Study On The Rapid Fermentation Mechanism Of Complex Agricultural And Forestry Wastes

A large amount of agricultural wastes and wastes are produced every year in China.Composting technology is an important means for us to realize the comprehensive treatment of agricultural wastes and wastes.Compared with other traditional composting technologies,membrane composting technology has more obvious advantages,which can reduce the impact of odor on the air,And it can increase the pores in the reactor body,so that the oxygen can contact with the material evenly.In this paper,chicken manure was used as the main material,three kinds of organic waste materials under the agroforestry complex were used as the auxiliary materials,and with the help of membrane composting technology,chicken manure+bacterial residue+litter+chestnut shell,chicken manure+bacterial residue+dead tree branch,chicken manure+bacterial residue were used for mixed fermentation to monitor the changes of many physical and chemical properties in the composting process,and to study the mixed composting effect of chicken manure and different auxiliary materials The integrated online monitoring system and aeration system can realize the rapid composting mode of remote monitoring and control.In the process of experiment,it is found that semi permeable membrane can block the odor and improve the fermentation environment,but with the increase of auxiliary materials,the humification indexes in the same time show differences.Therefore,this paper takes three mixed fermentation modes as the main point to explore the changes of humification process indexes,and proves the rapid and efficient of membrane fermentation through the study of microbial community succession The correlation of environment,physical and chemical factors in the fermentation process,to explore the important factors affecting the fermentation process,put forward the parameter reference system.（1）Through correlation analysis,the water content,t（terminal C/N ratio/initial C/N ratio）,NH₄⁺/NO₃^-,GI and other four indicators were evaluated.The results showed that in the composting cycle,the three kinds of compost were basically in the state of maturity,and the compost No.3 was in the best state of maturity,which may be related to the rich types of compost and the rich microbial flora（2）Based on the composted materials of No.3 pile with the best fermentation effect,high-throughput sequencing technology was used to analyze the bacterial community structure.It was found that Firmicutes and Proteus were the main phyla at phyla level,and Campylobacter,botulinum and Bactria were the main species at genus level.In the early stage of composting,no matter from phyla level or subordinate level,the microbial community structure of compost pile samples was stable It can be seen that the microbial community in the compost pile is rich,and the richness in the late compost stage is higher than that in the early compost stage.In general,the addition of various composting accessories will not affect the succession of microbial community in composting,but may make bacteria more active,composting faster and more efficient.（3）The results showed that the changes of moisture content,p H value,conductivity,ammonium nitrogen,nitrate nitrogen and total organic carbon of three kinds of compost were in accordance with the general fermentation law,and the moisture content and nitrate nitrogen were negatively correlated,while the total nitrogen and nitrate nitrogen were positively correlated.On the basis of 16S RDA analysis,it is found that NO₃^-（32.3%,P=0.004）>TN（12.7%,P=0.08）>C/N（11.8%,P=0.096）.The results showed that during the composting process The content of NO₃^-is an important factor affecting the change of community structure.Nitrate nitrogen is an important factor affecting the change of microbial community.These indicators can be used to evaluate the maturity of compost to a certain extent.