Preparation and performance optimization of phase change cold storage materials with sodium sulfate hydrate salt

doi:10.16085/j.issn.1000-6613.2022-0183

Abstract

Abstract:

A new formulation for the preparation of phase change cold storage materials based on sodium sulfate decahydrate (SSD) was proposed for air-conditioning system applications, and all aspects of the material's performance were optimized. The nucleating agent ratio was first determined using the step-cooling curve method to eliminate subcooling of the material. On this basis, the effect of different types and levels of thickening agents [sodium polyacrylate (PAAS), polyacrylamide (PAM), carboxymethyl cellulose (CMC), polyanionic cellulose (PAC) and xanthan gum (XG)] on the phase separation and latent heat of phase change of the material was investigated and analyzed. Then, the melting point controller ammonium chloride and potassium chloride were added to change the phase change temperature of sodium sulfate decahydrate, and the phase change material was formulated to meet the air-conditioning temperature zone. Finally, expanded graphite (EG) was added to further improve the thermal conductivity and stability of the material, and the thermal cycling tests were carried out. The experimental results showed that the addition of 3% (mass fraction) borax was the most effective in reducing the subcooling of the material. The addition of 1.0%—2.0% (mass fraction) PAAS could eliminate the phase separation phenomenon of the material and had the less effect on the latent heat of phase change of the material. The material had a high thermal conductivity and shape stability when the mass ratio of SSD-BPA∶EG was 93∶7. The phase change temperature of the optimized composite phase change storage material was 7.4℃, the latent heat of phase change was 117.4J/g and the thermal conductivity was 1.876W/(m·K). The phase change temperature of the material remains stable after 200 cycles and the latent heat decay rate was 14.05%.

Key words: phase change materials, cold storage, sodium sulfate decahydrate, phase change temperature, latent heat of phase change

摘要：

针对空调系统应用场合，提出一种以十水硫酸钠（sodium sulfate decahydrate，SSD）为主材的相变蓄冷材料新型制备配方，并对材料的各方面性能加以优化。首先采用步冷曲线法确定成核剂比例，消除材料过冷现象，在此基础上研究分析了不同种类、含量的增稠剂[聚丙烯酸钠（PAAS）、聚丙烯酰胺（PAM）、羧甲基纤维素（CMC）、聚阴离子纤维素（PAC）、黄原胶（XG）]对材料相分离及相变潜热的影响，接着加入熔点控制剂氯化铵、氯化钾改变十水硫酸钠的相变温度，调配出满足空调温区的相变材料，最后加入膨胀石墨（expanded graphite，EG）进一步改善材料的导热性和稳定性，并进行了热循环测试。结果表明：添加质量分数3%的硼砂对降低材料过冷度效果最佳；添加质量分数1.0%~2.0%的PAAS可以消除材料的相分离现象，且对材料的相变潜热影响较小。SSD-BPA∶EG质量比为93∶7时材料具有较高的导热性和形状稳定性。经优化后复合相变蓄冷材料的相变温度为7.4℃，相变潜热为117.4J/g，热导率为1.876W/(m·K)，经200次循环后材料的相变温度保持稳定，潜热衰减率为14.05%。

关键词: 相变材料, 蓄冷, 十水硫酸钠, 相变温度, 相变潜热

CLC Number:

TK02

YANG Jin, YIN Yonggao, CHEN Wanhe, WANG Jingyuan, CHEN Jiufa. Preparation and performance optimization of phase change cold storage materials with sodium sulfate hydrate salt[J]. Chemical Industry and Engineering Progress, 2022, 41(11): 5977-5985.

杨晋, 殷勇高, 陈万河, 王静远, 陈九法. 硫酸钠水合盐相变蓄冷材料的制备及性能优化[J]. 化工进展, 2022, 41(11): 5977-5985.

