高挥发分煤的燃尽率。
The paper examines the impact of reduction zone stoichiometric ratio, residence time, and coal characteristics on NOxemissions in the case of air-staged combustion. A comprehensive NOxreduction indexSzwas proposed to correlate the maximum NOxreduction rate and coal characteristics. The study employs the Entrained Flow Reactor with Multiple Reaction Segment (EFRM) and focuses specially on low rank coal (four lignite and one sub-bituminous coal) and two high volatile bituminous coal in China. The results show that in air-staged combustion, the level of NOxemitted drops as the reduction zone stoichiometric ratio decreases, resulting in a high reduction rate. The longer the residence time, the higher the reduction rate will be. Coals with higher volatile content have a lower conversion rate of fuel nitrogen to NOx, benefiting the reduction of NOxemissions. The higher the fuel comprehensive NOxreduction index, the higher is the NOxreduction rate. In particular, satisfactory NOxreduction for the low rank coal is achieved at the residence time between 1 s and 1.5 s, depending on coal. For high volatile bituminous coal, the gain in performance by increase residence time after it is greater than 1 s is generally minimal. Moreover, air-staged combustion does not significantly reduce the burnout rate of the high volatile coal.