大温差地区牛粪高温发酵回用牛床垫料研究

发布时间：2018-04-25 18:38

本文选题：牛粪 + 高温发酵　；参考：《内蒙古工业大学》2017年硕士论文

【摘要】：随着我国经济的快速发展和人民生活水平的日益提高,动物性食品占饮食结构的比重越来越大,养殖业朝着规模化发展。畜禽养殖业在为人民生活水平提高作出贡献的同时,大量的畜禽养殖废物也给环境带来了严重的污染。畜禽粪便的无害化资源化能源化的处理与处置势在必行。牛粪发酵回用垫料技术不仅可以实现养殖粪便就地资源化,同时也不会对环境造成二次污染,为企业较大幅度节约养殖成本,成为养殖业与环境保护协调发展的有效途径之一。但在较为寒冷的大温差地区牛粪高温发酵面临着升温慢、周期长以及发酵难以进行等问题。本研究以发酵温度、发酵含水率、pH值、微生物群落结构以及致病菌等指标作为牛粪高温发酵无害化的标准,研究一年中不同季节发酵情况。结果表明,春季与夏季发酵过程可在自然条件下顺利经历升温期、高温期,结束时含水率接近50%,发酵周期分别为16天和12天,高温期持续时间分别为9天和10天;秋天与冬天未达到高温期,表明低环境温度(-20-15oC)对发酵升温影响较大。考察-10-15oC的亚低温条件下牛粪高温发酵工艺参数的调控过程,优化不同的秸秆添加比例、不同翻抛频率以及不同微生物菌剂原液添加量,结果表明,只有牛粪:秸秆为2:1(体积比)时,发酵体达到高温期且持续7天,其他添加比例则未进入高温期完成发酵过程;翻抛频率4 d/次为最适,不仅升温速度快高温期持续时间长,发酵结束含水率亦最低;添加微生物菌剂原液能明显提高发酵效率完成高温发酵,其中添加1.3 L/t时,进入高温期时间早且持续时间长,发酵完成更彻底。获得了亚低温条件最优发酵工艺,有效加快升温并缩短发酵周期。通过PCR-DGGE研究发酵不同周期微生物群落变化规律,发现夏季快速发酵的微生物群落丰富,尤其在升温和高温阶段,微生物多样性指数高,优势菌群为Clostridium、Bacillus以及Flavobacterium。对整个发酵周期进行PCR荧光定量检测致病菌,结果发现,沙门氏菌和志贺氏菌存在于发酵初期和升温期,高温期和结束时未检出;金黄色葡萄球菌全程未检出;致病性大肠杆菌直至高温期仍然存在,但发酵结束时未检出。由此得出牛粪高温发酵回用牛床垫料工艺满足无害化以及卫生标准,发酵产品可回用于牛床垫料。
[Abstract]:With the rapid development of Chinese economy and the improvement of people's living standard, the proportion of animal food in the diet structure is increasing, and the aquaculture industry is developing in a large scale. Livestock farming contributes to the improvement of people's living standards, and a large amount of livestock and poultry wastes also bring serious pollution to the environment. It is imperative to deal with and dispose of the harmless resources of livestock and poultry dung. The technology of cow dung fermentation and reuse can not only realize the local utilization of aquaculture manure, but also can not cause secondary pollution to the environment. It is one of the effective ways for enterprises to save the cost of culture and to coordinate the development of aquaculture and environmental protection. However, the high temperature fermentation of cow dung in the colder region is faced with the problems of slow heating, long period and difficult fermentation. In this study, fermentation temperature, fermentation moisture content, pH value, microbial community structure and pathogenic bacteria were used as the criteria for high temperature fermentation of cow dung, and the fermentation conditions in different seasons of the year were studied. The results showed that the fermentation process in spring and summer could go through the heating period, the high temperature period, and the water content at the end of the fermentation, the fermentation period was 16 days and 12 days, and the high temperature period lasted 9 days and 10 days, respectively. Autumn and winter did not reach the high temperature period, indicating that the low ambient temperature (-20-15oC) had a great effect on the fermentation temperature. Under the condition of -10-15oC, the process of controlling the technological parameters of high-temperature fermentation of cow dung was investigated, and the different proportion of straw, the frequency of turning over and throwing and the amount of the original liquid of microbial agent were optimized. The results showed that: 1. Only cow dung: when the straw is 2: 1 (volume ratio), the fermentation body reaches the high temperature period and lasts for 7 days, the other adding proportion does not enter the high temperature period to complete the fermentation process, and the optimal throwing frequency is 4 days / times, not only the heating speed is fast and the high temperature period is long, The water content at the end of fermentation was also the lowest, and the fermentation efficiency could be improved obviously by adding the original liquid of microbial bacteria. When 1.3 L / t was added, the time of entering the high temperature period was early and the duration was long, and the fermentation was completed more thoroughly. The optimum fermentation process under mild and low temperature conditions was obtained, which effectively accelerated the temperature rise and shortened the fermentation period. The variation of microbial communities in different periods of fermentation was studied by PCR-DGGE. It was found that the rapid fermentation in summer was rich in microbial communities, especially in the heating and high temperature stages, the microbial diversity index was high, and the dominant bacteria groups were Clostridium Bacillus and Flavobacterium. The results showed that Salmonella and Shigella were not detected at the initial and temperature stages of fermentation, but not at the high temperature and at the end of the fermentation period, but Staphylococcus aureus was not detected in the whole process. Pathogenic Escherichia coli still exists at high temperature, but it is not detected at the end of fermentation. It is concluded that the high temperature fermentation of cow dung can meet the standards of innocuity and hygiene, and the fermentation product can be reused in cattle mattresses.
【学位授予单位】：内蒙古工业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：S823;X713

【参考文献】