摘要
为提高玉米芯和鸡粪厌氧发酵甲烷产率,研究了玉米芯和鸡粪混合发酵性能。实验结果表明,玉米芯与鸡粪最佳混合比为5∶1,沼气和甲烷产率最高,分别是200mg/g和121.2mL/g(玉米芯/鸡粪,VS,下同),与单一鸡粪厌氧发酵相比,沼气产量提高了700%,玉米芯与鸡粪混合发酵有助于更多的生物质向甲烷转化。玉米芯与鸡粪在最佳比例下混合发酵时挥发性脂肪酸(VFAs)最高达2.56g/L,乙酸在VFAs中起主导作用。适当的鸡粪添加有助于体系氨氮含量增大和甲烷菌活性提高,过多鸡粪添加不利于甲烷总产量的提高。氨氮与VFAs的中和作用促进了体系的pH稳定。底物进料量对沼气产率有明显的影响,混合底物进料量为50g/L时总产气量最高,为7800mL,对应的甲烷体积分数为68.7%,而进料量为20g/L时沼气产率和甲烷产率最高,分别为325mg/g和184.3mL/g。玉米芯与鸡粪混合发酵能够改善碳氮底物(C/N)的发酵比、提高微量金属元素含量,是甲烷产率提高的主要原因。
To improve the biomethane yield of corncob and fowl dung, anaerobic co-digestion of corncob and fowl dung was investigated. Results showed that the highest biogas and methane yields were obtained at the ratio of 5∶1(corncob/fowl dung, based on VS), corresponding to 200.0 mg/g and 121.2 mL/g,respectively. The biogas production of co-digestion was improved by 700% in comparison of single digestion of fowl dung. Anaerobic co-digestion of corncob and fowl dung benefits the conversion of biomass to methane. With the optimum corncob/fowl dung of 5∶1, the highest VFAs were 2.56 g/L, which was dominated by acetate. Appropriate addition of fowl dung was in favor of increasing ammonia concentration as well as the activity of methanogen. However, excessive addition of fowl dung would reduce the total biomethane production. The neutralization of ammonia with VFAs maintained the codigestion system in stable condition. The amount of feedstock could significantly influence the biogas yield. The highest biogas yield could be achieved at the loading of 50 g/L. The corresponding biogas production and methane content of 7800 mL and 68.7%, respectively. However, the biogas yield and methane yield were the highest when feeding was 20 g/L,whichwere325 mg/gand184.3 mL/g,respectively.The C/N ratio could be optimized and the concentration of trace elements could be enriched by codigestion of corncob and fowl dung, resulting in the improvement of methane yield.
作者
田玉菲
杨莉
周鸣人
张存胜
TIAN Yufei;YANG Li;ZHOU Mingren;ZHANG Cunsheng(School of Food and Biological Engineering,Jiangsu University,Zhenjiang 212013,Jiangsu,China;Jiangsu Huizhi Intellectual Property Service Co.,Ltd.,Zhenjiang 212013,Jiangsu,China;Jingjiang College,Jiangsu University,Zhenjiang 212013,Jiangsu,China)
出处
《化工进展》
EI
CAS
CSCD
北大核心
2019年第6期2898-2904,共7页
Chemical Industry and Engineering Progress
基金
国家自然科学基金青年基金(51608232)
江苏省自然科学基金青年基金(BK20150487)
江苏高校优势学科建设工程项目
关键词
玉米芯
鸡粪
甲烷
厌氧发酵
氨氮
corncob
fowl dung
methane
anaerobic digestion
ammonia
