Technology Research On Rapid Maturation Of Organic Waste Based On Mechanical Enhancement

Since China fully implemented the garbage classification policy in 2016,the treatment and recycling of food waste generated by garbage classification has become an urgent problem to be solved in the next stage.At present,China has initially formed a pattern of food waste treatment industry combining centralized anaerobic and decentralized aerobic.Among them,the rapid hightemperature aerobic composting technology based on mechanical enhancement is more suitable for small and medium-sized counties,cities,villages,and other scenarios,is currently a hot research topic.However,due to the short development time of technology and insufficient in-depth research,most domestic food waste mechanical enhanced rapid aerobic composting generally has problems such as high energy consumption,low product maturity and poor resource utilization.Based on the above problems,this study intends to guide the development of a new type of rapid aerobic composting reactor for food waste and run it in actual conditions by studying the effects of composting process parameters and process products on the maturity of rapid composting.Achieve three goals: improving fermentation efficiency,reducing compost energy consumption,and improving compost maturity.Provide theoretical and technical support for the development of decentralized aerobic technology in China.This study systematically investigated a large number of mechanically enhanced rapid high-temperature aerobic composting projects in China,and tested the products of some typical projects.The phytotoxic substances that are easily generated and accumulated during the rapid composting process were systematically analyzed and screened.The correlation between seed germination index(GI)and process products such as acetic acid,lactic acid,tartaric acid,succinic acid,ammonium nitrogen,and salt at different concentrations was studied through a single factor experiment.Based on the concentration levels of various process products in the project products,it is preliminarily determined that acetic acid,lactic acid,and ammonia are the key factors affecting the low GI of the project products.Based on this,the physical and chemical properties,plant toxic substances,and maturity of the products under different ventilation methods,different re-mixing methods,and other process conditions were systematically explored.Determined the optimal composting conditions.The theory of subsection and phase separation for microbial aerobic fermentation was proposed for the first time.The research results showed that reasonable aeration and increasing mature materials can accelerate the initial temperature rise of the compost,increase the degradation rate of organic matter,and reduce the accumulation of plant toxic substances such as acetic acid and ammonium nitrogen,thereby shortening the maturity time and improving the maturity level of the compost.The product GI can reach over 70%.Based on the relevant process conditions determined by the study,combined with the theory of microbial aerobic fermentation segmentation-phasing.A multi-stage series reactor structure was proposed,and a rapid aerobic decomposition reactor was designed and developed.Determined key reactor parameters such as effective volume,auxiliary heat demand,aeration and induced air fan flow rate.Based on operational requirements,the control logic of the reactor was determined.Pilot experiments were conducted on actual working conditions for verification,and the results showed that the new reactor was able to reach a high GI level stably.At the same time,the physical and chemical indicators,dominant bacterial populations,and microbial numbers of each reactor bin can better correspond to the levels of aerobic composting at different stages,meeting the reactor design requirements.