Article
Energy & Fuels
Xin Zhang, Zhichao Chen, Guangfei Jiang, Lingyan Zeng, Zhengqi Li
Summary: The effects of central secondary air on the combustion characteristics of a down-fired boiler were studied through experiments. The results showed that reducing the supply of central secondary air can delay the ignition of the coal/air flow, allowing for a higher proportion of blending with bituminous coal.
Article
Thermodynamics
Yanyu Qiao, Song Li, Xinjing Jing, Zhichao Chen, Subo Fan, Zhengqi Li
Summary: This study investigates the combustion characteristics of a retrofitted wall-fired boiler using anthracite as fuel. The results show that stable combustion of anthracite can be achieved at different loads. By adjusting the excess air coefficient and combustion system parameters, combustion efficiency can be improved and pollutant emissions reduced.
Article
Engineering, Chemical
Sheng Liu, Min Kuang, Shengchen Qi, Xiaojuan Zhao
Summary: This study investigates the effects of different flue gas recirculation (FGR) ratios on combustion characteristics and NOx emissions in a CLHC furnace. The findings suggest that increasing FGR lowers combustion temperatures and enhances the reductive atmosphere, but also increases NOx emissions. Based on the results, it is recommended to use lower FGR levels and hot-air dilution in the CLHC furnace.
ASIA-PACIFIC JOURNAL OF CHEMICAL ENGINEERING
(2022)
Article
Energy & Fuels
Xin Zhang, Zhichao Chen, Mingdi Zhang, Lingyan Zeng, Zhengqi Li
Summary: When burning coal for electricity generation under low load conditions, bituminous coal exhibits better combustion stability compared to anthracite, with shorter ignition distance, higher furnace temperature, and lower NOx emissions at the furnace exit.
Article
Energy & Fuels
Bo Zhu, Bichen Shang, Xiao Guo, Chao Wu, Xiaoqiang Chen, Lingling Zhao
Summary: This study investigates the effects of operational parameters on NOx formation and its distribution in furnaces using numerical simulation. A full-scale three-dimensional physical model of a 600 MW supercritical opposed firing pulverized coal boiler is constructed and simulations are performed using Ansys Fluent software. The results show that NOx formation and concentration distribution are mainly influenced by the oxygen concentration and temperature in the furnace.
Article
Energy & Fuels
Tao Liu, Sheng Wang, Ziming Wei, Jie Yu
Summary: In this study, a new combustion system was proposed to solve the problem of high NOx emissions from a down-fired boiler. The system effectively controlled NO emissions but resulted in an increase in the carbon content of fly ash. Further research is needed to reduce the carbon content in fly ash.
Article
Thermodynamics
Xin Zhang, Zhichao Chen, Liankai Li, Lingyan Zeng, Zhengqi Li
Summary: The study found that without over-fire air, a down-fired boiler can still achieve air-staging combustion when burning bituminous coal, leading to different combustion performance under different coal varieties.
COMBUSTION SCIENCE AND TECHNOLOGY
(2022)
Article
Engineering, Chemical
Haopeng Wang, Shuguang Ti, Haoze Jin, Hong Wang, Ke Gao, Yang Liu, Jinfeng Li
Summary: The study established a simulation testbed to investigate the influence of OFA on NOx emissions of boilers, and proposed the use of two-stage OFA for high burnout and low NOx emission.
ASIA-PACIFIC JOURNAL OF CHEMICAL ENGINEERING
(2022)
Article
Thermodynamics
Woojin Lee, Kwonwoo Jang, Woojoo Han, Kang Y. Huh
Summary: The study constructs ROMs for a 500 MWe pulverized coal boiler using POD, Kriging, and RBFN, reproducing the 3D distribution of reacting scalars with small errors. Through parallel computation of the ROM, it can replicate scalar fields at any unexplored operation condition within a few seconds.
CASE STUDIES IN THERMAL ENGINEERING
(2021)
Article
Thermodynamics
Wei Zhang, Jianjun Pei, Zhujun Zhu, Zefu Ye, Changfu You
Summary: This study proposes the use of wall air injection technology in an opposed wall-fired utility boiler to alleviate problems of high temperature corrosion and slagging. Numerical simulations show that injecting wall air reduces gas velocity and temperature near the side wall, improves coal combustion stability, and decreases CO and NO concentrations in the flue gas.
COMBUSTION SCIENCE AND TECHNOLOGY
(2022)
Article
Thermodynamics
Dafu Ma, Shouyu Zhang, Xiang He, Jian Zhang, Xian Ding
Summary: To achieve carbon peaking and carbon neutrality in China, coal-fired units need to respond in real-time to intermittent renewable energy sources. However, operating under ultra-low loads leads to unstable combustion and high NOX emissions. The study found that combustion stability improves as the load decreases, but the low-NOX combustion system's effectiveness weakens.
Article
Energy & Fuels
Chunxing Xu, Meishuang Li
Summary: This paper explains the over-temperature mechanism of a four-wall tangentially fired boiler through numerical simulation and experimental research. It is found that the large cutting radius of the combustion flame and the residual rotation at the furnace outlet are the main causes of over-temperature in the vertical water wall and platen super-heater. By conducting a combustion adjustment test, the over-temperature problem of the boiler heating surface was effectively controlled without equipment modification, ensuring the proper use of the AGC function and the safe and economical operation of the unit.
Article
Chemistry, Multidisciplinary
Wei Jin, Chamin Geng, Ya'ou Wang, Huan Ma, Yunshan Dong, Fengqi Si
Summary: The effects of SOFA yaw and tilt angles on combustion characteristics were numerically investigated. Increasing the yaw angle leads to a separation of high-temperature zones and a more severe gas temperature deviation.
KOREAN JOURNAL OF CHEMICAL ENGINEERING
(2021)
Article
Thermodynamics
Zixiang Li, Xinqi Qiao, Zhengqing Miao
Summary: The ACMA burner arrangement scheme shows superior performance over traditional WTFB, with improved combustion behavior and emission characteristics under low load conditions.
Article
Green & Sustainable Science & Technology
Zhi Wang, Xianyong Peng, Shengxian Cao, Huaichun Zhou, Siyuan Fan, Kuangyu Li, Wenbo Huang
Summary: The study focuses on the selective catalytic reduction (SCR) denitrification efficiency of coal-fired boilers. Accurate predictions of NOx emissions at the SCR inlet can improve denitrification efficiency. Deep learning, random forest (RF) algorithm, and lightweight convolutional neural network (CNN) were used to develop a prediction approach. The experimental results showed that the proposed method reduced model complexity while ensuring prediction accuracy, making it suitable for online optimization of industrial pollutant control and cleaner production.
JOURNAL OF CLEANER PRODUCTION
(2023)