点击上方蓝色文·字关注我们吧
Title: Flame Morphology and Characteristic of Co-Firing Ammonia with Pulverized Coal on a Flat Flame Burner
题目：平焰燃烧器氨煤混燃火焰形态与特性研究
Authors: WANG Shengye, CUI Mingshuang, LIU Pengzhong, DI Yi, NIU Fang
作者：王圣烨，崔名双，刘鹏中，底一，牛芳
单位：煤炭科学研究总院，北京天地融创科技股份有限公司，国家能源煤炭高效利用与节能减排技术装备重点实验室
Journal of Thermal Science, 2024, 33(5): 1935-1945.
👇点击下载全文
摘要
Abstract: Ammonia as a new green carbon free fuel co-combustion with coal can effectively reduce CO2 emission, but the research of flame morphology and characteristics of ammonia-coal co-combustion are not enough. In this work, we studied the co-combustion flame of NH3 and pulverized coal on flat flame burner under different oxygen mole fraction (Xi,O2) and NH3 co-firing energy ratios (ENH3). We initially observed that the introduction of ammonia resulted in stratification within the ammonia-coal co-combustion flame, featuring a transparent flame at the root identified as the ammonia combustion zone. Due to challenges in visually observing the ignition of coal particles in the ammonia-coal co-combustion flame, we utilized Matlab software to analyze flame images across varying ENH3 and Xi,O2. The analysis indicates that, compared to pure coal combustion, the addition of ammonia advances the ignition delay time by 4.21 ms to 5.94 ms. As ENH3 increases, the ignition delay time initially decreases and then increases. Simultaneously, an increase in Xi,O2 results in an earlier ignition delay time. The burn-off time and the flame divergence angle of pulverized coal demonstrated linear decreases and increases, respectively, with the growing ammonia ratio. The addition of ammonia facilitates the release of volatile matter from coal particles. However, in high-ammonia environments, oxygen consumption also impedes the surface reaction of coal particles. Finally, measurements of gas composition in the ammonia-coal flame flow field unveiled that the generated water-rich atmosphere intensified coal particle gasification, resulting in an elevated concentration of CO. Simultaneously, nitrogen-containing substances and coke produced during coal particle gasification underwent reduction reactions with NOx, leading to reduced NOx emissions.
摘要：氨气作为一种新型绿色无碳燃料，与煤掺烧可以有效减少二氧化碳排放，但对于氨气与煤掺烧的火焰形态和特性的研究还不够充分。在本研究中，我们在平焰燃烧器上研究了不同氧气摩尔分数和掺氨比下氨煤掺烧火焰。首先，我们发现随着氨气的加入，氨煤混燃火焰产生了分层现象，在火焰根部存在透明火焰区域被认定为氨气燃烧区。由于氨煤混燃火焰中无法直接观测到煤粉颗粒的着火情况，因此使用Matlab软件分析不同掺氨比和氧气摩尔分数下的火焰图像。分析结果表明，与纯煤燃烧相比，氨气的加入使点火延迟时间提前4.21ms-5.94ms。随着掺氨比的增加，点火延迟时间先减少后增加。同时，氧气摩尔分数的增加也使点火延迟时间提前，煤粉的燃尽时间和火焰扩展角度分别随着氨气比例的增加呈线性减少和增加。氨气的加入促进了煤颗粒挥发物的释放，在高掺氨比的条件下，氧气的消耗也阻碍了煤颗粒的表面反应。最后，对氨煤混燃火焰流场中气体组分进行测定，发现燃烧过程中生成的富含水的环境加剧了煤粉的气化反应，导致CO浓度升高。同时，煤颗粒气化过程中生成的含氮物质和焦炭与NOx发生还原反应，减少了NOx的排放。
（👆下滑看摘要，点击文章顶部题目链接看文章全文）
图片展示
引用格式
WANG Shengye, CUI Mingshuang, LIU Pengzhong, DI Yi, NIU Fang, Flame Morphology and Characteristic of Co-Firing Ammonia with Pulverized Coal on a Flat Flame Burner, Journal of Thermal Science, 2024, 33(5): 1935-1945.
👇点击“阅读原文”可进入官网
