摘要
CFB机组压火热备技术是一种极深度调峰技术,可实现对外近零功率输出。然而,在压火期间受蒸汽参数限制,目前压火时长仅有1 h~2 h。为解决压火时长短的问题,构建了一种CFB机组耦合太阳能储热的长周期压火热备技术方案。在压火运行期间,通过光热生成高参数辅助蒸汽,使锅炉原生蒸汽与辅助蒸汽协同维持汽轮机运行,从而突破传统CFB机组压火时长限制。为探究耦合储热的CFB机组的压火运行特性,使用EBSILON建立了该机组的热力系统模型,获得了机组主蒸汽流量在20 t/h~40 t/h范围内的主要运行参数。建立了火用分析模型,揭示了极端低负荷下CFB机组火用损分布特性,量化了关键部件的火用性能指标。结果表明:压火工况下,机组最小输出功率仅3.3 MW,扣除厂用电后,对外可实现近零输出。火用分析表明,随着主蒸汽流量增加,机组关键部件的火用损失和火用效率都呈上升趋势。其中,给水加热器的火用效率最高,均在93%以上,而高压缸的火用效率仅有50%左右。机组的火用损率从高到低依次为:凝汽器、汽轮机、熔盐换热器、给水加热器。
CFB banked-fire hot-standby technology is an extremely deep peaking technology that can achieve near-zero power output.However,due to the limitation of steam parameters during banked-fire operation,the safe operation time of steam turbine can be maintained only about 1 h‒2 h.To address the above issues,a long-period banked-fire technology scheme for CFB power plants coupled with thermal storage has been proposed.During banked fire operation,high-parameter regenerative steam generated through solar-thermal integration synergistically maintains turbine operation with boiler primary steam,thereby breaking through the duration limitations of conventional CFB units in banked fire conditions.To explore operation characteristics of the above unit,a thermodynamic system model of the unit was established using the EBSILON,obtaining key operational parameters under main steam flow rates ranging from 20 t/h to 40 t/h.An exergy analysis model was established to reveal exergy destruction distribution patterns in CFB units under ultra-low load conditions,with quantitative evaluation of exergy performance indicators for critical components.Results demonstrate that the unit achieves a minimum output of 3.3 MW during banked fire operation,realizing near-zero external power output after deducting auxiliary power consumption.Exergy analysis reveals that both exergy destruction and exergy efficiency of key components exhibit increasing trends with rising main steam flow rates.The feedwater heater demonstrates superior exergy efficiency exceeding 93%,while the high-pressure(HP)turbine shows relatively low efficiency of approximately 50%.Component exergy destruction rates follow this descending order from high to low:condenser,steam turbine,molten salt-water heat exchanger,feedwater heater.
作者
韩佩兴
冯浩
钟旭东
郭俊菲
王兴
黄中
柯希玮
HAN Peixing;FENG Hao;ZHONG Xudong;GUO Junfei;WANG Xing;HUANG Zhong;KE Xiwei(Shanxi Research Institute of Huairou Laboratory,030032 Taiyuan,China;Jinneng Holding Power Group,030006 Taiyuan,China;China Energy Science and Technology Research Institute Company Limited,210023 Nanjing,China;Department of Energy and Power Engineering,Tsinghua University,100084 Beijing,China;Beijing Huairou Laboratory,101499 Beijing,China)
出处
《煤炭转化》
北大核心
2025年第5期3-12,共10页
Coal Conversion
基金
中国科协青年人才托举工程项目(2024-2026QNRC001).
关键词
循环流化床
灵活调峰
近零出力
火用分析
模拟
circulating fluidized bed
deep peak regulation
near-zero output
exergy analysis
simulation
作者简介
第一作者:韩佩兴,实习研究员,E-mail:hanpeixing@sxri.hrl.ac.cn;通信作者:柯希玮,博士、副研究员,E-mail:kexiwei@sxri.hrl.ac.cn。
