蔬菜废弃物厌氧发酵产气特性

Gas Characteristics Generated from Vegetables Wastes by Anaerobic Fermentation

为探究蔬菜废弃物无害化处理效果,以菜花、甘蓝、白菜、西红柿废弃叶与牛粪为原料,在(35±1)℃条件下,利用自行设计的沼气发酵装置,进行单因素厌氧发酵试验,通过测定发酵过程中的产气量、甲烷体积分数、pH等各项指标,对蔬菜废弃物及其与牛粪混合原料厌氧发酵产气规律和特性进行研究。结果表明:菜花叶(A组)、甘蓝叶(B组)、白菜叶(C组)、西红柿叶(D组)单独厌氧发酵会出现两个产气高峰,平均日产气量分别为503.8、584.7、538.3、615.7mL/d,32d的累计产气量分别为16 121、18 709、17 226、19 701mL,其中甘蓝的平均甲烷体积分数最高为50.8%;菜花叶+牛粪(E组)、甘蓝叶+牛粪(F组)、白菜叶+牛粪(G组)、西红柿叶+牛粪(H组)厌氧发酵的平均日产气量分别为1 036.8、699.8、775.2、910.9mL/d,47d的累积产气量分别为48 729、32 891、36 434、42 812mL,其中西红柿废弃茎叶与牛粪混合厌氧发酵的平均甲烷体积分数最高为54.0%。蔬菜废弃茎叶与牛粪混合厌氧发酵呈现发酵周期延长、产气量升高、甲烷体积分数增加的趋势。

For studying harmless treatment effect of vegetable wastes and providing a reliable theoreti cal basis to achieve resource utilization. The current research focus on using cauliflower, cabbage, Chinese cabbage, tomato abandoned stem leaves and cow dung as raw materials of anaerobic fermenta- tion. The temperature of fermentation was 35 ℃ ±1 ℃, the experiment was designed in the rural re- newable energy development and utilization of the west station. In this study we experimented some factors： gas production, methane volume fraction, pH index during the fermentation process, vegeta bles wastes mixing with cow dung as a raw materials of anaerobic fermentation, gas regularity and gas characteristics. The result shows that： cauliflower（group A）, cabbage（group B）, Chinese cabbage （group C）, tomato （group D） abandoned stem leaves single anaerobic fermentation appear two gas peaks, average of daily gas production volume were 503.8, 584.7, 538.3, 615.7 mL/d respectively,and accumulative gas production after 32 days fermentation are 16 121,18 709,17 226,19 701 mk, re- spectively. The highest average of methane volume fraction was cabbage （50. 8%）. The average of daily gas production volume of cauliflower （Group D）, cabbage （Group E）, Chinese cabbage （Group F）, tomato （Group H） stem leaves mixed with cow manure were 1 036.8,699.8,775.2,910.9 mL/d, 47 days respectively, and the cumulative gas production were 48 729, 32 891,36 434,42 812 mLre- spectively. The average methane volume fraction of mixing tomato abandoned stem leaves and cow dung rises up to 54.0%. Anaerobic fermentation of vegetable wastes and cow dung mixed together presents that the fermentation period extended, gas production rate raised and methane volume frac- tion increased.