摘要
基于火电企业燃用煤种的多变性,通过河坡超临界350 MW循环流化床(CFB)锅炉掺烧煤种变化前后的参数对比,从风室压力、炉膛差压、床温、受热面参数、灰渣比、NOx排放以及煤种成灰特性等多方面分析了煤种变化对该锅炉运行的影响。结果表明:掺烧皇后矿无烟煤后,床温平均增高17~27℃,减温水量增大,炉膛差压平均降低近30%,循环灰量减少,排渣量增大,飞灰底渣含碳量增大,NOx生成量减少;该无烟煤灰分低,热值大,磨耗速率较低,成灰特性较差,引起物料平衡特性和传热特性的变化。对此,提出了保持相对较高床压运行以维持带负荷能力,入炉煤粒径控制得更细一些,增加500~3200μm之间的质量份额,减少最大粒径档的份额等建议,以扩大CFB锅炉燃煤煤种选择,降低燃料成本。
Based on the variability of coal types used in thermal power plants,the unit parameters before and after changing coal blending scheme in Hepo supercritical 350 MW circulating fluidized bed boiler were compared.The influence of coal variation on the boiler operation was analyzed from several aspects,such as air chamber pressure,furnace differential pressure,bed temperature,heating surface parameters,mass ratio of fly ash to bottom slag,NOx emissions,and coal ash formation characteristics.The results show that,after blending with anthracite from Huanghou mine,the bed temperature increased by an average of 17~27℃and the amount of desuperheating water increased.Besides,the furnace differential pressure decreased by nearly 30%on average and the amount of circulating ash also reduced.Moreover,the discharge slag and the carbon content of fly ash and bottom slag increased,but the NOx generation amount reduced.The anthracite has low ash content,large calorific value,low attrition rate and poor ash formation characteristics,which will cause changes in material balance characteristics and heat transfer characteristics.Therefore,it is recommended to keep relatively high bed pressure to maintain the load capacity and control the fed-coal particle size to be finer,that is,to increase the mass proportion of particles with size of 500~3200μm and reduce the mass proportion of the maximum particle size range,thus to extend the selection of coal types for circulating fluidized bed boilers and reduce the fuel costs.
作者
王鹏程
蔡晋
王珂
李丽锋
张缦
杨海瑞
WANG Pengcheng;CAI Jin;WANG Ke;LI Lifeng;ZHANG Man;YANG Hairui(Shanxi Hepo Power Plant Co.,Ltd.,Yangquan 045000,China;Shanxi Research Institute for Clean Energy Tsinghua University,Taiyuan 030032,China;Department of Energy and Power Engineering,Tsinghua University,Beijing 100084,China)
出处
《热力发电》
CAS
CSCD
北大核心
2021年第3期145-151,共7页
Thermal Power Generation
基金
国家重点研发计划项目(2016YFB0600203)
C9高校科技合作项目(201903D421009)。
关键词
超临界CFB锅炉
煤种变化
炉膛差压
床温
灰渣比
成灰特性
supercritical CFB boiler
coal variation
furnace differential pressure
bed temperature
mass ratio of fly ash to bottom slag
ash formation characteristics
