煤中硫和汞赋存形态的同步分析及其相关性研究OA

[Purposes]Sulfur and mercury are two typical pollutant elements with affinity in coal.Clarifying their occurrence forms and correlation of sulfur and mercury in coal is of great significance for the synergistic control of sulfur-and mercury-containing pollutants during coal thermochemical conversion processes.At present,researchers mostly use the national standard method GB/T 215-2003 and sequential chemical extraction method to identify the occurrence forms of sulfur and mercury in coal,respectively,which brings inconvenience to the in-depth analysis of correlation between sul-fur content and mercury content in coal.In addition,it is found that fine-grained pyrite in coal cannot be effectively extracted by HNO3,which means that with the national standard method,the content of pyritic sulfur will be under estimated in coal containing fine-grained pyrite.[Methods]Thereby,a more accurate method was proposed for the simultaneous analysis of occurrence forms of sulfur and mercury in coal-Sequential Chemical Extraction Procedures Combined with Plasma Low-Tempera-ture Ashing(SCEPs-PLTA).Besides,this proposed method was applied to analyze the occurrence forms of sulfur and mercury elements in 40 coal samples with significant differences in sulfur content,mercury content,and pyrite occurrence form.[Results]The research shows that compared with the simple sequential chemical extraction procedures method and the national standard method,SCEPs-PLTA has significant advantages in analyzing the occurrence forms of sulfur and mercury in coal con-taining fine-grained pyrite,and can improve the measurement accuracy of sulfide sulfur and sulfide-bound mercury contents in coal by up to 30.37%and 24.29%,respectively.In addition,sulfur and mercury in coal are mainly in organic(bound)and sulfide(bound)forms(the sum of the two forms ac-counts for more than 40%),and there is a significant positive correlation between the contents of sulfur and mercury in the same occurrence form.[Conclusions]This study lays a theoretical foundation for the migration,transformation,and regulation of sulfur and mercury in coal thermochemical conversion.