Numerical simulation study on the influence of pulverized coal particle size on boiler combustion characteristics

Zhihai Cheng,Yang Li,Zhonghan Zhang,S.O Oladokun,S Lu

doi:10.1051/e3sconf/202021801009

Abstract

The influence of pulverized coal particle size on combustion and NOx formation of 660MW tangential combustion ultra-supercritical boiler in a power plant was studied by using commercial software FLUENT. The average particle size of pulverized coal was set at 61μm, 71μm and 80μm, respectively. The results show that with the decrease of pulverized coal particle size, the overall temperature level of the boiler increases, the average temperature of the main combustion zone increases, the temperature of the upper part of the main combustion zone decreases, and the combustion of pulverized coal is more incomplete. However, the probability of particles sticking to the wall and the probability of coking and slagging of the boiler increases. The amount of NOx produced in the main combustion zone decreases, while the amount of NOx produced in the upper part of the main combustion zone increases, while the overall amount of NOx produced increases slightly.

Highlights

Coal is internationally primary energy because of its large supply and low cost[1]
In the process of boiler combustion, the properties of fuel will have a great impact on the combustion characteristics of the boiler
In order to obtain the detailed data of the whole combustion process and reduce the cost, the numerical simulation can be used to study the boiler combustion and obtain the necessary data

Summary

Introduction

Coal is internationally primary energy because of its large supply and low cost[1]. In the past 30 years, China has continued its coal based energy structure[2]. A large number of pollutants, such as smoke, SOx (sulfur oxides) , NOx (nitrogen oxide) and CO2(carbon dioxide), will be produced in the coal-fired power generation process[3]. With the gradual improvement of environmental protection requirements, it has practical significance to improve the efficiency and reduce the pollution in the whole power generation process. Because of the complexity of boiler combustion, some combustion details are hard to be obtained by experimental method. In order to obtain the detailed data of the whole combustion process and reduce the cost, the numerical simulation can be used to study the boiler combustion and obtain the necessary data

Objectives

Results

Conclusion