尿素溶液高温热分解特性的实验研究  

Investigation on Thermal Decomposition Characteristics of Urea Solution Under High Temperature

作　　者：吕洪坤[1] 杨卫娟[2] 周俊虎[2] 刘建忠[2] 张明[1] 李凤瑞[1] 

机构地区：[1]浙江省电力试验研究院,浙江省杭州市310014 [2]能源清洁利用国家重点实验室(浙江大学),浙江省杭州市310027

出　　处：《中国电机工程学报》2010年第17期35-40,共6页Proceedings of the CSEE

基　　金：国家杰出青年科学基金项目(50525620);国家重点基础研究发展计划项目(2006CB200303)~~

摘　　要：在一管式石英反应器上实验研究了尿素溶液的高温热分解特性以及添加Na2CO3后对相关因素的影响,实验结果表明:保持很高的尿素有效分解率时所能达到的HNCO水解率很低;尿素初始浓度、氧含量对尿素有效分解率无显著影响,而氧含量对热解气中NH3或HNCO比例也无明显影响;氧气在高温下将部分热解气体氧化成了NO,而在一定温度时的自身选择性非催化还原作用产生了部分N2O;Na2CO3可以有效地促进HNCO的水解,添加Na2CO3时,停留时间的延长,提高了HNCO的水解率,降低了HNCO水解反应所需的温度,并且停留时间越大,温度对HNCO水解率的影响就越小,而较低温度工况HNCO水解率对停留时间的敏感度相对更大。Experimental study on thermal decomposition characteristics of urea solution under high temperature and influences of Na2CO3 on related factors was carried out in a quartz tube reactor.The experimental results show：The hydrolysis efficiency of HNCO is very low when keeping high effective-decomposition rate of urea.Urea＇s initial concentration and O2 content both have no marked impact on effective-decomposition rate of urea,and O2 content also has no evident effects on NH3 or HNCO content in urea＇s thermal decomposition gases.O2 oxidizes part of urea＇s thermal decomposition gases to NO under high temperature,and the self-effect of selective non-catalytic reduction produces some N2O.Na2CO3 could improve HNCO＇s hydrolysis reaction effectively,when adding some Na2CO3,the increase of residence time improves the hydrolysis efficiency of HNCO,lowers the needed hydrolysis reaction temperature of HNCO,and the larger residence time,the smaller impact of temperature on HNCO＇s hydrolysis efficiency,moreover the hydrolysis efficiency of HNCO is more sensitive to residence time under low temperature.

关 键 词：尿素 NOx NH3 HNCO 

分 类 号：X511[环境科学与工程—环境工程]