Study On Waste Refrigerators' Dismantling And Release And Removing Of CFC-11 In Rigid Polyurethane Foams

The CFCs is the main ODS.The discarded amount of our country's waste refrigerators has continued to increase,which has become a widespread concern's issue.At present,the domestic research units have developed to combine China's national conditions with manual dismantling methods,but the release amount of CFCs in the dismantling process and how to deal with,which become the bottleneck of market-oriented research and development technology.Research on the release characteristic of CFCs in the manual dismantling process and the release characteristics and disposal methods of CFCs in PUR after dismantling have the great significance to promote our country's waste refrigerator dismantling and PUR treatment.In this paper,based on comparing home and abroad technology of dismantling refrigerator,and combined with China's national conditions and the research foundation,the cutting method of releasing minimum of CFCs was researched.Through study on the choice of cutting tools,cutting methods,and determination of the blowing agent CFC-11's release amount of cutting waste refrigerator in closed systems and peeling off surface plate,the hand-cutting specific tools and the feasible methods of stripping surface plate were given. After being cut into block PUR,the waste refrigerator can reduce volume,storage and transportation costs.When the PUR was shredded to different particle sizes in the closed system,the release and residual amount of CFC-11,the total amount of CFC-11 in the PUR and the determination of the release amount of CFC-11 with time's change for different particle size show that many recovery and treatment system ignore the release of blowing agent which was adsorbed in polyurethane foam(PUR).Exerting the diffusion model calculates the diffusion coefficient of PUR gains of different particles size,and using diffusion coefficient and diffusion model can estimate each year release total amount of CFC-11 of our country during 2002 and 2026.The mass loss,emitted gas composition and structure change of rigid polyurethane foam(PUR) at different temperature were investigated,and the amount of released blowing agent, CFC-11(CCl₃F) was determined when PUR was heated.At 160℃,PUR particles are not decomposed and the CFC-11 which is adsorbing or wrapping in PUR foam is removed at the highest speed.PUR particles which were through 4mm sieves were heated to 160℃for a certain time,then a certain amount of CFC-11 in the PUR particles was removed,and The amount of CFC-11 in the total heating release gas occupied the high proportion.Based on above research and home and abroad recovery processing of waste refrigerators,a complete set of recovery and treatment process in line with the national conditions of China was put forward.