在改造生物质炉的各种运行条件下,对焦炭转换和NOx排放的数值优化
Viet Thieu Trinh1,2, Byoung-Hwa Lee3, Seung-Mo Kim3
1School of Mechanical Engineering, Pusan National University, 2, Busandaehak-ro 63 beon-gil, Geumjeong-gu, Busan 46241, Republic of Korea.
ACS omega
|June 5, 2023
概括
用生物质改装化石炉可以改善电力供应并降低成本. 最佳的燃烧条件,特别是40%的二次空气比率,可以显著减少未燃烧的碳和底层灰,同时最大限度地提高燃烧转化率.
科学领域:
- 能源工程 能源工程
- 燃烧科学 燃烧科学
- 环境技术 环境技术
背景情况:
- 用生物质改装化石燃料炉对于解决电力短缺和降低发电厂成本至关重要.
- 在改装炉中的生物质燃烧面临诸多挑战,包括大量未燃烧的碳,大量的底层灰和氧化 (NOx) 排放.
研究的目的:
- 为了确定一台125MWe粉碎生物质炉的最佳燃烧条件,该炉是从一个石下燃炉改装而来的.
- 评估二次空气比率和燃烧器待机位置对燃烧效率和排放的影响.
主要方法:
- 利用计算流体动力学 (CFD) 与商业软件 (流体ANSYS) 模拟生物质燃烧.
- 研究了空气分布,重点关注二次空气比率和燃烧器待机配置.
- 计算的关键参数:生物质灰质量,焦炭转化,高区域温度和NOx形成/减少.
主要成果:
- 40%的二次空气比率 (R案例) 显著降低了底层灰到247公斤/小时,并增加了煤炭转化到97.33%.
- 案例R显示出优异的空气生物质混合,以较低的标准偏差温度 (240K) 表示.
- 最佳条件 (燃烧器A待机,40%的二次空气比率) 产生了98.43%的煤炭转化,每小时204公斤的底层灰和106ppm的NOx.
结论:
- 将二次空气比率优化至40%是改装炉高效生物质燃烧的关键.
- 选择的最佳情况证明了高碳转化,低底灰和减少氧化物排放之间的成功平衡.
- 差价合约 (CFD) 建模为确定生物质改装发电厂最佳运行参数提供了宝贵的工具.
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