Analysis Of The Products For Thermal Treatment Of Waste Electrical And Electronic Equipment

With the rapid growth of WEEE (Waste Electrical and Electronic Equipment) and environmental problems brought about by the increasingly prominent, WEEE recycling and safe disposal has been ever-increasing importance attached. Therefor, Exhibition on WEEE disposal research, ascertain the main types of product for thermal treatment process, there is a great significance for achieving the recycling for WEEE and pollution control.Response to the serious environmental pollution problems of some areas in southern China for WEEE disposal sites, in this paper, through data collection and field research, analysis of more traditional WEEE disposal process, define the typical production process and the key aspects of pollution for civil society to deal with the WEEE such as PCBs (Printed circuit board). On this basis, to scrap waste PCBs, waste wires for the experiment, established the laboratory simulation test program of civil process.Analysis of the thermal treatment of both weightlessness and the main product of the characteristics of the structure of functional groups using the TG-FTIR(Thermo gravimetric Analyzer-Fourier Transform Infrared Spectroscopy) analysis system. The results show that, the pyrolysis process of the waste PCBs has an acutely weight loss stage at 300～400℃, about 20% the samples were lost. The burning process of the waste PCBs has two acutely weight loss stages at 250～520℃, about 40% the samples were lost.The waste computer wires have two smart weight loss stages. The first weight loss stage is at 250～340℃, in which about 45% of the sample were lost. The second weight loss stage is at 420～520℃, in which about 10% of the sample were lost. During the thermal treatment process, first of all, flame retardant heat decomposition occurred, generated halogen compounds and other organic compounds. With increasing temperature, C—C,C—H,C—O chemical bonds of organic polymers breaked, generated alkyl phenol and aromatic compounds.Simulation of the waste PCBs, waste wires were burning and pyrolysis process using tubular furnace experimental system, and analysis of the products of this process using the GC/MS (Gas Chromatography and Mass Spectrometry) and HPLC (High Performance Liquid Chromatography) analysis system. The results show that, The main products of pyrolysis liquid are phenol,isopropyl-phenol and aromatic compounds containing other functional groups, the main products of pyrolysis gases are CO₂ and small molecule alkanes such as propylene, and the solid residue is glass fiber. The main products of burning liquid are phenol,bromo-phenol and isopropyl-phenol, the main products of pyrolysis gases are CO₂,propane,butane and so on. The existence of these organic compounds, is likely to be caused by inadequate combustion. Temperature did not reach the ignition of compounds, products still formed by pyrolysis.The main products of waste wires pyrolysis liquid are organic chloride and aromatic compounds containing one or more benzene rings such as phenol,biphenyl and naphthalene, the main products of pyrolysis gases in addition hydrocarbon and CO , there are organic chlorides such as chloromethane and dichloromethane. At the same time, accompanied by the emergence of a large number of HCl.