Heat transfer characteristics of molten slag in rotary cup granulation process
FANG Wei-yang2, WANG Hong1,2, ZHU Xun1,2, DING Yu-dong1,2, LIAO Qiang1,2
1. Ministry of Education Key Laboratory of Low-grade Energy Utilization Technologies and Systems, Chongqing Universty, Chongqing 400030, China; 2. Institute of Engineering Thermophysics, Chongqing University, Chongqing 400030, China
Abstract:Rotary cup atomizers is the most important part in the system of centrifugal granulation integrated with heat recovery from molten slag, but the safety of rotary cup will be affected by heat transfer and temperature distribution with molten slag. Due to the temperature of molten slag over 1 500 ℃, the existing experimental temperature measurement method have been restricted. Therefore, based on numerical simulation method, the flow and heat transfer characteristics was researched as well as the formation of slag crust. The result showed that the thickness of the slag crust and liquid film at the edge of rotary cup decrease as the rotate speed increase. The heat flux and the temperature on the surface of rotary cup increase as the thickness of slag crust decrease. By adding refractory material on the surface of rotary cup, the temperature of the stainless steel in rotary cup have been reduced, thereby achieved the thermal protection of rotary cup.
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