有机物好氧发酵罐废热回收系统的设计与模拟研究

DESIGN AND SIMULATION STUDY ON WASTE HEAT RECOVERY SYSTEM FOR AN ORGANIC AEROBIC FERMENTATION TANK

好氧发酵罐中有机物的发酵会产生大量的废热,为了更好地回收和利用这部分废热,设计了一个好氧发酵罐废热回收系统,并利用Aspen HYSY对系统的废气—水换热器和空气源热泵系统进行模拟和分析。模拟结果表明:在模拟工况(T =50 ℃、T c=55 ℃、T e=7 ℃, T air =25 ℃)下,以R134a为工质的热泵系统具有较高的COP和较低的压缩机排气温度,是该空气源热泵系统的理想循环工质;在南宁地区夏季(T c=55 ℃、T e=8 ℃, T air =32 ℃)和冬季(T c=60 ℃、T e=2 ℃, T air =15 ℃)模拟工况下,该热泵系统COP分别达到4.46和3.79,利用空气源热泵系统和废气-水换热器对好氧发酵罐的废气进行回收和利用是可行的;与传统电加热方式相比,该废热回收系统能有效降低能耗,具有明显的节能和环保效益。

Organic fermentation can release a great quantity of waste heat in aerobic fermentation tank.In order to make better use of the waste heat,this paper designed a waste heat recovery system for the organic aerobic fermentation tank,simulated and analyzed the exhaust gas-water heat exchanger and the air source heat pump system with Aspen HYSY.Results showed that the heat pump system using R134a as the working medium had high COP and low compressor discharge temperature under the simulated condition (T =50℃,T c=55℃,T e=7℃,T air =25 ℃),and R134a was a ideal working medium for the heat pump system.The heat pump system COP attained 4.46 and 3.79 under the summer simulated conditions(T c=55℃,T e=8 ℃,T air = 32 ℃) and winter simulated conditions(T c=60 ℃,T e=2 ℃,T air =15 ℃) in Nanning.The recovery and utilization of organic aerobic fermentation tank by the air source heat pump system and the exhaust gas-water heat exchanger were feasible.Compared with the traditional electric heating,the waste heat system could effectively reduce energy consumption,and had obvious energy conservation and environmental protection benefit.