基于煤矿乏风热氧化的填充床内置换热器取热特性

发布时间：2018-04-06 04:24

本文选题：蜂窝陶瓷　切入点：填充床　出处：《煤炭学报》2015年06期

【摘要】：基于煤矿乏风热氧化取热过程,搭建了填充床内置换热器稳态取热实验台,取热率最大相对误差为2.50%,实验研究了床层内取热区两侧及取热区内填充蜂窝陶瓷对换热器取热的影响,结果表明:取热区两侧空间填充的蜂窝陶瓷通过增大床层气体物理流速、辐射换热面积、扰动换热器背风侧流场而强化换热器取热,当气体质量流速0.15 kg/(s·m2),温度从613 K升高到1 113 K时,取热区两侧蜂窝陶瓷的存在使换热器取热率比空床增大了2.20%~14.84%,而当气体质量流速增至0.30 kg/(s·m2),温度同样从613 K升高到1 113 K时,取热区两侧蜂窝陶瓷则使换热器的取热率比空床增大了4.92%~10.61%;取热区内填充的蜂窝陶瓷对换热器取热率影响的矛盾两面性决定了取热区内填充的蜂窝陶瓷不会对换热器取热率产生较大影响,也并不总是强化换热器取热,甚至会削弱换热器取热,当气体质量流速为0.15 kg/(s·m2)、温度从613 K升高到1 113 K时,取热区内蜂窝陶瓷的存在使得换热器取热率比空床变化了-1.92%~+4.47%;采用换热器外壁镀银的方法,研究了填充床内置换热器取热过程中传热方式的贡献,结果表明气体质量流速0.15 kg/(s·m2),温度为1 113 K时,换热器取热率中已经有55%的贡献来自辐射,随着温度进一步升高,辐射成为填充床内置换热器取热的主要方式。
[Abstract]:Based on the process of thermal oxidation in coal mine, the steady state heat removal test bench of packed bed heat exchanger is built.The maximum relative error of heat removal rate is 2.50. The effect of honeycomb ceramic on heat recovery in both sides of the bed and in the heating zone is studied experimentally. The results show that the honeycomb ceramic filled in both sides of the heating zone increases the physical velocity of gas in the bed.The heat transfer area of the heat exchanger is enhanced by disturbing the leeward flow field of the heat exchanger. When the gas mass flow rate is 0.15 kg/(s m2, the temperature increases from 613K to 1,113K.The presence of honeycomb ceramics on both sides of the heat removal zone increases the heat removal rate of the heat exchanger by 2.20 and 14.84 compared with the empty bed. When the gas mass flow rate increases to 0.30 kg/(s m2, the temperature also increases from 613K to 1,113K.On the other hand, the heat removal rate of both sides of honeycomb ceramics increased by 4.922 and 10.61 than that of empty bed, and the contradiction between honeycomb ceramics filled in heat recovery zone and heat removal rate determined that the honeycomb ceramics filled in heat recovery zone would not exchange heat.The heat removal rate of the device has a great influence.The heat recovery of heat exchanger is not always enhanced or even weakened. When the gas mass flow rate is 0.15 kg/(s m2, the temperature increases from 613K to 113K.The existence of honeycomb ceramics in the heat removal zone makes the heat removal rate of heat exchanger change from -1.922to 4.47.The contribution of heat transfer mode in the heat recovery process of the heat exchanger with packed bed is studied by silver plating on the outer wall of the heat exchanger.The results show that when the gas mass flow rate is 0.15 kg/(s m2 and the temperature is 1 113K, 55% of the heat removal rate of the heat exchanger has already come from radiation. With the further increase of temperature, radiation has become the main way of heat recovery in the packed bed heat exchanger.
【作者单位】：山东理工大学交通与车辆工程学院;
【基金】：国家高技术研究发展计划(863)资助项目(2009AA063202) 山东省自然科学基金资助项目(ZR2011EL017)
【分类号】：TD727.2

【参考文献】