摘要
目前采用尿素作为还原剂进行SCR脱硝已经成为一种趋势,利用热解尿素溶液制备SCR还原剂NH3即尿素热解制氨技术在运行管理等方面的优势,使得越来越多的电厂倾向于采用尿素热解技术。利用热重分析方法对尿素溶液的热失重规律进行了实验研究,在简易管式炉和小型尿素热解实验台上研究了尿素溶液高温热分解特性,不同工况(热解温度、尿素溶液浓度、载气流量、添加剂)下尿素溶液热解的氨气产率,从而为尿素溶液热解制氨提供一些基础性的理论依据。结果表明:尿素热重分析发现尿素从室温升至600℃过程中,涉及众多中间反应;热解温度对尿素温度有着显著的影响,随着温度升高,热解效率增大,温度达到650℃时,效率最高;尿素溶液初始浓度对尿素热解效率影响不大,推荐采用50%的初始溶液浓度。
Currently,urea as a reducing agent to prepare SCR DeNOxhas become a trend. Using pyrolysis of urea solution to make SCR reducing agent( NH3),has its advantage on operation and management,so more and more power plants prefer to employ this technology. This paper includeed experimental research on TGA law of urea solution by thermal gravimetric analysis method,and the research of thermal decomposition characteristics of urea solution was finished by using a simple tube furnace and a small urea pyrolysis test bench. Ammonia yield of pyrolysis of urea solution under different conditions( pyrolysis temperature,urea concentration,carrier gas flow and additives) was analysied. In this way,this work provided some fundamental theoretical basis on making ammonia by pyrolysis of urea solution. The experimental results showed that urea thermal decomposition from room temperature to 600 ℃ involve numerous intermediate reactions by thermal gravimetric analysis. The temperature of the urea solution pyrolysis and a significant impact on the efficiency. The efficiency increased with the temperature increasing,and the highest efficiency achieved when the temperature reached 650℃. Initial concentration of urea solution had little effect on the pyrolysis of urea solution,and initial concentration of 50% was recommended.
出处
《环境工程》
CAS
CSCD
北大核心
2014年第7期91-95,共5页
Environmental Engineering
关键词
尿素溶液
热分解
氨气
urea solution
thermal decomposition
ammonia
