Modeling of 1 000 MW tower boiler combustion system and study on low-NOx high-efficiency combustion strategy

doi:10.3969/j.issn.2097-0706.2024.12.005

Abstract

Abstract:

Due to the high boiler height and multiple burner layers in tower boilers， traditional control methods struggle to achieve an optimal balance between efficiency and NO_x emissions across a wide load range. To address this issue， a one-dimensional dynamic combustion model of a 1 000 MW tower boiler was developed using Simulink software and validated under steady-state conditions. By analyzing the combustion characteristics under varying burnout air ratios， excess air coefficients， and air distribution modes in main combustion zones， a low-NO_x， high-efficiency combustion strategy was devised for loads ranging from 100% THA to 40% THA. At intervals of 10% THA， the NO_x concentration and unburned carbon rate of the boiler under steady-state conditions were compared before and after combustion optimization.Results showed that after optimization， the coal burnout rate improved by up to 1.14%， and NO_x concentrations significantly decreased at high loads （≥70% THA）， with a maximum reduction of 29 mg/m³. Additionally， the optimized boiler demonstrated an average overall economic gain of 577 yuan/hour， significantly enhancing its economic efficiency. This optimization provides a theoretical foundation and model for establishing a closed-loop combustion control system for boilers.

Key words: combustion optimization, NO_x emissions, tower boiler, ultra-supercritical boiler, one-dimensional combustion model, low-NO_x high-efficiency combustion

CLC Number:

TK123

DING Xu, FU Kangkang, KANG Boshi, LI Xuhui, WANG Jinshi, QIU Binbin. Modeling of 1 000 MW tower boiler combustion system and study on low-NO_x high-efficiency combustion strategy[J]. Integrated Intelligent Energy, 2024, 46(12): 36-44.

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名称	设计煤质	校核煤质
收到基碳/%	58.71	56.39
收到基氢/%	3.23	3.14
收到基氧/%	0.66	0.63
收到基氮/%	6.57	6.40
全硫/%	0.79	0.90
全水分/%	14.80	17.00
空气干燥基水分/%	2.53	2.45
收到基灰分/%	15.24	15.54
干燥无灰基挥发分/%	29.59	29.48
收到基低位发热量/（MJ·kg^-1）	22.50	21.50