Jinxi Wang

Li Distribution and Mode of Occurrences in Li-Bearing Coal Seam # 6 from the Guanbanwusu Mine, Inner Mongolia, Northern China:

Thirty-six coal bench samples from Coal Seam 6 and 13 parting samples from 5 parting layers were taken from the Guanbanwusu Coal Mine, Jungar Coalfield, Inner Mongolia, and the samples were analysed by optical microscopy, A scanning electron microscope in conjunction with an energy-dispersive X-ray spectrometer (SEM-EDX) analysis, X-ray powder diffraction (XRD), inductively coupled plasma mass spectrometry (ICP-MS) and X-ray fluorescence spectrometric (XRF) techniques. The results indicate that the average Li content are 264 ppm in coal and 1320 ppm or 0.28% Li2O in coal ash, indicating a Li ore deposit in coal. XRD analysis indicates that the minerals are kaolinite, boehmite, chlorite-group mineral, quartz, calcite, pyrite, siderite and amorphous clay material. The absorbed Li phases by kaolinite, boehmite and chlorite could be the most likely host model. Li could also be migrated into the peat by isomorphic impurity in chlorite. However, this migration form should not be the main form because chlorite contents are relative low. The total Li reserves reach to 24288 tons, that is, 52045 ton Li2O in this mine. The Yinshan Oldland chould be the most possible source of Li of the coal. The bauxite of the Benxi formation could be another source of Li of the coal in the NE Jungar Coalfield. The bauxite in the NE Jungar Coalfield was originally derived from the Yinshan Oldland.

Concentrations of Lithium in Chinese Coals

Lithium is an important energy metal. Its concentrations in coals have been studied by many geologists. Its average content is only 14 mg/kg in the coals of the world. Lithium has never been reported as a coal associated deposit before. In order to study the concentrations in Chinese coals, 159 coal and gangue samples were taken from six coal mines and were determined by ICP-MS and the minerals in the samples were identified by X-ray powder diffraction. The results indicate that the Li contents in the coal samples from the Antaibao Coal Mine have reached the industry grade of coal associated deposits. In Tongxing Coal Mine, Li contents in the coal floor rock samples have reached the industry grade of independent lithium deposits. Main minerals are polylithionite, triphylite, zinnwaldite, lithionite and cookeite, which were transported into the peats. Therefore, lithium enriched most likely in the synsedimentary stage in both coal mines. Furthermore, a revised average Li content in Chinese coals was given.

Deformation characteristics of surrounding rock of broken and soft rock roadway

Abstract A similar material model and a numerical simulation were constructed and are described herein. The deformation and failure of surrounding rock of broken and soft roadway are studied by using these models. The deformation of the roof and floor, the relative deformation of the two sides and the deformation of the deep surrounding rock are predicted using the model. Measurements in a working mine are compared to the results of the models. The results show that the surrounding rock shows clear rheological features under high stress conditions. Deformation is unequally distributed across the whole section. The surrounding rock exhibited three deformation stages: displacement caused by stress concentration, rheological displacement after the digging effects had stabilized and displacement caused by supporting pressure of the roadway. Floor heave was serious, accounting for 65% of the total deformation of the roof and floor. Floor heave is the main reason for failure of the surrounding rock. The reasons for deformation of the surrounding rock are discussed based on the similar material and numerical simulations.

Pollution of organic compounds and heavy metals in a coal gangue dump of the Gequan Coal Mine, China

Samples around a coal gangue dump of the Gequan Coal Mine were collected in April 2009. GC (gas chromatography) and GC/MS (gas chromatography/mass spectrometry) were employed to analyze the composition of organic matter in the samples. ICP-MS (inductively coupled plasma mass spectrometry) was used to determine the concentrations of heavy metals. The contents of organic extracts are within the range of 140–750 mg/kg. Alk- and aro-ratios are relatively high. Compared to those of the background sample (GQ13), the contents of saturated hydrocarbon compounds in all the samples are relatively high. The contents of polycyclic aromatic hydrocarbons (PAHs) are relatively high with the distance getting closer to the coal gangue dump. These indicate that organic matter in the samples is from coal particles of the coal gangue dump. The distributions of heavy metals are very similar: the contents decrease with distance from the dump, which indicates that the harmful heavy metals from the coal gangue dump have polluted as thick as at least 500 m.

