摘要
根据对大中型沼气工程中温发酵系统的研究,依照哈尔滨等地区气象条件计算总耗热量,在此基础上为减少沼气罐出料的热量损失,设计了一套污水源热泵余热回收系统。应用Dymola软件对该系统模型的余热回收效率进行模拟分析,评价了污水源热泵全年的工作状况。对哈尔滨地区,在周期为4 h的进出料循环中,污水源热泵系统的COP为2.7~3.0,过热度在3 K左右,热泵系统工作稳定,制热性能系数较高。对哈尔滨地区,11月至转年3月,辅助热源需一直开启;6—8月,压缩机部分负荷运行;4、5、9、10月,根据总耗热量与热泵制热量,确定辅助热源开启时间。在哈尔滨地区,采用压缩机功率为20 kW的热泵系统,最冷的1月能够补偿72%的总耗热量,但小时不保证率较高,需设置辅助热源;采用压缩机功率为33 kW的热泵系统,制热量与总耗热量大体持平,可基本满足中温发酵,但该热泵在6—8月提供的热量超过所需热量的两倍,且COP相比压缩机功率为20 kW时有所降低。
According to the research on mesophilic fermentation system of large and medium-sized biogas project,the total heat consumption was calculated according to the meteorological conditions in Harbin and other regions.On this basis,in order to reduce the heat loss of the biogas tank discharge,a waste heat recovery system for sewage source heat pump was designed.The Dymola software was used to simulate the waste heat recovery efficiency of the system model,and the working conditions of the sewage source heat pump throughout the year were evaluated.For the Harbin area,the COP of the sewage source heat pump system is 2.7 to 3.0,and the superheat degree is about 3 K in the feed and discharge cycle with a period of 4 h.The heat pump system works stably,and the heating performance coefficient is high.For the Harbin area,from November to March,the auxiliary heat source needs to be opened always;from June to August,the compressor partial load operates;in April,May,November and October,the opening time of auxiliary heat source is determined according to the total heat consumption and heat pump heating capacity.In the Harbin area,when heat pump system with compressor power of 20 kW is used,the total heat consumption can be compensated by 72%in coldest January,but the hourly non-guarantee rate is relatively high,and an auxiliary heat source is required.When heat pump system with compressor power of 33 kW is used,the heating capacity and the total heat consumption are roughly the same,which can basically meet the mesophilic fermentation,but the heat provided by the heat pump is more than twice the amount of heat required in June to August,and the COP is lower than the compressor power of 20 kW.
作者
杨博然
陈志光
秦朝葵
YANG Boran;CHEN Zhiguang;QIN Chaokui
出处
《煤气与热力》
2019年第8期J0012-J0018,J0045,共8页
Gas & Heat
关键词
沼气工程
热泵系统模拟
出料余热回收
中温发酵
biogas project
heat pump system simulation
waste heat recovery of discharge
mesophilic fermentation
