摘 要：为了探寻水稻秸秆在无流动水和常温的条件下，厌氧消化制取沼气的产气特性和潜力，用质量分数为6%的NaOH溶液对水稻秸秆进行碱性化学预处理，利用自行设计的室内沼气发酵试验装置，进行批量厌氧消化的试验，研究水稻秸秆、牛粪与凹土共发酵过程中的pH值、产气量、甲烷含量和氢气含量的变化。试验结果表明，实验第四组（水稻秸秆、牛粪与凹土按50: 60: 50配比）的累计产气量最高，为15456 mL；经质量分数为6%的NaOH处理后，凹土、水稻秸秆与牛粪混合发酵过程中，实验组各组的甲烷含量能快速地维持在一个稳定水平，其中，实验第一组（水稻秸秆、牛粪与凹土按60: 60: 60配比）的平均甲烷含量最高，峰值达72.2%；经过对产气量、甲烷、氢气含量等指标，以及对经济等因素的综合考虑，得出水稻秸秆、牛粪与凹土按60: 60: 60配比的厌氧发酵工艺最优。67101

毕业论文关键词：凹土，水稻秸秆，沼气，厌氧发酵

Abstract：In order to explore the rice straw in the absence of flowing water and under the condition of normal temperature, anaerobic fermentation production of methane gas features and potential, using the mass fraction of 6% NaOH solution was carried out on the rice straw alkaline chemical pretreatment, using self-designed biogas fermentation test facility in the house, batch anaerobic digestion experiment was carried out. Experimental apparatus for batch anaerobic digestion by anaerobic fermentation was designed study on the effect of NaOH, pretreatment of rice straw anaerobic fermentation process middle volume, pH value and methane content. The experimental results showed that the accumulative gas production of the fourth experimental group (rice straw, cow dung and concave soil by gave 50: 60: 50 ratio) is highest, that is 15456 mL. Furthermore, the mass fraction of 6% NaOH treatment, rice straw, cow dung and concave soil mixed fermentation process, the experimental group of methane content quickly at a stable level, among them, the first group (rice straw, cow dung and concave soil by 60:60:60 ratio) of the average methane content is the highest, the peak of 72.2%. Finally, according to the gas production and methane, hydrogen content and other indicators, as well as to the comprehensive consideration of economic factors, the anaerobic fermentation technology with rice straw, cow dung and concave soil on 60: 60: 60 was to be optimization.

Keywords：Concave soil, rice straw, biogas, anaerobic fermentation                                       

目  录

1 引言 6

2 材料与方法 6

2.1 试验原材料 6

2.2 接种物 6

2.3 试验装置 6

2.4 试验设计 7

2.5 测定项目与方法 7

3 结果与分析 8

3.1发酵过程中pH值的变化 8

3.2 发酵过程中产气量的变化 8

3.3 发酵过程中甲烷含量的变化 10

3.4 发酵过程中氢气含量的变化 10

结  论 12

参考文献 13

致  谢 14

1 引言

地球上最丰富的可再生资源就是农作物秸秆资源，而沼气，作为一种重要的生物质能，已经成为我国农村能源的重要组成部分。据粗略统计，我国农作物秸秆产量位居世界第一，每年产量大约为6～7亿吨，占总农作物秸秆产量的80%[1-3]，而且以水稻秸秆、玉米和小麦为主。除用于饲料或饲料原料、造纸和造肥还田的秸秆以外，还有能够作为能源物质加以利用[4]的秸秆大约为3.7亿吨。但是由于这些秸秆资源并没有获得有效利用，多数被弃置堆放、露天焚烧，形成了严重的资源浪费和环境污染[5-7]。因为这个，进行以秸秆为原料进行厌氧消化的研究，不仅可以解决因焚烧秸秆造成的环境污染问题，还可以为中国可再生能源发展提供新的路径，缓解中国能源供求紧张的局势。