畜禽粪污沼气发电工程中的加热能量平衡分析

Energy Balance Analysis of Power Generation Fueled by Biogas from Anaerobic Livestock Manure Fermentation

文章以江苏某畜禽粪污沼气发电项目为例,分析了畜禽粪污沼气发电工程的中温厌氧消化系统加热能量供给及其影响因素。结果表明:该项目中,总加热能量需求为213.39 GJ·d^(-1),主要为厌氧消化罐的增温保温(75%)和有机肥烘干(25%),其中厌氧消化罐增温保温的热量需求主要是物料增温(85.41%~86.45%)、罐体散热(12.63%~12.9%)和输热管散热(0.68%~1.78%)。因此,当发电余热回收效率为47.4%,回收热量为254.54 GJ·d^(-1)时,沼气发电余热能够满足整个工程的加热能量需求。在其它条件不变的情况,对影响沼气工程加热能量平衡的各主要因素进行单因子分析,结果表明,要保证发电余热至少满足中温厌氧消化增温保温能量需求,则进料TS含量不应低于6.17%,余热回收效率不应低于29.74%,沼气产量达产比例不应低于设计产量的62.74%,原料量不应低于设计原料的18.63%,保温系统保温性能不应低于设计的27.36%。

The heat balance and influence factors of biogas fueled power generation in livestock manure fermentation system were analyzed taking a project in Jiangsu province as an example. The results showed that the total heating energy require- ment of this project was 213.39 GJ · d^-1, including 25% of energy requirement for drying organic fertilizer, 75% for maintaining digester temperature （ constitute of material heating 85.41% ~ 86.45%, the heat loss of digester 12.63% ~ 12.9%, and the heat loss of heat supply pipeline 0.68% ~ 1.78% ）. So, the project could cover the energy requirement when its energy recovery efficiency was 47.4% with power generation of 254.54 GJ · d^-1. And in order to ensure that the recovered energy was enough for maintaining digester temperature, the TS content of feeding material should be larger than 6.17%, the waste heat recovery efficiency should be larger than 29.74%, the actual biogas output should be larger than 62.74% of the designed output, the feeding quantity should be larger than 18.63% of the designed value, and the per- formance of system temperature maintaining should be larger than 27.36% of the designed.