摘要
为比较秸秆批式发酵和半连续发酵工艺的产沼气效果,以水稻秸秆为单一发酵底物,开展了室内中温批式发酵和半连续发酵对比试验,以容积产气率和原料产气率为特征指标,研究不同料液浓度对秸秆批式和半连续发酵产沼气的影响,以期获得秸秆沼气工程适宜的运行参数。结果表明,批式发酵容积产气率随着TS浓度的增加而增加,但增幅逐渐减少;与静态批式发酵相比,间歇搅拌有助于提高批式发酵容积产气率,特别对高TS浓度处理容积产气率的提升效果更加明显;而半连续进料条件下更有利于高TS浓度处理容积产气率的提高,但各处理原料产气率均随着固物滞留时间(solid retention time,SRT)缩短而逐渐降低。综合考虑产气情况及工程应用实际,建议秸秆批式发酵底物质量分数不超过8%,而半连续发酵TS质量分数8%时SRT设计为20 d(容积产气率1.00 m3/(m3·d)),若发酵TS质量分数6%时,SRT设计为15 d,容积产气率0.75 m3/(m3·d),该运行参数为秸秆沼气工程发展提供了理论依据。
At present, large quantities of straws are burned in field in China, which not only wastes a renewable resource, but also causes serious air pollution. Anaerobic digestion of straws is an alternative method that may produce a clean fuel for energy generation. Currently, more research on impact of digestion for quality content of total solid of manure or mixed materials for the fermentation substrate has been studied, but research is limited in continuous stirred tank reactor for a single type of feedstock. Although the characteristics of anaerobic digestion and properties of gas production at the process of continuous stirred tank reactor and semi- continuous feeding mode has been examined for crushed straw and silage straw as the fermentation substrate, but the operation parameters of such system has not been determined. Thus, in order to obtain the corresponding relationship between solid matter retention time for substrate and the characteristics of gas production, a comparative study to determine biogas production in batch fermentation and semi-continuous fermentation process was carried out under medium temperature conditions with rice straw as feedstock. The effect of quality content of total solid in the batch and continuous biogas fermentation of straws was studied. The volume of gas production rate and the rate of raw material gas production were used as characteristic indicators in order to obtain parameter on optimum quality content of total solid and solid matter retention time for biogas plant with straws. The results showed that fermentation concentration of single straw type used for anaerobic fermentation raw material influenced the gas volume rate under the condition of batch fermentation. With the increase of total solid concentration, the volume of gas production rate was increased in batch fermentation process, but the trend of the increase was gradually decreasing. The volume of gas production rate was improved under condition of intermittent stirred compared with static batch fermentation. Especially, the improving effect was more obvious for the group of high-concentration of TS. However, the volume of gas production rate was more improved for the group of high-concentration of TS under semi-continuous feed conditions, but with the solid matter retention time（SRT） shortened, the rate of raw material gas production with every treatment was gradually decreased. Considering the characteristics of gas production and engineering applications, it was recommended that the concentration of batch fermentation should not exceed 8% for pure straw. For semi-continuous fermentation, if the straw composition in total solids content was 8%, SRT was designed as 20 days（the volume of gas production rate of 1.00 m3/（m3·d））. If the total solids content was 6%, SRT was designed as 15 days（the volume of gas production rate of 0.75 m3/（m3·d）. The operating parameters provided an operational reference for biogas plant only with straw.
出处
《农业工程学报》
EI
CAS
CSCD
北大核心
2015年第15期201-207,共7页
Transactions of the Chinese Society of Agricultural Engineering
基金
国家科技支撑计划(2014BAL02B04)
农业部公益性行业专项(201403019
201503135-17)
江苏省科技支撑计划资助项目(BE2012775)
关键词
秸秆
沼气
发酵
发酵物料浓度
批式
半连续
straw
biogas
fermentation
fermenting substrate concentration
batch fermentation
semi-continuous fermentation
