Distributed Aerobic Treatment Technolog And Equipment Integration Of Food Waste

With the increase of domestic waste output year by year,the output of food waste as the main component of domestic waste can't be underestimated.If it can't be properly treated,which will pose a huge threat to the environment and people's health.Based on the researched on the output and composition of food waste at home and abroad,combined with my country's vast geographical characteristics and scattered population distribution,this paper formulated a dispersed aerobic treatment route for food waste.After got the key influencing factors of aerobic fermentation in the laboratory,this paper designed and manufactured the aerobic fermentation reactor,and completed the commissioning and operation,and completed the life cycle evaluation and economic evaluation of the technology.First of all,this paper set up a food waste aerobic fermentation treatment platform in the laboratory,made a self-made fermentation device,and explored the effects of fermentation temperature,stirring and ventilation frequency,initial moisture content of materials,bacterial inoculum,fermentation cycle on the fermentation,obtained optimal conditions for aerobic fermentation:fermentation temperature was 45?,stirring and ventilation frequency was 5 minutes,ventilation was 15 minutes,initial moisture content of material was 60 wt%,bacterial inoculation amount was 20%,fermentation period was 14 d,and the degradation rate of organic matter reached 30.72%.Then,according to the optimal conditions of the experiment,this paper designed a 500 kg/d aerobic fermentation reactor with a volume of 1.34 m3 and a single ventilation volume of 5.82 m3.In addition,the heat output during the fermentation process was Qout=245917.61 kJ,and the heat produced during the fermentation process was Qz=212816.61 kJ.After comparison,this paper found that Qz<Qout.Therefore,when the reactor was used for aerobic fermentation of food waste,the heat generated by fermentation it isn't enough to maintain the heat required by the system,and additional auxiliary heating was required.After the design was completed,this paper trial-produced the reaction device and completed debugging and trial operation,which explored the influence of reaction temperature,ventilation conditions,moisture content,material organic matter content and pH on the fermentation effect,and monitored the changes in temperature,moisture content,pH and organic content in the reactor during the fermentation process.The result showed that when the fermentation temperature was set to 45 ?,the ventilation mode was selected at an interval of 5 minutes,ventilation for 15 minutes,the material was dehydrated to 60 wt%by the dehydrator,the bacterial inoculum was 20%,and the fermentation period was 14 days,the fermentation effect was better.The highest degradation rate of organic matter was 31.52%,the highest reduction rate was 87.18%,and all indicators of organic fertilizer produced met the organic fertilizer standard "NY525-2012",which indicated the reaction device had a good adaptability to material handling.Finally,this paper conducted a life cycle assessment and a technical and economic assessment of the project,found that aerobic treatment technology has a lower environmental impact potential than anaerobic treatment technology,it had the greatest impact on global warming,it was mainly caused by CO2 and CH4.If the control of fermentation conditions and the reuse of CO2 could be strengthened,the environmental impact of aerobic treatment of food waste could be greatly reduced.In addition,the economic evaluation showed that the total investment of the project was 1,306,600 yuan,the financial net present value was 648,400 yuan.The result showed that the implementation of the project will bring certain social and economic benefits,and plays a very good role in promoting the development of the environment in a benign direction.