Figures/Tables 15

References 24

1	唐瑞, 桂树强, 颜俊, 等. 相变材料应用于空调蓄冷中的研究进展[J]. 建筑节能, 2020, 48(1): 57-61.
	TANG Rui, GUI Shuqiang, YAN Jun, et al. Research progress of phase change materials applied in air-conditioning cold storage[J]. Building Energy Efficiency, 2020, 48(1): 57-61.
2	王温馨, 齐红, 丁益民. 水合盐相变储能材料的研究进展[J]. 化学通报, 2021, 84(4): 330-338.
	WANG Wenxin, QI Hong, DING Yimin. Research progress in hydrated salt composite phase change energy storage materials[J]. Chemistry, 2021, 84(4): 330-338.
3	杨天润, 孙锲, WENNERSTEN Ronald, 等. 相变蓄冷材料的研究进展[J]. 工程热物理学报, 2018, 39(3): 567-573.
	YANG Tianrun, SUN Qie, WENNERSTEN Ronald, et al. Review of phase change materials for cold thermal energy storage[J]. Journal of Engineering Thermophysics, 2018, 39(3): 567-573.
4	ZHAI X Q, WANG X L, WANG T, et al. A review on phase change cold storage in air-conditioning system: materials and applications[J]. Renewable and Sustainable Energy Reviews, 2013, 22: 108-120.
5	NIE Binjian, PALACIOS Anabel, ZOU Boyang, et al. Review on phase change materials for cold thermal energy storage applications[J]. Renewable and Sustainable Energy Reviews, 2020, 134: 110340.
6	CHEN Weicheng, LIANG Xianghui, WANG Shuangfeng, et al. SiO₂ hydrophilic modification of expanded graphite to fabricate form-stable ternary nitrate composite room temperature phase change material for thermal energy storage[J]. Chemical Engineering Journal, 2021, 413: 127549.
7	LI Gang, ZHANG Binbin, LI Xiang, et al. The preparation, characterization and modification of a new phase change material: CaCl₂·6H₂O-MgCl₂·6H₂O eutectic hydrate salt[J]. Solar Energy Materials and Solar Cells, 2014, 126: 51-55.
8	EL-BASSUONI Abdel Monem A, TAYEB Aghareed M, HELWA Nawal H, et al. Modification of urea-sodium acetate trihydrate mixture for solar energy storage[J]. Renewable Energy, 2003, 28(10): 1629-1643.
9	张寅平. 相变贮能: 理论和应用[M]. 合肥: 中国科学技术大学出版社, 1996.
	ZHANG Yinping. Phase change energy storage: theory and applications[M]. Hefei: University of Science and Technology of China Press, 1996.
10	喻彩梅, 章学来, 华维三. 十水硫酸钠相变储能材料研究进展[J]. 储能科学与技术, 2021, 10(3): 1016-1024.
	YU Caimei, ZHANG Xuelai, HUA Weisan. Research progress of sodium sulfate decahydrate phase change material[J]. Energy Storage Science and Technology, 2021, 10(3): 1016-1024.
11	刘剑虹, 刘瑞虹, 王超会, 等. Na₂SO₄·10H₂O复合相变储能体系的热力学测试[J]. 节能, 2007, 26(9): 13-14, 24.
	LIU Jianhong, LIU Ruihong, WANG Chaohui, et al. Thermodynamics test of Na₂SO₄·10H₂O phase change compound system[J]. Energy Conservation, 2007, 26(9): 13-14, 24.
12	谢奕, 史波, 冯叶. 空调用共晶盐蓄冷材料的增稠特性实验研究[J]. 建筑节能, 2020, 48(4): 9-13, 32.
	XIE Yi, SHI Bo, FENG Ye. Experimental study on thickening characteristics of eutectic salt cold storage material for air conditioning[J]. Building Energy Efficiency, 2020, 48(4): 9-13, 32.
13	ZHU Na, HU Pingfang, LEI Yu, et al. Numerical study on ground source heat pump integrated with phase change material cooling storage system in office building[J]. Applied Thermal Engineering, 2015, 87: 615-623.
14	张志同, 王瑾, 柳建华, 等. Na₂SO₄·10H₂O相变蓄冷材料的研究进展[J]. 建筑节能, 2016, 44(8): 55-59.
	ZHANG Zhitong, WANG Jin, LIU Jianhua, et al. Research progress of Na₂SO₄·10H₂O phase change cooling storage materials[J]. Building Energy Efficiency, 2016, 44(8): 55-59.
15	TELKES Maria. Nucleation of supersaturated inorganic salt solutions[J]. Industrial & Engineering Chemistry, 1952, 44(6): 1308-1310.
16	VAVOURAKI A I, KOUTSOUKOS P G. Kinetics of crystal growth of mirabilite in aqueous supersaturated solutions[J]. Journal of Crystal Growth, 2012, 338(1): 189-194.
17	李玉婷, 周永全, 葛飞, 等. 无机水合盐相变储能材料的过冷及相分离研究进展[J]. 盐湖研究, 2018, 26(1): 81-86.
	LI Yuting, ZHOU Yongquan, GE Fei, et al. Supercooling and phase separation of inorganic salt hydrates as phase change materials[J]. Journal of Salt Lake Research, 2018, 26(1): 81-86.
18	LI Chuanchang, ZHANG Bo, XIE Baoshan, et al. Tailored phase change behavior of Na₂SO₄·10H₂O/expanded graphite composite for thermal energy storage[J]. Energy Conversion and Management, 2020, 208: 112586.
19	刘欣, 徐涛, 高学农, 等. 十水硫酸钠的过冷和相分离探究[J]. 化工进展, 2011, 30(S1): 755-758.
	LIU Xin, XU Tao, GAO Xuenong, et al. Study on supercooling and phase separation of Na₂SO₄·10H₂O[J]. Chemical Industry and Engineering Progress, 2011, 30(S1): 755-758.
20	郑涛杰, 陈志莉, 刘强, 等. 水合盐相变储能材料的增稠剂优选研究[J]. 太阳能学报, 2018, 39(7): 1781-1787.
	ZHENG Taojie, CHEN Zhili, LIU Qiang, et al. Study on optimum agent of thickener for salt hydrate phase change energy storage material[J]. Acta Energiae Solaris Sinica, 2018, 39(7): 1781-1787.
21	Håkon SELVNES, ALLOUCHE Yosr, MANESCU Raluca Iolanda, et al. Review on cold thermal energy storage applied to refrigeration systems using phase change materials[J]. Thermal Science and Engineering Progress, 2021, 22: 100807.
22	LI Yaxi, LI Chuanchang, LIN Niangzhi, et al. Review on tailored phase change behavior of hydrated salt as phase change materials for energy storage[J]. Materials Today Energy, 2021, 22: 100866.
23	李文琛, 蔡一凡, 严泰森, 等. 三水合醋酸钠/膨胀石墨复合相变材料的制备及其储热性能[J]. 上海交通大学学报, 2020, 54(10): 1015-1023.
	LI Wenchen, CAI Yifan, YAN Taisen, et al. Preparation and thermal storage properties of sodium acetate trihydrate-expanded graphite as phase change composite[J]. Journal of Shanghai Jiao Tong University, 2020, 54(10): 1015-1023.
24	王佩祥, 冯秀娟, 朱易春, 等. 利用膨胀石墨改进十二水磷酸氢二钠复合相变材料的蓄热性能[J]. 材料导报, 2020, 34(18): 18044-18048.
	WANG Peixiang, FENG Xiujuan, ZHU Yichun, et al. Improvement of heat storage performance of disodium hydrogen phosphate dodecahydrate composite phase change materials with expanded graphite[J]. Materials Reports, 2020, 34(18): 18044-18048.

