【摘要】 基于有限元稳态热平衡模型,针对黑龙江省某大型沼气工程,通过分析发酵罐在最低平均气温下的日均总热损失,得出日均温降小于1℃时发酵罐内料液及发酵罐各部分热损失所占比例,为北方大型沼气发酵罐体的结构及保温系统设计提供参考。通过在酸化罐与产气罐之间设置热交换器来替代常规发酵罐体内的加热盘管,对加热系统进行优化分析,避免了加热盘管出现的结壳、腐锈漏水等问题,降低了系统能耗。根据在不同外界气温条件下,发酵罐内料液的日均温降来调整日进料液的加热温度,使进料混合后罐内料液温度达到35℃,探讨罐体外加热料液的关键参数,为北方大型沼气工程加热系统的设计及优化提供参考依据。更多还原

【Abstract】 For a large-scale biogas project in Heilongjiang province,based on finite element model of steady-state thermal balance,the total daily mean heat loss of a digester was analyzed under the condition of the lowest mean temperature.Results show that the daily mean temperature reduction of the fermentative materials is less than 1 °C.The proportion of heat loss in different part of the digester is also obtained.According to the results,the digester structure and insulating system for this large-scale biogas project was designed.The heating system was optimized by replacing the heat exchanger,which was located between the acidification digester and biogas digester,with general heating circular pipeline.Thus,the incrustation and rust leakage of the pipeline could be avoided and the energy consumption was reduced.The temperature of the heating material was adjusted according to daily mean temperature drop of the fermentative material in the digester to make the temperature of the mixed fermentative material be up to 35 °C.The key parameters of the heating material for external heating of digester were investigated.Our study can provide reference for the design and optimization of the heating system of large-scale biogas project in northeast China.更多还原