Research On Sorting Key Technology And Equipment Of Waste Plastic Film

In recent years, with the increasing number of plastic products, plastic garbage pollution becomes more and more serious, therefore, the recycling of waste plastics are gradually attached attention from people. Abroad, sorting equipment regardless of cost or price is higher, and there exists that sorting plastic kind is onefold, easy to cause environmental pollution and other problems. Our country is still in the relatively backward stage, separation method that primarily with artificial separation. Therefore, according to the present situation of domestic, soft packaging technology for separation of waste plastics are researched and developed, i.e. initially through the winnowing reached preliminary separation purposes, then the use of vibration sieve achieves the waste plastic collection. In this paper, the main research contents are as follows:(1) Analyzing the movement of plastic which in the air chamber and the sieve surface. In the winnowing chamber, broken plastic mixture by its own gravity and wind blowing effect, because the density of different, lighter plastic blown to a distant, while heavier plastic is blown to a nearby, so as to achieve the initial separation effect. It is used a crank slider mechanism as the driving mechanism in the vibrating screen system. After winnowing preliminary separation of plastic mixture, they landed on a vibrating screen, when they suffer its own gravity, and the sieve surface friction and inertia force to slide up and down, because of the plastic components of the total displacement difference are separated. Relevant mathematical models were set up according to the plastic mixture in the winnowing chamber and on the sieve surface force.(2) Related parameters which effect plastic track were optimized analyzed. In the winnowing chamber, the plastic track effect factors have plastic initial velocity, flow velocity and their entrance angle. First, the best combination of values which influenced plastic separation calculated by MATLAB programming, then, the four single factor on plastic track and separation distance effects were researched, each factor adjustment range was derived, parameter adjustment range provide a theoretical basis for practical device in the running process. Because the plastic in the transverse, longitudinal direction movement is independent of each other, so only optimized the plastic on the longitudinal motion, got the optimization value that motor speed and longitudinal direction angle, according to the optimal value and the setting that the separation distance of the target, transverse section angle was calculated.(3) The simulation analysis using CFD software Fluent and motion simulation software Adams. Winnowing indoor flow field was carried out numerical simulation using Fluent, airflow velocity and pressure in the air indoor were simulated and analyzed, a reasonable winnowing chamber structure was designed and the air entrance shape was improved. Screen body model was built in the UG, plastic sheet motion simulation was made after the model was introduced to the Adams. Then we can research and analysis of motor speed effect on the spacing of various plastic separating, inspect and verify correctness of optimal values. It provides a strong theoretical basis for the actual screen body movements in motor speed adjustment.(4) A whole prototype was researched and developed on the basis of theory and simulation analysis. According to the optimized parameters and the structure characteristics of flexible packaging plastic composite separation equipment key parts and structure were designed. In order to meet the actual work of high precision of separation, adjustable structure was designed, it can achieve the convenient purposes that adjustment of winnowing angle, vibration sieve surface transverse and longitudinal direction.This topic research content provide a new design concept for our country waste plastics separation technology, which has important reference value.