Design And Experiment Of Injection Separation Device Of Near Infrared Plastics Sorting System

The wide application of plastic products has produced a large number of waste plastics,which has caused huge pollution to soil,ocean and groundwater.However,waste plastics have huge potential for utilization,at present,the technology and scale of their efficient recycling are still slightly inadequate.There are many kinds of plastics and different properties.Therefore,the most important prerequisite for efficient recycling of waste plastics is to classify and sort mixed plastics.The identification technology based on near infrared spectroscopy(NIRS)has the characteristics of fast,continuous and accurate.Recently,it has gradually become a research hotspot in the sorting industry.The near infrared sorting system for plastics is mainly composed of identification,control and separation devices.The separation device belongs to the executing mechanism,and its function is to receive the controller signal and perform the injection function to realize the separation of the materials.However,because the research direction of sorting equipment often focuses on the improvement of the identification device and control system,the injection and separation device has not been fully optimized.The defects of high energy consumption,large gas consumption,inaccurate injection and large noise limit the efficiency and accuracy of the NIR sorting equipment.In this regard,this topic will focus on the optimization design of the separation device,and comprehensively study the parameters of the injection separation device.In view of the most important component of the jet separation device,the jet nozzle array,the main factors affecting the injection effect are explored.First,through the contrast of different shape nozzles,a circular section streamlined nozzle based on the Vitozinsky curve is proposed.With the help of the CFD tool,the effects of each factor on the jet velocity,the length of the high speed core and the gas consumption are obtained through detailed theoretical analysis,model establishment and initial parameter calculation.By using the orthogonal test,the relationship between the influence intensity of various factors of structure and fluid on the jet is obtained.On this basis,a set of nozzle design parameters suitable for the separation device are obtained.The reliability of the simulation results is verified by the experiment,and the design of the upper injection and blowing separation device of the separation equipment is improved,and the multi function sorting idea is put forward.At present,a detailed comparison is made between the rectangular array nozzles on the separation equipment and the optimized circular section streamlined nozzle.Finally,it is believed that the lower cost of the rectangular nozzle is the cause of its common use,but the streamline nozzle has the advantages of gas consumption,precision and noise in the separation precision and efficiency.It has obvious advantages and has more advantages over the long term.Through the comprehensive analysis of theoretical analysis,CFD simulation and experiment,this project will provide ideas and methods for the research of the injection and separation equipment,reduce the cost of research and development and use,and improve the separation and separation precision of the separation equipment effectively,and promote the popularization and application of the plastics near infrared sorting equipment.