The smog pollution in Handan - a mining and industrial city in China

Numerous smog events have occurred in recent years in China. Their hazards in mining and industrial cities are more serious than clear days. The samples were collected in the mining and industrial city of Handan. During the smog episode, PM10 and PM2.5 concentrations reach up to 980 μg/m3 and 660 μg/m3, respectively. Under SEM (scanning electron microscope) analysis, the particles consist of soot, fly ash and minerals, which could be from coal mines, power plants, steel mills and auto exhausts. Compared with the samples collected on a clear day, the increased PM10 particles are mainly composed of organic matter, especially aromatic compounds. The Pb content in PM10 of the smog day reaches 507.4 ng/m3 and could be caused by vehicle emissions.

Influences of coal mining water irrigation on the maize losses in the Xingdong Mine area, China.

In 2008, a maize underproduction disaster occurred in the Xianyu village after irrigation using the coal mining water from the Xingdong Mine, China. This disaster resulted in about 40 hectare maize underproduction and 20 hectare total loss of the maize yields. In order to study the reason, a total of 25 soil, water and plant samples were taken from the study area. These samples were analysed by inductively coupled plasma mass spectrometry and ion chromatography. The results indicate that the contents of both water-soluble fluorine and total fluorine are very high and resulting of maize underproduction and total loss of production. The possible pollution sources of fluorine in the study area could be from the coal mine water used for irrigation and glass chemical factory near the study area.

Distribution and Enrichment Mode of Li in the No. 11 Coal Seam from Pingshuo Mining District, Shanxi Province

One hundred and fifteen bench-coal samples were taken from the No. 11 Coal Seam of the Carboniferous in Pingshuo Mining District. These samples were analyzed by ICP-MS, X-ray powder diffraction, SEM–EDX methods. The results indicate that the average Li content reaches 368.84 mg/kg. It is as much as 30 times higher than that of the world coals and 11 times higher than that of Chinese coals. The calculated total Li reserves reach to 259 kt, that is equivalent to, 56 kt Li2O in the No. 11 coal seam in the Pingshuo Mining District. The minerals in the coals are mainly clay, pyrite, and a minor amount of oxide and other minerals. The lithium tends to occur in clay minerals and mainly associated with inertinite maceral. The majority of Li in the No. 11 coal might have migrated from the underlying Yinshan Oldland or bauxite of the Benxi formation by absorption mechanism. The bauxite of the Benxi formation may be the most possible source of Li in the coal from the Pingshuo District.

Organic geochemistry of the Late Permian coals from the Huoshaopu and Jinjia Mines, Liupanshui Coalfield, China

Four coal samples from the Huoshaopu Mine and six coal samples from the Jinjia Mine, Liupanshui Coalfield, China were collected and analyzed, focusing on their petrological and organic geochemical features. The microscopic results show that the vitrinite random reflectance (Ro) of all samples is 0.97%, which is classified as high-volatile A bituminous coal. The maceral groups are dominated by vitrinite followed by inertinite. The low ratios (0.07–0.42) of saturated to aromatic hydrocarbons indicate a terrestrial plant input for the coals. Gas chromatography and gas chromatography/mass spectrometry were employed to analyze the composition of organic matter in the samples. The gas chromatography chromatograms of saturates display a monomodal outline of n-alkanes with a predominance of short chains. The odd-even preference values around 1 reflect the thermal maturity of the coals. Based on the different pristine/phytane ratios and dibenzofuran contents, we infer a relatively weak oxic coal-forming environment for Huoshaopu coals and a relatively anoxic environment for Jinjia coals. Among the aromatics, thermodynamically stable compounds, including 2-methylnaphthalene, 2,6 + 2,7-dimethylnaphthalenes, 3 and 4-methylbiphenyls, 4,4′-dimethylbiphenyl, methylphenanthrene, 2 and 3-methyldibenzofurans, were the dominant isomers in the respective homologs. The occurrence of dibenzothiophenes and benzonaphthothiophenes may confirm the paralic depositional environment of Late Permian coals from the Huoshaopu and Jinjia mines.