The composition of coal-derived light oil (IBP-220℃) was separated into 5 fractions by atmospheric distillation and analyzed by gas chromatography/mass spec- trometry (GC/MS).The light oil was made at 0.1 t/d coal di...The composition of coal-derived light oil (IBP-220℃) was separated into 5 fractions by atmospheric distillation and analyzed by gas chromatography/mass spec- trometry (GC/MS).The light oil was made at 0.1 t/d coal direct liquefaction bench scale unit (BSU) at China Coal Research Institute (CCRI).Six groups of organics,including acyclic hydrocarbon,alicyclic hydrocarbon,aromatics,phenols,polynuclear aromatics and heterocyclics,were found and 80 compounds were tentatively identified in total.Alicyclic hydrocarbon is the main component of the light oil compared to other groups whether in relative mass percentage or the number of compounds in group.The predominant oxy- gen-contained compound is phenols,and the nitrogen-containing compound is pyridine. No sulfur-containing compound is detected.展开更多
To make assessment on its environmental security, fly ash samples were collected from the gangue power plant. Total content of heavy metals in sieved fly ash were analytically determined. We also carried out Tessier e...To make assessment on its environmental security, fly ash samples were collected from the gangue power plant. Total content of heavy metals in sieved fly ash were analytically determined. We also carried out Tessier extractive experiments to check the chemical species of heavy metals. Experiment results show that the content of Cu, Zn, Pb and Cd ascend when particle size is smaller. Cu, Zn, Pb and Cd obviously enrich in particulate fly ash. The chemical species of heavy metal distribution ranking sequence generally is residual〉organic combinative〉Fe-Mn oxide combinative〉carbonate combinative〉ion-exchangeable. Lead＇s amiable-move species were high in proportion, amounted to 35%. Total content of Cadmium is at low level, but its ion-exchangeable species is relatively high in proportion. Nickel and zinc is mainly distributed in residue. Cu is mainly distributed in residue and organic combinative form. The content of manganese is relatively high in fly ash, and the carbonate combinative iron-manganese oxide combinative species are main chemical form. Cr is mainly distributed in residue, and its other chemical species are at low level. Compared with the soil background value of study area and Shandong Province, the content of Cu, Ni, Zn, Mn and Cr in fly ash of gangue power plant is lower. While contents of Pb and Cd were higher than background value, and amiable-move species is relatively high in proportion. They are more apt to cause heavy metal pollution.展开更多
Coal preparation is an integral part of the coal commodity supply chain. This stage of post-mining, pre-utilization beneficiation uses low-cost separation technologies to remove unwanted mineral matter and moisture wh...Coal preparation is an integral part of the coal commodity supply chain. This stage of post-mining, pre-utilization beneficiation uses low-cost separation technologies to remove unwanted mineral matter and moisture which hinder the value of the coal product. Coal preparation plants typically employ several parallel circuits of cleaning and dewatering operations, with each circuit designed to optimally treat a specific size range of coal. Recent innovations in coal preparation have increased the efficiency and capac- ity of individual unit operations while reinforcing the standard parallel cleaning approach. This article, which describes the historical influences and state-of-the-art design for the various coal preparation unit operations, is organized to distinguish between coarse/intermediate coal cleaning and fine/ultrafine coal cleaning. Size reduction, screening, classification, cleaning, dewatering, waste disposal unit operations are particularly highlighted, with a special focus on the LI.S. design philosophy. Notable differences between the U.S. and international operations are described as appropriate.展开更多
As a contributing factor in the dynamic failure(bumping) of coal pillars,a bump-prone coal seam has been described as one that is ‘‘uncleated or poorly cleated,strong...that sustains high stresses."Despite exte...As a contributing factor in the dynamic failure(bumping) of coal pillars,a bump-prone coal seam has been described as one that is ‘‘uncleated or poorly cleated,strong...that sustains high stresses."Despite extensive research regarding engineering controls to help reduce the risk for coal bumps,there is a paucity of research related to the properties of coal itself and how those properties might contribute to the mechanics of failures. Geographic distribution of reportable dynamic failure events reveals a highly localized clustering of incidents despite widespread mining activities. This suggests that unique,contributing geologic characteristics exist within these regions that are less prevalent elsewhere. To investigate a new approach for identifying coal characteristics that might lead to bumping,a principal component analysis(PCA) was performed on 306 coal records from the Pennsylvania State Coal Sample database to determine which characteristics were most closely linked with a positive history of reportable bumping. Selected material properties from the data records for coal samples were chosen as variables for the PCA and included petrographic,elemental,and molecular properties. Results of the PCA suggest a clear correlation between low organic sulfur content and the occurrence of dynamic failure,and a secondary correlation between volatile matter and dynamic failure phenomena. The ratio of volatile matter to sulfur in the samples shows strong correlation with bump-prone regions,with a minimum threshold value of approximately 20,while correlations determined for other petrographic and elemental variables were more ambiguous. Results suggest that the composition of the coal itself is directly linked to how likely a coal is to have experienced a reportable dynamic failure event. These compositional controls are distinct from other previously established engineering and geologic criteria and represent a missing piece to the bump prediction puzzle.展开更多
基金the National Basic Reserch Program of China(2004CB217605)
文摘The composition of coal-derived light oil (IBP-220℃) was separated into 5 fractions by atmospheric distillation and analyzed by gas chromatography/mass spec- trometry (GC/MS).The light oil was made at 0.1 t/d coal direct liquefaction bench scale unit (BSU) at China Coal Research Institute (CCRI).Six groups of organics,including acyclic hydrocarbon,alicyclic hydrocarbon,aromatics,phenols,polynuclear aromatics and heterocyclics,were found and 80 compounds were tentatively identified in total.Alicyclic hydrocarbon is the main component of the light oil compared to other groups whether in relative mass percentage or the number of compounds in group.The predominant oxy- gen-contained compound is phenols,and the nitrogen-containing compound is pyridine. No sulfur-containing compound is detected.
