文献类型：期刊文献

中文题名：储能硝酸熔盐的热稳定性分析

英文题名：Analysis on thermal stability of molten nitrates at high temperatures

作者：胡憧憬[1,2];孙泽[1,2];黄龙[2,3];张海军[3,4];宋兴福[1,2];于建国[1,2]

机构：[1]华东理工大学资源与环境工程学院,上海200237;[2]国家盐湖资源综合利用工程技术研究中心,上海200237;[3]青海盐湖工业股份有限公司,青海格尔木816000;[4]青海盐湖硝酸盐业股份有限公司,青海格尔木816000

年份：2018

卷号：18

期号：6

起止页码：1315

中文期刊名：过程工程学报

外文期刊名：The Chinese Journal of Process Engineering

收录：CSTPCD;;Scopus;北大核心:【北大核心2017】；CSCD:【CSCD2017_2018】；

基金：国家自然科学基金资助项目(编号:51774144);青海省应用基础研究项目(编号:2017-ZJ-727)

语种：中文

中文关键词：硝酸熔盐;热稳定性;质量损失;机理;热分解;挥发

外文关键词：molten nitrates;thermal stability;mass loss;mechanism;thermal decomposition;vaporization

摘要：研究了商业化储能二元混合硝酸熔盐Solar salt(60%NaNO3-40%KNO3)的热稳定性和恒温热稳定性,采用热重法分析了其热分解温度,通过恒温实验考察了处于开放空气气氛中的NaNO3,KNO3和Solar salt在不同温度下的热稳定性,研究了NaNO3和KNO3在Solar salt高温不稳定性中的作用.结果表明,大于500℃时温度越高,熔盐越不稳定,相同温度下不稳定程度NaNO3>Solar salt>KNO3.温度升高,分解产物NO2-平衡含量增大而达到平衡的时间缩短,O^2-含量很低.Solar salt中硝酸盐热分解和挥发的质量损失比接近1:1,NaNO3是造成体系热分解的主要原因,而KNO3起到抗挥发的作用.
As heat transfer fluids and heat storage mediums,the molten nitrates have been widely used in the solar thermal power generation system in latest years,among which Solar salt system (60%NaNO3-40%KNO3,mass ratio)is the most optimized one. However,there still exists lots of problems in large-scale industrial application,for example,the high temperature stability of Solar salt system is not clear enough.Thus this work aims to investigate the thermal stability of Solar salt system under the conditions of thermal storage and constant high temperatures. The thermal decomposition temperature of Solar salt system was detected by thermo-gravimetric (TG).Meanwhile,constant high temperature experiment of NaNO3,KNO3 and Solar salt were studied in an open system at different temperatures.The constant thermal stability values of Solar salt system and the roles of NaNO3 and KNO3 played in its high-temperature instability were obtained.The high temperature instability of Solar salt system was manifested as mass loss,which was mainly caused by thermal decomposition and volatilization of components.The TG result showed that the thermal decomposition temperature of Solar salt system was 590.6℃ in nitrogen atmosphere.The constant high-temperature experiment showed that Solar salt system was unstable above 500℃ in air,and the higher temperature was,the more unstable of it.The degree of instability was NaNO3>Solar salt system>KNO3 under the same temperature.The content of the decomposed product NO2-eventually reached an equilibrium at some time,and the equilibrium content of NO2- increased while equilibrium time of the reaction decreased as the rising of temperature.However,another decomposed product metal oxides was low.Besides,the mass loss of Solar salt caused by thermal decomposition and volatilization was close to 1:1.In the Solar salt system,NaNO3 was the main cause of thermal decomposition,and KNO3 played the role of anti-volatilization.