微生物异位发酵床技术在北方地区冬季生猪养殖废弃物处理中的应用研究

Research on the application of microbial ectopic fermentation system in pig breeding waste treatment in winter in North China

为了解决我国北方寒冷地区冬季气温低造成微生物异位发酵床"死床"的问题,试验采用在发酵床体内安装热循环系统的方法对传统异位发酵床加以改进,并对冬季发酵床垫料的温度、pH值、含水率、微生物数量和营养成分等理化性质进行测定。结果表明:经改进后的异位发酵床在冬季低温条件下,垫料温度在55~65℃之间保持了7 d左右,发酵产生的高温能够保证发酵垫料的生物安全及卫生;试验过程中发酵床平均pH值稳定在7.6~9.0之间,保证发酵菌群的正常生长;垫料含水率始终维持在45%~60%之间,能够满足发酵床正常运行的需求;发酵过程中细菌数量在试验前期达到峰值(11.5×108 cfu/g)后在2.0×108 cfu/g上下波动,真菌数量达到最大值(19.0×106 cfu/g)后逐渐降至1.2×106 cfu/g,微生物含量变化符合其正常生长规律;发酵后垫料的总氮由2.1%增加至2.6%,碳氮比由23.3下降至16.5,符合国家有机肥的相关标准。说明经改进后的异位发酵床能够在冬季正常运行,可有效解决低温造成的发酵床"死床"问题。

In order to resolve the "dead bed" problem of ectopic microbial fermentation bed caused by low temperature at the cold area in North China in winter, the traditional ectopic microbial fermentation bed was improved by adding heat circulation system into the fermentation bed in this experiment, and the physical and chemical properties of fermentation mattress material in winter such as temperature, pH value, moisture content and microorganism quantity and nutrients were determined. The results showed that the improved ectopic microbial fermentation bed could maintain the temperature of the litter at 55-65 ℃ for about 7 days, the high temperature produced by the fermentation could ensure the organism safety and hygiene of the litter. During the experiment, the average pH of the fermentation bed was stable between 7.6 and 9.0 to ensure the normal growth of the fermentation flora. The moisture content of the litter was maintained between 45% and 60%, which could meet the needs of normal operation of the fermentation bed. During the fermentation process, the number of bacteria reached a peak of 11.5×10~8 cfu/g in the early stage of the test and then maintained a fluctuation at 2.0×10~8 cfu/g, and the number of fungi gradually decreased to 1.2×10~6 cfu/g after reaching the maximum of 19.0×10~6 cfu/g, the change of microbial content was in line with its normal growth pattern. After fermentation, the total nitrogen of the litter increased from 2.1% to 2.6%, and C/N decreased from 23.3 to 16.5, which met the relevant standards of national organic fertilizer. The result indicated that the improved ectopic microbial fermentation could operate normally in winter and could effectively solve the "dead bed" problem of the fermentation.