摘 要:为了提高小麦秸秆的产气量及产气效率,采用Ca(OH)2和NaHSO3对小麦秸秆进行预处理,考察了不同浓度组合预处理对小麦秸秆厌氧消化性能的影响,研究了Ca(OH)2和NaHSO3预处理对小麦秸秆发酵过程中的pH值、产气量和甲烷含量所造成的影响。试验结果表明,4% Ca(OH)2 + 3% NaHSO3预处理下的小麦秸秆的累积产气量为11346 mL,高于其他各处理组;4% Ca(OH)2 + 3% NaHSO3预处理不仅累积产气量最高,甲烷含量也最高,且甲烷含量最高为56.8%;pH开始时波动,15 d后基本稳定。虽然4% Ca(OH)2 + 1% NaHSO3预处理组日产气量以及甲烷含量的峰值均高于4% Ca(OH)2 + 3% NaHSO3预处理组,但是其发酵速度以及甲烷纯度没有4% Ca(OH)2 + 3% NaHSO3预处理组高。由此可得,最佳的工艺条件是4% Ca(OH)2 + 3% NaHSO3 预处理组。70660
毕业论文关键词:氢氧化钙,亚硫酸氢钠,小麦秸秆,沼气,厌氧发酵
Abstract:In order to improve the gas production and gas production efficiency of wheat straw, Ca(OH)2 and NaHSO3 were used for the pretreatment of wheat straw, explore The effects of different concentrations of pretreatment on the anaerobic digestion of wheat straw,study the effects of Ca(OH)2 and NaHSO3 pretreatment on pH value, gas yield and methane content in the fermentation of wheat straw. The test results show that tthe cumulative gas production yield of wheat straw by 4% Ca(OH)2 + 3% NaHSO3 preteatment was 11346 mL, which was higher than other groups; 4% Ca(OH)2 + 3% NaHSO3 preteatment not only has the highest accumulation of gas production, but also the methane content, and the highest methane content is 56.8%. pH value is fluctuated at the beginning, in a steady state after 15 days. Although the daily production and methane content of 4% Ca(OH)2 + 1% NaHSO3 preteatment was higher than 4% Ca(OH)2 + 3% NaHSO3 pretreatment, its fermentation rate as well as the purity of methane is lower than 4% Ca(OH)2 + 3% NaHSO3 pretreatment. It can be seen that the best group is 4% Ca(OH)2 + 3% NaHSO3 pretreatment.
Keywords:Calcium hydroxide, sub-sodium hydrogen nitrate, wheat straw, biogas, anaerobic fermentation
目 录
1 引言 6
2 材料与方法 6
2.1 试验材料 6
2.2 接种物 6
2.3 试验装置与仪器 7
2.4 试验设计 7
2.5 测定项目与方法 8
3 结果与讨论 8
3.1 预处理的pH值变化情况 8
3.2 预处理对日产气量的影响 9
3.3 预处理对累积产气量的影响 9
3.4 预处理对甲烷含量的影响 10
结 论 11
参考文献 12
致 谢 13
1 引言
我国是一个农业大国,农作物秸秆等生物质资源丰富,主要的农作物秸秆有近20种,年产小麦秸秆7亿吨以上,其中有一大半未得到合理的利用[1]。大量的小麦秸秆由于没有科学的处理方法而被丢弃于田间或当场焚烧,造成严重的环境污染,同时也造成资源的极大浪费。利用小麦秸秆制取沼气,不仅可以解决沼气池原料的缺乏问题,为可持续发展寻求了新的路径,也可以从根源上减少秸秆燃烧带来的环境问题。此外,沼液沼渣中含有丰富的氨基酸和微量元素,是良好的饲料和饲料添加剂,还可作为优质有机肥[2]。文献综述