循环流化床锅炉燃用准东煤NOx超低排放技术研究  

Study on NOx Ultra-low Emission Technology of Burning Zhundong Coal in CFB Boiler

作　　者：彭建升 王家兴 程昌业 杨勇军 PENG Jian-sheng;WANG Jia-xing;CHENG Chang-ye;YANG Yong-jun(Yantai Longyuan Power Technology Co.Ltd.,Yantai,China,Post Code:264006;Xinjiang Blue Ridge Tunhe Energy Co.Ltd.,Changji,China,Post Code:831100)

机构地区：[1]烟台龙源电力技术股份有限公司,山东烟台264006 [2]新疆蓝山屯河能源有限公司,新疆昌吉831100

出　　处：《热能动力工程》2020年第10期65-71,共7页Journal of Engineering for Thermal Energy and Power

摘　　要：以燃用准东煤的新疆某热电厂320 t/h循环流化床锅炉为研究对象,分析其NOx生成、抑制机理及原有SCR设备运行情况,进行了低氮燃烧技术与SNCR技术结合的NOx超低排放技术实践。研究表明:通过锅炉二次风系统改造、增设烟气再循环系统、分离器返料系统提效、受热面改造和SNCR改造等措施,NOx初始排放质量浓度从400 mg/m^3降至130 mg/m^3以下,SNCR脱硝后低于50 mg/m^3,床温降低13~32℃,带负荷能力提高至320 t/h,总减温水量从42 t/h降低至22 t/h,分离效率提高,飞灰和返料灰的D50分别降低至24.5和135.9μm,烟气再循环投用未见飞灰底渣含碳量及CO浓度明显增长。With a CFB boiler of firing zhundong coal in Xinjiang as a research object,the mechanism of NOx formation and suppression and the operation of the original SCR equipment were analyzed.The practice of NOx ultra-low emission technology for burning zhundong coal in CFB boiler was conducted by combining SNCR and low-NOx combustion.Results indicate that after the reconstruction of the secondary air system of the boiler,the addition of flue gas recycling system,the improvement of the separator and recycle system,the heating surface reconstruction,and the SNCR optimization,the initial mass concentration of NOx emission is decreased from 400 mg/m^3 to 130 mg/m^3,and is even lower than 50 mg/m^3 after SNCR process.The bed temperature is reduced by 13~32℃.The capacity of boiler is increased to 320 t/h and total spray water flux is decreased from 42 t/h to 22 t/h.The D50 of fly ash and the return ash are decreased to 24.5μm and 135.9μm,respectively,indicating that the separation efficiency is improved.No significant increase is shown in the carbon content of bottom slag or CO concentration for flue gas recycling.

关 键 词：循环流化床锅炉(CFB) 准东煤 低氮燃烧 NOx超低排放 

分 类 号：TK09[动力工程及工程热物理] X511[环境科学与工程—环境工程]