【摘要】 报道第一台NACT(新型灰渣冷却技术)滚筒冷渣机的工业试验结果。工业测试显示,锅炉满负荷运行时NACT滚筒冷渣机的表观传热系数大于95 W/(m~2·K),几乎是现有滚筒冷渣机产品传热系数的2倍。该装置采用扬料板组织灰渣运动,设置迎合抛洒灰渣的对流受热面,将主导热阻由灰渣接触热阻转变为灰渣对流冲刷热阻,大幅度提高了总传热系数。工业测试结果显示:滚筒转速对NACT滚筒冷渣机性能影响巨大。随着滚筒转速提高,灰渣处理量直线升高,但不同转速下的排渣温度升高速率不同;滚筒转速增加,表观传热系数升高,有利于传热过程。增加滚筒对流传热份额,延长灰渣在滚筒内停留时间,是滚筒设计的关键。更多还原

【Abstract】 The industrial test results of the first NACT-based roller type slag cooler were reported. The said results show that when the boiler is operating at its full load,the apparent heat transfer coefficient of the NACT-based roller type slag cooler will be greater than 95 W/( m~2·k),almost two folds of that of the currently-available roller type slag cooler products. The said cooler adopts a material lifting plate to organize the ash and slag movement with a convective heating surface being installed to suit for the flying ash and slag and convert the dominant thermal resistance from the contact thermal resistance of the ash and slag to the ash and slag convective washing thermal resistance,therefore,enhancing by a great margin the total heat transfer coefficient. The industrial test results also indicate that the rotating speed of the roller will exert gigantic influence on the performance of the above-mentioned cooler. With an increase of the rotating speed of the roller,the amount of ash and slag treated will skyrocket like a vertical line but the rates of the temperature rise of the slag discharged at various rotating speeds will be different. The greater the rotating speed of the roller,the bigger the apparent heat transfer coefficient,thus favorable for the heat transfer process. To increase the share of the convective heat transferred by the roller and extend the residence time of the ash and slag in the roller are the key to designing the roller.更多还原