5 MW级超临界二氧化碳锅炉启动过程中气冷壁堵塞原因分析与对策  

Cause analysis and countermeasures for gas wall blockage of a 5 MW class supercritical carbon dioxide boiler

作　　者：王林[1] 白文刚[1] 李红智[1] 刘岗[1] 宋晓辉[1] 高景辉[1] 王红雨[1] 孟颖琪[1] WANG Lin;BAI Wengang;LI Hongzhi;LIU Gang;SONG Xiaohui;GAO Jinghui;WANG Hongyu;MENG Yingqi(Xi’an Thermal Power Research Institute Co.,Ltd.,Xi’an 710054,China)

机构地区：[1]西安热工研究院有限公司,陕西西安710054

出　　处：《热力发电》2022年第5期142-148,共7页Thermal Power Generation

基　　金：国家重点研发计划项目(2020YFF0218104);国家自然科学基金项目(51806172)。

摘　　要：针对西安热工研究院有限公司(西安热工院)5 MW级超临界二氧化碳(S-CO_(2))锅炉启动过程中气冷壁堵塞问题,结合现场情况开展了原因分析。发现机组充气过程中工质多次发生节流膨胀,制冷降温效果显著,气冷壁底部集箱内存水结冰;CO_(2)温度降低而压力逐步提高,发生液化并封闭了集箱;锅炉点火后,液化的CO_(2)与结冰的水分封闭了通流孔,阻断了工质流动,致使气冷壁无法得到有效冷却,锅炉金属壁温蹿升剧烈。对此,现场实施了小火暖炉、降压闪蒸、末端排水及优化工质充装参数等改进措施,取得了良好效果。经调试调整后,锅炉点火启动正常,金属壁温升速合理,相关经验可供后续同类机组参考。Aiming at solving the gas wall blockage problem occurred in the 5 MW class supercritical carbon dioxide(S-CO_(2)) boiler of Xi’an Thermal Power Research Institute Co., Ltd.(TPRI) during start up process, cause analysis was carried out combining with the field situation. It was found that, during gas charging process of the unit, the working medium throttled and expanded for many times, the cooling effect was remarkable, and the water in the header at the bottom of the gas wall froze. The CO_(2)temperature decreased and the pressure gradually increased, resulting in liquefaction and sealing of the header. After ignition of the boiler, the liquefied CO_(2)and frozen water closed the through-hole and blocked the flow of the working medium, thus the gas wall could not be effectively cooled, and the metal wall temperature of the boiler rose sharply. Based on the above analysis, improvement measures such as small fire heater, depressurization flash, end drainage and optimization of working medium filling parameters were implemented, and good effects were achieved. After debugging and adjustment, the ignition and start-up of the S-CO_(2)boiler turned normal, and the metal wall temperature rise rate was reasonable. The relevant experience can provide reference for similar units in the future.

关 键 词：5 MW 超临界二氧化碳 气冷壁堵塞 液化 结冰 

分 类 号：TK229.2[动力工程及工程热物理—动力机械及工程]