污泥掺混木屑水解残渣为载体的复合相变材料循环热性能研究

Study on multi-cycle thermal performance of CPCM with sludge/sawdust hydrolysis residue as carrier composted SAT

中文关键词: 污泥水热解残渣  真空吸附法  复合相变材料  热循环性能

英文关键词: Sludge hydrolysis residue  Vacuum adsorption method  Composite phase change material  Thermal cycling performance

中文摘要:

      本文以污泥水热解残渣资源化为目标，采用真空吸附法将污泥/木屑水热解的残渣吸附三水乙酸钠制备复合相变储热材料。对水热解残渣进行BET和粒径分析的表征，通过同步热分析仪、XRD及水浴中熔化-凝固多循环对复合储热材料的储热能力、相变温度、热循环稳定性等性能参数进行分析。实验结果表明，本文制备的复合相变储热材料无需添加增稠剂或悬浮剂等助剂，借助污泥残渣本身特有的均匀粒径和细微粒度特性以及木屑挥发分析出对残渣的造孔重整，作为载体可有效改善常规水合物作为储热材料的相变过冷度和相分离问题。封装尺度对储热材料的相变潜热和稳定性影响较小，100次循环后的潜热实际值与理论计算值（219.8kJ/kg）相差仅为-0.5%~0.4%，化学组分也没有变化，可见该复合储热材料既具有优良的热稳定性也具有可靠的化学稳定性。

英文摘要:

      In this paper, aiming at efficient utilization of sludge hydrolysis residue, the sludge/sawdust hydrolysis residue was used as carrier to adsorb sodium acetate trihydrate by vacuum adsorption method to prepare composite phase change heat storage materials (CPCM). BET and particle size analysis were used to characterize the hydrolysis residue. The heat storage capacity, phase change temperature, thermal cycle and other performance parameters of this CPCM were characterized by synchronous thermal analyzer, XRD and thermal stability of multiple cycles of melting and solidification in water bath. The experimental results show that the CPCM prepared in this paper does not need to add thickener or suspension agent and other additives. The unique uniform particle size and fine aperture characteristics of carrier, which are from the pore and size restructuring by the sawdust volatile releasing from the mixture during hydrolysis, effectively improve the phase change undercooling degree and phase separation problems of conventional hydrate as heat storage material. The encapsulation ways have little influence on the latent heat and stability of the thermal storage material, and the difference between the actual latent heat value and the theoretical value (219.8kJ/kg) after 100 cycles is only -0.5%-0.4%, and the chemical components are also non changed. So the CPCM prepared in this paper has excellent thermal stability and chemical compatibility.