自然风干对马铃薯茎叶成分及厌氧发酵产沼气性能影响的研究

为提高马铃薯茎叶资源化利用水平,文章研究了自然风干对马铃薯茎叶成分及厌氧发酵产沼气性能的影响。实验中首先比较了马铃薯茎叶营养成分和木质化程度随风干时间的变化情况;随后在35℃的中温条件下,分别以不同风干时间的马铃薯茎叶为发酵原料,进行周期为40 d的批式厌氧消化产沼气实验。结果表明:风干时间对马铃薯茎叶成分影响较大,风干时间越久,则可溶性碳水化合物、粗蛋白、粗脂肪等成分含量越低,而中性洗涤纤维含量越高;原料风干程度显著影响厌氧消化启动速度,风干时间越久则发酵启动越慢,但对沼气中甲烷含量影响不大;实验条件下,48 h风干处理组TS产气率最高,达251.70 mL·g^-1,其后依次为24 h风干,新鲜72 h风干和96 h风干处理组,TS产气率分别为227.90 mL·g^-1,154.10 mL·g^-1,193.30 mL·g^-1,和120.50mL·g^-1,各组均未出现体系“过酸化”导致的发酵失败现象。对马铃薯茎叶做适当风干处理后用于厌氧沼气发酵,可有效提高产沼气量,促进农业废弃物资源化利用。

Effects of Natural Air Drying on Components of Potato Stem and Leaf and Its Biogas Fermentation Performance

To improve the utilization level of potato stem and leaf,the effect of natural air drying on components of potato stem and leaf and their biogas production performance were studied in this paper.In the experiment,the changes of nutrient composition and lignification of potato stem and leaves with air drying time were compared.Then,under the medium temperature of 35℃,the potato stem and leaves with different air drying time were used as biogas fermentation materials,and the 40 d of batch fermentation were carried out.The results showed that the air drying time had a great influence on the components of potato stem and leaf.The longer the drying time,the lower the contents of soluble carbohydrate,crude protein,crude fat and other components,while the content of neutral detergent fiber increased.The air drying degree of the raw materials significantly affected the starting speed of anaerobic digestion,the longer the air drying time,the slower the fermentation could start,but it had little effect on the methane content in biogas.Under the experimental conditions,the 48 h air-drying group had the highest TS gas production rate(251.70 mL·g^-1),followed by the 24 h air-drying,fresh,72 h air-drying and 96 h air-drying groups,their gas production rate of TS were 227.90 mL·g^-1,154.10 mL·g^-1,193.30 mL·g^-1,and 120.50mL·g^-1,respectively.There was no fermentation failure caused by system"over acidification"in all groups.These findings suggested that,the properly air-dried potato stem and leaf could effectively increase the biogas production and promote the utilization of agricultural waste resources.