| The harmless disposal of dead livestock and poultry plays an important role in ensuring food safety and public health.It can also prevent and control epidemic diseases and promote healthy development of animal husbandry.Composting is a safe and effective way of harmless disposal of dead livestock and poultry.While eliminating pollution,composting can also realize waste recycling.Therefore,based on the research status and development requirements of harmless disposal of dead livestock and poultry,it is of practical value and theoretical significance to develop a composting reactor of dead livestock and poultry which is suitable for China.Through the research and analysis of the key factors of the dead livestock and poultry composting,the theoretical basis for determining the process and structural parameters of the reactor is provided.On this basis,the overall structure of the compost reactor is designed,including the main body of the reactor drum,the spiral blade in the cylinder,the loading door,the inspection door and the material sieve.A support drive system for the reactor is also produced,matching with the rack and cover part.Finite element analysis software is used to check and analyze the key components:sprockets and drive shaft,of the drive system,and optimize the improvement.The simulation experiment of material movement in the drum is analyzed by EDEM discrete element analysis software.According to the test results,the designed parameters are determined,and the selection of standard parts is also carried out.Thus the design and calculation of all non-standard parts and the drawing of the whole processing drawings have been completed.The final main design parameters are:roller diameter:1.2m,drum length:9.1m,dead livestock daily handling capacity:175KG,fermentation period:7～14 days,equipment power:0.75kW.After the prototype test,the EDEM simulation results are verified by using cow dung material with moisture content of 52.2%and bulk density of 549kg/m3.The results show that the drum inclination has the greatest influence on the time and filling rate of the material in the drum,the diameter of the discharge port is the second,and the angle between the blade and the cross section of the drum is the least.The larger the angle of the drum and the diameter of the discharge port is,the shorter the residence time and the lower the filling rate is.When the angle between the blade and the cross section of the drum is 45 degrees,the residence time is the shortest and the filling rate is the lowest,which is consistent with the simulation results.The inclination of the drum impacts the material distribution to the largest extent.When the inclination angle is among 0～3 degrees,the material distribution has the most homogeneous effect.During the whole test,the composting reactor runs smoothly without vibration and noise.The discharging screen works normally,and the working power is reasonable,which meets the design expectation. |
