Characteristics and CO2 sequestration efficiency of mafic tailings distributed in five regions of China

摘要

The characteristics of mafic tailings in the Donghai,Rizhao,Chicheng,Chaoyang and Chengde regions of China have been researched in this paper.We also assess the carbon sequestration effficiency of these mafic tailings by analysing the chemical and mineral compositions of these samples and their specific surface areas.The results show that there are significant differences in chemical and mineral compositions in five regions.Serpentine and clinochlore are the major minerals in Donghai and Rizhao whereas magnesium amphibole and magnetite are dominated in the Chicheng,Chaoyang and Chengde.The MgO components in Donghai and Rizhao tailings are higher compared with those other regions.There are no significant differences in the specific surface areas of tailings from five regions.The chemical and mineral compositions of Donghai tailings show the greater carbon sequestration efficiency,whereas the specific surface area of Rizhao tailings reveals a better carbon sequestration potential.The carbon sequestration efficiencies of tailings in five regions follow the order of Donghai ＞ Rizhao ＞ Chaoyang ＞Chicheng ＞ Chengde based on a comprehensive assessment.