THERMAL SCIENCE

International Scientific Journal

Wei-Shu Wang

,

Zhi-Hao Huang

,

Miao Tian

,

Ji-Hong Wang

,

Shan-Shan Shangguan

,

Ming-Yu Yao

NUMERICAL SIMULATION OF NOX EMISSION CHARACTERISTICS DURING COMBUSTION IN 350 MW SUPERCRITICAL COGENERATION TANGENTIALLY BOILER

ABSTRACT
In light of a 350 megawatt supercritical cogeneration tangential boiler, the combustion and the nitrogen oxides release mechanism in the furnace were numerically simulated. The combustion characteristics were analyzed, and the influencing factors, such as the pulverized coal concentration, the velocity of separated over-fire air and the boiler load, on nitrogen oxides release in the furnace were also systematically studied. The results show that the central airflow in the furnace rises spirally, and an inverted “V” type temperature distribution is formed. The generation of nitrogen oxides can be effectively restrained by increasing the concentration of pulverized coal properly. Compared with the conventional concentration, the concentration of nitrogen oxides at the furnace exit can be reduced by 29.63% by taking high pulverized coal concentration. The concentration of NOx at the furnace exit can be drastically reduced by increasing the velocity of separated over-fire air. When decreasing boiler load, the concentration of NOx at furnace exit declines at first and then increases.
KEYWORDS
supercritical cogeneration tangential boiler, pulverized coal concentration, separated over-fire air, boiler load, NOx emission, numerical simulation
PAPER SUBMITTED: 2019-10-10
PAPER REVISED: 2019-11-22
PAPER ACCEPTED: 2019-12-09
PUBLISHED ONLINE: 2020-01-19
DOI REFERENCE: https://doi.org/10.2298/TSCI191010006W
CITATION EXPORT: view in browser or download as text file
THERMAL SCIENCE YEAR 2020, VOLUME 24, ISSUE Issue 5, PAGES [2717 - 2728]
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Numerical simulation of NOx emission characteristics during combustion in 350 MW supercritical cogeneration tangentially boiler

© 2024 Society of Thermal Engineers of Serbia. Published by the Vinča Institute of Nuclear Sciences, National Institute of the Republic of Serbia, Belgrade, Serbia. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International licence