文摘To make assessment on its environmental security, fly ash samples were collected from the gangue power plant. Total content of heavy metals in sieved fly ash were analytically determined. We also carried out Tessier extractive experiments to check the chemical species of heavy metals. Experiment results show that the content of Cu, Zn, Pb and Cd ascend when particle size is smaller. Cu, Zn, Pb and Cd obviously enrich in particulate fly ash. The chemical species of heavy metal distribution ranking sequence generally is residual〉organic combinative〉Fe-Mn oxide combinative〉carbonate combinative〉ion-exchangeable. Lead＇s amiable-move species were high in proportion, amounted to 35%. Total content of Cadmium is at low level, but its ion-exchangeable species is relatively high in proportion. Nickel and zinc is mainly distributed in residue. Cu is mainly distributed in residue and organic combinative form. The content of manganese is relatively high in fly ash, and the carbonate combinative iron-manganese oxide combinative species are main chemical form. Cr is mainly distributed in residue, and its other chemical species are at low level. Compared with the soil background value of study area and Shandong Province, the content of Cu, Ni, Zn, Mn and Cr in fly ash of gangue power plant is lower. While contents of Pb and Cd were higher than background value, and amiable-move species is relatively high in proportion. They are more apt to cause heavy metal pollution.
文摘Coal preparation is an integral part of the coal commodity supply chain. This stage of post-mining, pre-utilization beneficiation uses low-cost separation technologies to remove unwanted mineral matter and moisture which hinder the value of the coal product. Coal preparation plants typically employ several parallel circuits of cleaning and dewatering operations, with each circuit designed to optimally treat a specific size range of coal. Recent innovations in coal preparation have increased the efficiency and capac- ity of individual unit operations while reinforcing the standard parallel cleaning approach. This article, which describes the historical influences and state-of-the-art design for the various coal preparation unit operations, is organized to distinguish between coarse/intermediate coal cleaning and fine/ultrafine coal cleaning. Size reduction, screening, classification, cleaning, dewatering, waste disposal unit operations are particularly highlighted, with a special focus on the LI.S. design philosophy. Notable differences between the U.S. and international operations are described as appropriate.
文摘As a contributing factor in the dynamic failure(bumping) of coal pillars,a bump-prone coal seam has been described as one that is ‘‘uncleated or poorly cleated,strong...that sustains high stresses."Despite extensive research regarding engineering controls to help reduce the risk for coal bumps,there is a paucity of research related to the properties of coal itself and how those properties might contribute to the mechanics of failures. Geographic distribution of reportable dynamic failure events reveals a highly localized clustering of incidents despite widespread mining activities. This suggests that unique,contributing geologic characteristics exist within these regions that are less prevalent elsewhere. To investigate a new approach for identifying coal characteristics that might lead to bumping,a principal component analysis(PCA) was performed on 306 coal records from the Pennsylvania State Coal Sample database to determine which characteristics were most closely linked with a positive history of reportable bumping. Selected material properties from the data records for coal samples were chosen as variables for the PCA and included petrographic,elemental,and molecular properties. Results of the PCA suggest a clear correlation between low organic sulfur content and the occurrence of dynamic failure,and a secondary correlation between volatile matter and dynamic failure phenomena. The ratio of volatile matter to sulfur in the samples shows strong correlation with bump-prone regions,with a minimum threshold value of approximately 20,while correlations determined for other petrographic and elemental variables were more ambiguous. Results suggest that the composition of the coal itself is directly linked to how likely a coal is to have experienced a reportable dynamic failure event. These compositional controls are distinct from other previously established engineering and geologic criteria and represent a missing piece to the bump prediction puzzle.
