To promote the rational development and use of clean coal resources in China, data on the regional and age distribution of sulfur, arsenic and other harmful elements in Chinese coal was broadly collected, tested for c...To promote the rational development and use of clean coal resources in China, data on the regional and age distribution of sulfur, arsenic and other harmful elements in Chinese coal was broadly collected, tested for content, and analyzed. Coal in northwestern China is characterized by low to extremely low levels of sulfur; the coal of the Taiyuan Formation in northern China mainly has high-sulfur content; that of the Shanxi Formation is mainly characterized by low sulfur coal; and the Late Permian coal in southern China has overall higher sulfur content; other regions have low sulfur coal. The average content of harmful trace elements in the bulk of China＇s coal is similar to the corresponding content in the coal of the North America and the rest of the world, whereas the content of various elements （Hg, Sb and Se） is different in magnitude to the corresponding percentage in the crust. The average content of the elements Cr, Se, Co, Be, U, Br in Late Permian coal in S China ranks first in the country whereas the average content of Hg and CI in the coals of Late Carboniferous to Early Permian age in N China are the highest. The average content of Mn in Early and Middle Jurassic coal is higher in NW China. The high content of harmful elements in some coal should cause particular concern both in the development and utilization of coal.展开更多
To understand the geochemical characteristics of the No.9 coal in the Daheng Mine of the Ningwu coalfield,the trace element analysis was conducted through X-ray fluorescence spectroscopy(XRF)and inductively coupled pl...To understand the geochemical characteristics of the No.9 coal in the Daheng Mine of the Ningwu coalfield,the trace element analysis was conducted through X-ray fluorescence spectroscopy(XRF)and inductively coupled plasma mass spectrometry(ICP-MS).The sedimentary environment was discussed according to the element geochemical parameters.The results show that Li,Ga,Hf,Zr,Nb,Th,and Ta are slightly enriched in the No.9 coal of Daheng Mine.The average value of the rare earth elements and yttrium(ΣREY)in coal here is 144.20μg/g(excluding parting),which is higher than the average value ofΣREY in the world’s coal and China’s coal.The light rare earth elements(LREY)are enriched.The content of Eu was 0.12‒2.10μg/g with an average of 0.57μg/g,and the Eu is obviously negatively abnormal.Most of the trace elements in the coal are positively correlated with the ash content,which shows that the occurrence of these trace elements is related to inorganic minerals.The results of sequential chemical extraction experiments show that rare earth elements mainly exist in coal in the form of aluminosilicate.The value of the Sr/Ba and the content of S reflect that the coal-forming environment was influenced by seawater.The values of V/Cr and Ni/Co reflect that the peat swamp is in an anaerobic environment and a strongly reducing environment during the coal-forming period.展开更多
INAA (instrumental neutron activation analysis) was used to determine the contents of trace elements in coal samples from 11 workable Permian coal seams in Huainan coalfield. With XRFS (X-ray fluorescence spectrometry...INAA (instrumental neutron activation analysis) was used to determine the contents of trace elements in coal samples from 11 workable Permian coal seams in Huainan coalfield. With XRFS (X-ray fluorescence spectrometry), the geochemical composition of its combustion residues from Tianjiaan Power Plant and Luohe Power Plant was analyzed. In addition, the electron microprobe was employed to study the chemical composition of some fly ashes and bottom ashes. Compared with those of the coals around the world, most trace elements of the Huainan coal are characterized by a normal abundance. Like most coals worldwide, the elements Se, S, As, Sb, Br, U and Cl are enriched in Huainan coal according to dark's value, while the other elements tend to be diluted. The large fluctuation in the contents of trace elements in this kind of coal demonstrates great differences in coal seams. On the other hand, the contents of these elements are very similar in different bottom and fly ash samples. The elements with low organic affinity tend to concentrate in fly and bottom ash than in coal, especially those elements associated with Fe. However, the elements with strong organic affinity tend to be volatile during the combustion. Moreover, the abundance of the elements in fly ash and bottom ash changes with different densities and with different particle sizes. The bottom and fly ashes consist of glass, lime, mullite, coal residues and ferrite minerals. Some residual chars contain higher contents of volatile elements, such as S, P, Cl and As, indicating that the ash containing more residual chars has a strong adsorption of some hazardous elements, suggesting a possible utilization of power plant ash in the field of water cleaning.展开更多
文摘To promote the rational development and use of clean coal resources in China, data on the regional and age distribution of sulfur, arsenic and other harmful elements in Chinese coal was broadly collected, tested for content, and analyzed. Coal in northwestern China is characterized by low to extremely low levels of sulfur; the coal of the Taiyuan Formation in northern China mainly has high-sulfur content; that of the Shanxi Formation is mainly characterized by low sulfur coal; and the Late Permian coal in southern China has overall higher sulfur content; other regions have low sulfur coal. The average content of harmful trace elements in the bulk of China＇s coal is similar to the corresponding content in the coal of the North America and the rest of the world, whereas the content of various elements （Hg, Sb and Se） is different in magnitude to the corresponding percentage in the crust. The average content of the elements Cr, Se, Co, Be, U, Br in Late Permian coal in S China ranks first in the country whereas the average content of Hg and CI in the coals of Late Carboniferous to Early Permian age in N China are the highest. The average content of Mn in Early and Middle Jurassic coal is higher in NW China. The high content of harmful elements in some coal should cause particular concern both in the development and utilization of coal.
