Research On The Key Technology And Application Of Vertical Aerobic Fermentation Equipment

With the rapid development of China’s economy in recent years,animal husbandry is developing towards the direction of scale,intensification and standardization.Intensive excrement can pollute the soil,water and air,and even directly threaten human health.The most economical and environmental friendly method to deal with the animal manure is aerobic fermentation.The vertical aerobic fermentation equipment can deal with livestock and poultry excrement in large quantities,which has great environmental and economic benefits.The existing vertical fermentation equipment has the problems of unreasonable ventilation and high cost of transmission system.In this paper,the stirring ventilation system and transmission system of fermentation equipment were redesigned and studied in depth.The main contents and research results are as follows:(1)The existing vertical fermentation equipment has the problem of unreasonable ventilation.Considering the different oxygen demands of each layer of materials in the fermentation cylinder,the stirring ventilation system of the equipment is improved.According to the structure size of the designed agitator,the stirring resistance moment is calculated.The fermentation equipment is under the condition of low speed and high torque,so the transmission system needs to be redesigned.(2)The stirred resistance moment calculation model of the fermentation equipment is established,the stirred resistance moment is studied by discrete element method,the error between the simulated stirring resistance moment and the calculated stirring resistance moment is within the allowable range of engineering,which indicates that the dynamic load can be neglected in the calculation of stirring resistance moment under this working condition.In order to enlarge the applicable range of the stirring calculation model,the influence of the stirring blade shape and stirring speed on the stirring resistance moment was investigated,and the model was modified according to the simulation results.(3)The equipment is in the low-speed and high-torque condition,and the end of the designed drive system is the sprocket and chain plate mechanism.The force condition is bad,so it is necessary to check its strength and life according to the actual working condition.The sprocket wheel and chain disk mechanism are simulated dynamically.The finite element software was used to simulate the sprocket wheel and chain disk.The fatigue life of sprocket wheel and chain plate is evaluated,and the fatigue life of the mechanism is 5.6 years,which meets the requirements of the service life of the equipment.(4)The improved equipment was trial-produced,installed and debugged,and the trial production test of organic fertilizer was carried out after the equipment was run and closed.The error between the numerical value of the stirring resistance moment obtained by the experiment and that obtained by the calculation model is 3.9%,which verifies the rationality of the calculation model of the stirring resistance moment.All the indexes of organic fertilizer in trial production can meet the relevant national standards,which indicates that the optimized vertical aerobic fermentation equipment can be well applied to the treatment of livestock manure in large-scale farms.