在高炉渣干式粒化余热回收装置的基础上,提出了高炉渣余热驱动的空气布雷顿循环装置,建立了该循环的有限时间热力学模型,对该装置的余热回收性能进行了研究。通过数值计算,分析了压气机压比、压气机进口相对压降(工质质量流率)和余热回收温度对循环功率、热回收效率和循环热效率的影响。结果表明:通过调整压气机进口相对压降和压气机压比,能使热回收效率和循环功率取得最大值;余热回收温度越高,循环功率、热回收效率和循环热效率也越高,同时,压气机进口相对压降的适用范围也越大。并以循环功率最大为目标,优化了压气机压比和压气机进口相对压降,得到了最大循环功率为51.46kW,最大热回收效率为11.98%,对应的循环热效率为20.71%。
Based on dry slag granulation and heat recovery system of BF(blast furnace)slag,an air Brayton cycle driven by waste heat of BF slag is proposed.A finite time thermodynamic(FTT)model of this cycle is established and its heat recovery performance is studied.The effects of the compressor pressure ratio,the compressor inlet relative pressure drop and the heat recovery temperature on the power,the heat recovery efficiency and the thermal efficiency of the cycle are analyzed by numerical examples.It is found that the maximum power and heat recovery efficiency can be reached by adjusting the compressor pressure ratio and the compressor inlet relative pressure drop;The higher heat recovery temperature,the larger the power,the heat recovery efficiency and the thermal efficiency,and also the larger the permissible range of compressor pressure ratio and the compressor inlet relative drop.Moreover,by taking power as objective,the compressor pressure ratio and the compressor inlet relative pressure drop are optimized.Result shows that the maximum power is 51.46 kW,the maximum heat recovery efficiency is 11.98%and the corresponding thermal efficiency is 20.70%.