水合盐	相变温度/℃	相变潜热/kJ·kg^-1	价格/CNY·kg^-1
CaCl₂·6H₂O	29.6	191	350
Na₂SO₄·10H₂O	32.4	251	40
Zn（NO₃）₂·6H₂O	36.4	130	170
Na₂HPO₄·12H₂O	36.5	264	60
CH₃COONa·3H₂O	58	266	35
Ba（OH）₂·8H₂O	78	265	50

水合盐	相变温度/℃	相变潜热/kJ·kg^-1	价格/CNY·kg^-1
CaCl₂·6H₂O	29.6	191	350
Na₂SO₄·10H₂O	32.4	251	40
Zn（NO₃）₂·6H₂O	36.4	130	170
Na₂HPO₄·12H₂O	36.5	264	60
CH₃COONa·3H₂O	58	266	35
Ba（OH）₂·8H₂O	78	265	50

用途	材料名称	分子式	分子量	生产厂家
实验主材	十水硫酸钠	Na₂SO₄·10H₂O	322	上海展云
成核剂	硼砂	Na₂B₄O₇·10H₂O	381	成都科隆
增稠剂	聚丙烯酸钠	C₃H₃NaO₂	94	罗恩
	聚丙烯酰胺	C₃H₅NO	71	罗恩
	羧甲基纤维素	C₈H₁₆NaO₈	263	上海麦克林
	聚阴离子纤维素	Al₂（OH）₆Cl	191.5	上海麦克林
	黄原胶	C₃₅H₄₉O₂₉	933	上海麦克林
熔点控制剂	氯化铵	NH₄Cl	53.5	罗恩
	氯化钾	KCl	74.5	国药集团
高导热基体	膨胀石墨	C	12	阿拉丁

用途	材料名称	分子式	分子量	生产厂家
实验主材	十水硫酸钠	Na₂SO₄·10H₂O	322	上海展云
成核剂	硼砂	Na₂B₄O₇·10H₂O	381	成都科隆
增稠剂	聚丙烯酸钠	C₃H₃NaO₂	94	罗恩
	聚丙烯酰胺	C₃H₅NO	71	罗恩
	羧甲基纤维素	C₈H₁₆NaO₈	263	上海麦克林
	聚阴离子纤维素	Al₂（OH）₆Cl	191.5	上海麦克林
	黄原胶	C₃₅H₄₉O₂₉	933	上海麦克林
熔点控制剂	氯化铵	NH₄Cl	53.5	罗恩
	氯化钾	KCl	74.5	国药集团
高导热基体	膨胀石墨	C	12	阿拉丁

仪器名称	生产公司	型号	精度
磁力搅拌水浴锅	恩谊仪器	HH-2J	温度稳定性±0.5℃
低温恒温槽	赛勒仪器	SLDC-0520	温度稳定性±0.01℃
微量热仪	法国Setaram	uDSC7 Evo	温度精度<0.01℃，热焓精度<0.05%
热导率测试仪	西安夏溪电子	TC3000E	3%
安捷伦数据采集仪	Agilent	34970A	温度系数0.03℃
热场发射扫描电子显微镜	美国FEI	quanta 400 FEG	重复精度： 2μm（X/Y方向）