Research On Mechanism And Device Of Pneumatic Conveying Of Pet Recycled Material

Pneumatic conveying system with simple structure,flexible equipment layout,high degree of automation,was widely used in rubber,coal,food,construction,agriculture,chemical and other fields.The recycled materials generated in PET processing were transported by pneumatic conveying,which had the advantages of small energy loss,high conveying efficiency and no environmental pollution.The mechanism of pneumatic conveying of pet recovery material was described,and the flow pattern of gas-solid two-phase flow in the conveying pipeline was defined;The characteristics of conveying materials,such as the shape and size of materials,the specific surface area of material particles,the real density and bulk density of materials,the fluidity of materials,the adhesion and hygroscopicity of materials,were analyzed;According to the aerodynamic characteristics of the material particles,the force and movement of PET recycling material in the air flow were discussed,as well as the conditions affecting the suspension transportation of PET recycling material.The factors affecting pneumatic conveying,such as conveying airflow velocity,solid-gas ratio and conveying gas volume,were studied.The pneumatic conveying process of PET recycled materials was proposed,and a set of pneumatic conveying device for PET recycled materials conveying was designed.The rotary unloader and Venturi material accelerator were combined to accelerate the feeding and conveying of materials for the whole conveying system,which improved the conveying capacity.The pulse bag filter was used as the gas-solid separation device,and the folded filter cloth was used to increase the filtration area,which not only reduced the occupation volume of the dust collector,but also ensured the standard discharge of the separated gas.The gas phase control equation of gas-solid two-phase flow and the particle motion equation were given;The drag model of discrete phase particles,the gas phase turbulence model and the wear model of conveying elbow were discussed.The working conditions of pneumatic conveying of PET recycled materials were clearly defined.According to different working conditions,geometric models were established established for simulation,and the gas phase velocity change,turbulent kinetic energy change,pressure drop change in the tube,particle motion state and velocity change,and the wear condition of the elbow were obtained.The obtained results were analyzed,and the turbulent kinetic energy change,the pressure drop change,the particle motion state and velocity change,and the wear condition of the elbow were obtained,which determined the optimal bending diameter ratio and the optimal airflow velocity of the pneumatic conveying of PET recycled materials.The research results of this subject can provide a basis for the research and design of pneumatic conveying of similar materials.