Design Of Scrap Metal Sorting System Based On Dual Energy X-ray Transmission Technology

With the rapid development of Chinese industry, the renewal speed of automobile, building materials and household appliances accelerates quickly, so the amount of scrap metal is growing quickly. The recycling and reusing technologies of scrap metal resources have become an important research field of the metal industry for sustainable development. The development of scrap metal recycling industry in our country is severely restricted by backward overall level of equipment. In order to improve our technical level of sorting and recycling equipment for scrap metal and the efficiency of metal recycling, dual-energy X-ray transmission sorting technology was researched in this paper.(1) Based on the analysis of dual energy X-ray transmission theory, the R-value curve method and Bayesian decision function for elemental species analysis of metal materials was studied.(2) Based on analysis of dual-energy X-ray transmission signal and its noise, according to the Gauss distribution of detection random noise, irregularities of isolated noise and crosstalk noise between detectors only appears in the fixed channels, a new improved adaptive median filtering method based on the statistic of the neighborhood pixels is proposed, in order to meet the filtering accuracy and rapidity.(3) The control handler of sorting equipment was developed in the Visual Studio 2012. The system includes the control program of X-ray source system, dual-energy linear array X-ray detection system and material conveyor, data acquisition and processing procedures, etc.(4) The overall structure of scrap metal sorting system based on dual energy x-ray transmission technology was designed. The scrap metal sorting system was built with Spellman X-ray source system, Sens-Tech dual-energy linear array X-ray detection system and material conveyor.(5) The filtering method for dual energy X-ray transmission signal was verified by filtering experiment with Aluminum block. Through the analysis of dual energy X ray transmission signal curve and R-Value for copper and aluminum ladder samples, the practical results of the proposed metal material identification method based on dual energy X-ray transmission technology are verified.