摘 要:为了探索水稻秸秆在无流动水和常温的条件下,厌氧发酵制取沼气的产气特性和潜力,分别用质量分数为2%、4%、6%、8%的NaOH溶液对水稻秸秆进行碱性化学预处理,利用生物质能与酶技术重点实验室自行设计的市内沼气发酵试验装置,进行批量厌氧消化的试验,研究NaOH预处理对水稻秸秆厌氧发酵过程中的pH值、产气量和甲烷含量所造成的影响。试验结果表明,4% NaOH 预处理下的水稻秸秆的总产气量为12103 mL,高于2% NaOH处理组和参比组;虽然4%处理组总产气量不是最高,但是其甲烷含量最优,最高为60.8%;pH初期波动,30 d后基本稳定在7.1左右。4% NaOH处理组的VS去除率、TS去除率以及甲烷含量相对于空白参比组和8% NaOH处理组具有显著的差异性(P<0.05),而相对于2%和6% NaOH处理组并不具有显著的差异性(P>0.05),由此可得,较优的工艺条件是4% NaOH预处理组。54252
毕业论文关键词:氢氧化钠,水稻秸秆,沼气,厌氧发酵
Abstract:In order to gas characteristics and to explore the potential of anaerobic fermentation of rice straw for biogas production, without running water and ambient conditions, respectively, NaOH solution for 2%, 4%, 6%, 8% by mass fraction of rice straw by alkaline chemical pretreatment, 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 results show that, the total output of 4% NaOH pretreatment of rice straw is 12103 mL, 73.91% higher than without NaOH; methane content was the highest in more than 60%, and the average methane content is higher than that of no treatment, 2% , 4%and 8% NaOH pretreatment; pH 30 d after initial fluctuations, basically stable at around 7.1. The difference of VS 4% NaOH pretreatment conditions of gas rate, TS rate of gas production and methane content and no treatment and pretreatment of 8% NaOH significantly (P<0.05), and other differences between the two group test was not significant (P>0.05), indicating that the 4% NaOH pretreatment is the optimum technological conditions.
Keywords:Sodium hydroxide (NaOH), 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 7
2.4 试验设计 7
2.5 测定项目与方法 8
3 结果与分析 8
3.1 纤维素、半纤维素和木质素质量百分数的变化 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 9
3.4 发酵过程中氢气含量的变化 10
结 论 11
参考文献 12
致 谢 13
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。据不完全统计,我国每年农作物秸秆产量大约为6~7亿吨,居世界首位,并且以玉米、小麦和水稻秸秆为主,占总农作物秸秆产量的80%[1]。除用于饲料或饲料原料、造纸以及造肥还田的秸秆之外,还有约3.7亿吨秸秆可以作为能源物质加以利用[2]。但是由于这些秸秆资源并没有得到有效利用,大都被弃置堆放、露天焚烧,造成了严重的资源浪费和环境污染[3]。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。 NaOH预处理水稻秸秆厌氧消化产沼气的试验研究:http://www.youerw.com/huaxue/lunwen_58455.html