Quantitative research of environmental benefits of recycling lead from obsolete CRT

To investigate the environmental benefits derived from recycling lead from CRT (cathode ray tube), the environmental benefits of two scrap lead flow modes, single flow mode and recycling flow mode, were evaluated respectively from both actual and virtual costs perspectives using the treatment cost method. The pollution and ecological destruction could be divided into mining and emissions, and mixing risks of pollutants from smelting. It was found that the actual and virtual costs for the single flow mode of scrap lead were 329.2 CNY/ton and 1322.56 CNY/t, respectively, with the latter being four times that of the former. Moreover, the pollution control costs for two typical lead recycling processes were studied as well. The actual and virtual treatment costs of scrap lead of pyrometallurgy process were 37.80 CNY/t and 3.73 CNY/t, respectively, while the actual and virtual treatment costs of hydrometallurgy process were 135.10 CNY/t and 15.06 CNY/t, respectively. Comparing the actual and virtual costs for the two processes, the treatment cost of pyrometallurgy process was lower than hyrometallurgy, with the former one having a better environment benefit. However, it is limited by the constant ratio of raw materials, since the percentage of scrap CRT glass and lead concentrate is limited to 1:4. Compared with the single flow mode, the average actual and virtual savings of the two typical pyrometallurgy and hyrometallurgy recycling processes were 242.75 CNY/t and 1313.16 CNY/t, respectively, corresponding to 94.2% of the total cost of the single flow mode. The solid waste management costs of mining, the ecological damage produced by underground mining and the water pollution risks from lead in the building materials rank as the top three costs, which account for 47%, 19% and 17% of the total costs of single flow mode, respectively. ©, 2015, Editorial department of Molecular Catalysis. All right reserved.