Heat storage is one of the key technologies to improve the storage capacity of renewable energy and to realize the efficient utilization of off-peak power.Molten salt is an efficient heat transfer and storage material.By adding Mg(NO3)2 to NaNO3 at various mass ratios,nine binary nitrate specimens were prepared.The initial melting temperature,primary crystal point and decomposition temperature of mixed nitrates were experimentally studied with differential scanning calorimetry and thermogravimetric analysis.The eutectic properties of mixed salts with different mass ratios were investigated.The variation of specific heat of eutectic molten salts with temperature was experimentally studied.The results showed that within the nine mixed molten salts at different mass ratios,No.05,i.e.Mg(NO3)2 and NaNO3 with the identical mass proportion,can reach the state of eutectic crystal,with the initial melting temperature at 355.4℃,the melting temperature at 364.3℃,the initial crystallization temperature at 368.5℃,and the decomposition temperature at 33.1℃.The remaining binary nitrate specimens which could reach eutectic showed the similar melting temperature at around 340℃,the initial crystal point temperature at 230～250℃,and the decomposition temperature range was in the range of 430～440℃.
[1] 张正敏,王革华,高虎.中国可再生能源发展战略与政策研究[J].经济研究参考,2004(84):26-32.
[2] 闫全英,孙相宇,王立娟,等.三元碳酸盐混合物的制备及热物性研究[J].化工新型材料,2017,45(9):190-192.
[3] 徐芳,陈秋燕,王军涛.低熔点多元混合熔盐的制备及其性能研究[J].可再生能源,2017,35(11):1605-1610.
[4] Dunn R I,Hearps P J,Wright M N.Molten-salt power towers:newly commercial concentrating solar storage[J].Proceedings of the IEEE,2012,100(2):504-515.
[5] 刘先曙.利用硝酸盐储存太阳能[J].科技导报,1994,12(9):53-53.
[6] Herrmann U,Kelly B,Price H.Two-tank molten salt storage for parabolic trough solar power plants[J].Energy,2004,29(5-6):883-893.
[7] Fernndez A G,Rey A,Lasanta I,et al.Corrosion of alumina-forming austenitic steel in molten nitrate salts by gravimetric analysis and impedance spectroscopy[J].Materials & Corrosion,2014,65(3):267-275.
[8] Wu Y T,Li Y,Ren N,et al.Improving the thermal properties of NaNO3-KNO3,for concentrating solar power by adding additives[J].Solar Energy Materials & Solar Cells,2017,160:263-268.
[9] Medrano M,Gil A,Martorell I,et al.State of the art on high-temperature thermal energy storage for power generation.part 2-case studies[J].Renewable & Sustainable Energy Reviews,2010,14(1):56-72.
[10] Bradshaw R W,Cordaro J G,Siegel N P.Molten nitrate salt development for thermal energy storage in parabolic trough solar power systems[C].San Francisco,California,USA:ASME 2009,International Conference on Energy Sustainability Collocated with the Heat Transfer and Interpack09 Conferences.2009.
[11] 汪洋,黄师荣,唐忠锋,等.陶瓷材料在LiF-NaF-KF熔盐中的腐蚀行为研究[J].化工新型材料,2014,42(3):111-113.
[12] Gomez J C,Calvet N,Starace A K,et al.Ca(NO3)2-NaNO3-KNO3 molten salt mixtures for direct thermal energy storage systems in parabolic trough plants[J].Journal of Solar Energy Engineering,2013,135(135):420-431.
[13] Raade J W,Padowitz D.Development of molten salt heat transfer fluid with low melting point and high thermal stability[J].Journal of Solar Energy Engineering,2011,133(3):91-96.
[14] Olivares R I,Edwards W.LiNO3-NaNO3-KNO3,salt for thermal energy storage:thermal stability evaluation in different atmospheres[J].Thermochimica Acta,2013,560(15):34-42.
[15] Fernndez A G,Ushak S,Galleguillos H,et al.Development of new molten salts with LiNO3,and Ca(NO3)2,for energy storage in CSP plants[J].Applied Energy,2014,119(15):131-140.
[16] Takahashi Y,Sakamoto R,Kamimoto M.Heat capacities and latent heats of LiNO3,NaNO3,and KNO3[J].International Journal of Thermophysics,1988,9(6):1081-1090.
[17] Fernndez A G,Ushak S,Galleguillos H,et al.Development of new molten salts with LiNO3,and Ca(NO3)2,for energy storage in CSP plants[J].Applied Energy,2014,119(15):131-140.
[18] 熊亚选,栗博,吴玉庭,等.添加纳米SiO2对四元溴化盐相变热物性的影响[J].化工学报,2017,68(4):1299-1305.
[19] 程晓敏,陶冰梅,朱闯,等.四元碳酸盐相变储热材料的制备及热物性研究[J].化工新型材料,2014,42(6):49-51.
[20] 桑丽霞,蔡萌,任楠,等.混合碳酸盐的改良配制及其热物性分析[J].工程热物理学报,2015,36(3):615-618.
[21] 任楠,王涛,吴玉庭,等.混合碳酸盐的DSC测量与比热容分析[J].化工学报,2011,62(s1):197-202.
[22] 孙李平,吴玉庭,马重芳.太阳能高温蓄热熔融盐优选的实验研究[J].太阳能学报,2008,29(9):1092-1095.
基金资助
北京市自然科学基金重点项目(3151001)
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