基金This research was financially supported by the National Natural Science Foundation of China(41807305,41872173)the Science Foundation of Hebei(E2020209074,D2020402013).
文摘To understand the geochemical characteristics of the No.9 coal in the Daheng Mine of the Ningwu coalfield,the trace element analysis was conducted through X-ray fluorescence spectroscopy(XRF)and inductively coupled plasma mass spectrometry(ICP-MS).The sedimentary environment was discussed according to the element geochemical parameters.The results show that Li,Ga,Hf,Zr,Nb,Th,and Ta are slightly enriched in the No.9 coal of Daheng Mine.The average value of the rare earth elements and yttrium(ΣREY)in coal here is 144.20μg/g(excluding parting),which is higher than the average value ofΣREY in the world’s coal and China’s coal.The light rare earth elements(LREY)are enriched.The content of Eu was 0.12‒2.10μg/g with an average of 0.57μg/g,and the Eu is obviously negatively abnormal.Most of the trace elements in the coal are positively correlated with the ash content,which shows that the occurrence of these trace elements is related to inorganic minerals.The results of sequential chemical extraction experiments show that rare earth elements mainly exist in coal in the form of aluminosilicate.The value of the Sr/Ba and the content of S reflect that the coal-forming environment was influenced by seawater.The values of V/Cr and Ni/Co reflect that the peat swamp is in an anaerobic environment and a strongly reducing environment during the coal-forming period.
基金This paper is supported by the National Natural Science Foundation of China (Nos. 49872054, 40133010 and 49632090) by the "9
文摘INAA (instrumental neutron activation analysis) was used to determine the contents of trace elements in coal samples from 11 workable Permian coal seams in Huainan coalfield. With XRFS (X-ray fluorescence spectrometry), the geochemical composition of its combustion residues from Tianjiaan Power Plant and Luohe Power Plant was analyzed. In addition, the electron microprobe was employed to study the chemical composition of some fly ashes and bottom ashes. Compared with those of the coals around the world, most trace elements of the Huainan coal are characterized by a normal abundance. Like most coals worldwide, the elements Se, S, As, Sb, Br, U and Cl are enriched in Huainan coal according to dark's value, while the other elements tend to be diluted. The large fluctuation in the contents of trace elements in this kind of coal demonstrates great differences in coal seams. On the other hand, the contents of these elements are very similar in different bottom and fly ash samples. The elements with low organic affinity tend to concentrate in fly and bottom ash than in coal, especially those elements associated with Fe. However, the elements with strong organic affinity tend to be volatile during the combustion. Moreover, the abundance of the elements in fly ash and bottom ash changes with different densities and with different particle sizes. The bottom and fly ashes consist of glass, lime, mullite, coal residues and ferrite minerals. Some residual chars contain higher contents of volatile elements, such as S, P, Cl and As, indicating that the ash containing more residual chars has a strong adsorption of some hazardous elements, suggesting a possible utilization of power plant ash in the field of water cleaning.
