高温相变胶囊梯级储热系统实验研究

Experimental study of high-temperature phase change capsule gradient heat storage system

中高温相变储热及再利用的方式是低碳经济与工业生产的有效手段。为了更高效地实现工业高温废热的利用,本工作设计搭建并测试了一套高温相变胶囊梯级储热系统,采用了两种不同相变温度的多元碳酸盐材料作为储热材料,对换热工质空气的不同进口温度和进口流量的储放热过程进行了实验研究,研究内容主要包括储热罐中的温度变化、储热量以及储放热过程完成时间。实验结果表明在进口温度为500℃的工况下,系统的储热量可以达到30000 kJ,系统进口流量的提高会缩短储热时间,对系统总储热量影响较小,并分析了不同工况下储热罐体内相变材料平均液相率对系统总储热量的影响。同时测试发现系统中设置的空气预热器使得系统的高温尾气与常温进气进行热量交换,可以有效实现高温尾气的余热利用。相变实验的研究结果为高温相变储热技术的实际应用提供了系统运行参数的影响规律和优化准则,具有很高的参考价值。

The medium and high-temperature phase change heat storage and reuse is effectively achieve low-carbon economies and enhance industrial production.This study designs and tests a high-temperature phase change capsule step heat storage system to efficiently harness industrial high-temperature waste heat.The system uses polycarbonate materials with two different phase change temperatures as heat storage media and experimentally investigates the heat storage and release process under different inlet temperatures and inlet flow rates of the heat transfer air.The study mainly focuses on the temperature changes within the heat storage tank,the heat storage capacity,and the completion time of the heat storage and release processes.Experimental results show that the system can achieve a heat storage capacity of 30000 kJ when the inlet temperature is 500℃.Furthermore,increasing the inlet flow rate of the system reduces the heat storage time while having less influence on the total heat storage capacity of the system.The influence of the average liquid phase rate of the phase change material within the heat storage tank is analyzed about the total heat storage capacity of the system under different operating conditions.Meanwhile,the study highlights the air preheater installed in the system,which facilitates the heat exchange between high-temperature exhaust gas and the normal temperature inlet gas,effectively enabling the waste heat utilization from the high-temperature exhaust gas.The results of the phase change experiment provide valuable insights into the influence law and optimization guidelines of the system operation parameters for the practical application of high-temperature phase change heat storage technology,which has a high reference value.