Sensitivity analysis of different devolatilisation models on predicting ignition point position during pulverized coal combustion in O2/N2 and O2/CO2 atmospheres
Sensitivity analysis of different devolatilisation models on predicting ignition point position during pulverized coal combustion in O2/N2 and O2/CO2 atmospheres
复制标题
DOI：
10.1016/j.fuel.2011.02.024
复制
发表时间：
2012-11
期刊：
影响因子：
7.4
通讯作者：
R. Jovanović;A. Milewska;B. Świątkowski;A. Goanță;H. Spliethoff
中科院分区：
文献类型：
--
作者：
R. Jovanović;A. Milewska;B. Świątkowski;A. Goanță;H. Spliethoff
全氧燃料燃烧被认为是减少温室气体和污染物排放的一种很有前途的解决方案。纯氧燃烧技术相对于其他煤粉燃烧污染减排技术的主要优点是它可以应用于现有的燃煤电厂。然而，从传统燃烧转变为全氧燃烧带来了重大挑战。其中最重要的是煤粉着火特性的变化。本文介绍了纯氧燃料条件下点火现象的实验和数值分析结果。本文的主要重点是评估数学脱挥发子模型在预测全氧燃烧条件下煤粉火焰着火点方面的有效性。为此，研究了从简单到复杂的几种脱挥发模型在预测燃点位置方面的性能。对不同o2 - n2和o2 - co2条件下的点燃位置和点燃温度的数值测定值与实验室点火试验装置的实验数据进行了比较。所得结果指出，与标准脱挥发模型（单一速率和两个竞争速率）相比，网络脱挥发模型（CPD和FG）给出了更准确的结果。使用FG脱挥发模型可获得最佳性能。因此，新实现的FG模型将用于未来0.5MW中试装置全氧煤粉燃烧数值模拟。
Oxy-fuel combustion is considered as a promising solution to reduce greenhouse-gases and pollutant emissions. The main advantage of oxy-fuel combustion over other technologies for pollution reduction from pulverized coal combustion is that it can be applied to the existing coal-fired power plants. However, switching from conventional to oxy-fired coal combustion brings significant challenges. One of the most important is change of pulverized coal ignition characteristics. This paper presents the results of experimental and numerical analysis of ignition phenomena under oxy-fuel conditions. The main focus of the presented paper is to evaluate the effectiveness of the mathematical devolatilisation sub-model, in predicting the ignition point of pulverized coal flames under oxy-firing conditions. Regarding this, the performance of several devolatilisation models, from simple to more complex ones, in predicting ignition point position have been investigated. Numerically determined values of the ignition point position, and ignition temperature for various O2–N2and O2–CO2conditions were compared with experimental data from the laboratory ignition test facility. Obtained results pointed out that network devolatilisation models (CPD and FG) give more accurate results in comparison with standard devolatilisation models (single rate and two competing rates). The best performance is achieved using FG devolatilisation model. Thus, newly implemented FG model will be used for future numerical simulations of oxy-fuel pulverized coal combustion on 0.5MW pilot plant facility.