预发酵方式对餐厨垃圾酸化抑菌及甲烷发酵的影响  

Effects of pre-fermentation methods on acidification bacteriostasis and methane fermentation of kitchen waste

作　　者：宋娜[1] 汪群慧[1] 王利红[2] 车舜 于淼[1] 赵娜娜[1] 吴川福[1] 

机构地区：[1]北京科技大学环境工程系,北京100083 [2]邯郸职业技术学院建工系,邯郸056001

出　　处：《农业工程学报》2015年第19期240-246,共7页Transactions of the Chinese Society of Agricultural Engineering

基　　金：国家科技支撑计划项目(2014BAC24B01);国家自然科学基金(51278050)

摘　　要：餐厨垃圾水分和有机物含量高,在收集储运过程中易酸腐变臭,影响其资源化利用。该文在新鲜餐厨垃圾中分别接种酵母菌和乙酸菌进行乙醇和乙酸预发酵,预发酵后的餐厨垃圾与酒糟混合进行甲烷发酵,并与不接任何菌种的对照组比较,考察2种预发酵方式对餐厨垃圾酸化抑菌及其与酒糟混合甲烷发酵的影响。研究结果表明,乙酸和乙醇预发酵对餐厨垃圾均具有良好的酸化抑菌效果,其大肠杆菌和金黄葡萄球菌数均比对照组降低了2个数量级以上;累积甲烷产量由高到低的顺序是:乙醇预发酵>对照>乙酸预发酵组,前者累积产甲烷量比对照组和乙酸预发酵组分别提高21.3%和49.8%;乙醇预发酵组乙醇浓度最高,而乙酸和丙酸浓度均最低;相反,乙酸预发酵组挥发性脂肪酸浓度积累导致产甲烷菌活性较低,其产气效率最低。因此,乙醇预发酵是一种既能实现餐厨垃圾酸化抑菌,又能维持发酵系统的稳定性,提高其后续产甲烷效率的有效预发酵方式。Kitchen waste easily sours and smells during the process of collection and transportation because of its high content of water and organic substrate, which hinders its resource utilization. Therefore, how to solve the problem of kitchen waste bacteriostatic preservation is the key to achieve the resource utilization of kitchen waste. The final purpose of anaerobic digestion is to produce methane, so we want to find an effective pretreatment method which can not only realize the kitchen waste bacteriostatic preservation, but also promote the methane production. In this study, fresh kitchen waste was inoculated with yeast and acetic acid bacteria to conduct ethanol and acetic acid pre-fermentation respectively. Ethanol and acetic acid pre-fermentation groups were compared to the control group, which group＇s kitchen waste had no inoculation and just was placed in anaerobic environment. After pre-fermentation, the pretreated kitchen waste was mixed with distillers＇ grains to anaerobic methane fermentation. All groups underwent anaerobic methane fermentation under the same experimental condition. The study was aimed to make clear of the effect of the 2 pre-fermentation methods on acidification bacteriostasis and anaerobic co-digestion compared to the control group by investigating the methane yield, the changes of parameters such as pH value, VFAs（volatile fatty acids）, acetic acid, propanoic acid and ethanol mass concentration during hydrolyticacidification and methane fermentation phase. The results showed that ethanol and acetic acid pre-fermentation performed well on acidification bacteriostasis, as the numbers of Escherichia coli and Staphylococcus aureus both decreased by 2 orders of magnitude during pre-fermentation phase through plate counting method. The descending order for the accumulated methane yield was： ethanol pre-fermentation group（4725 mL） 〉control group（3896 mL） 〉acetic acid pre-fermentation group（3135 mL）, and the accumulated methane yield of ethanol pre-fermentation group

关 键 词：垃圾 发酵 甲烷 乙醇预发酵 乙酸预发酵 酒糟 酸化抑菌 

分 类 号：S216.4[农业科学—农业机械化工程]