Gas Fat Research Articles

Maceral composition, coal quality and depositional environments of the middle Permian Ukhaakhudag coal deposit, South Mongolia

The Ukhaakhudag coal deposit is located c. 560 km SSE of the city of Ulaanbaatar in the northeastern sector the South Gobi Basin. The coal-bearing strata is part of the middle Permian Tavantolgoi Formation. This study aims to determine the coal petrographic composition and depositional environments of five coal seams in the lower part of the deposit based on petrographic and chemical analyses of 106 composite samples. Vitrinite ranges from 12 to 64 vol.%, and inertinite varies between 9 and 68 vol.%. Liptinite ranges from 1 to 7 vol.%. Microlithotype analyses indicate that coals are primarily vitrinertite, few coals are classified as trimaceralic microlithotypes duroclarite and clarodurite. The inorganic fraction in the studied coals is mainly composed of clay, small amounts of silica, carbonate, and pyrite minerals. The vitrinite random reflectance values of the samples vary between 0.93-1.16 %. Volatile matter content varies from 26.10 to 41.48 wt.% (dry ash free basis). Ash, moisture, and sulfur contents vary between 11.20-44.76 wt.%, 1.63-6.03 wt.% and 0.49-1.67 wt.%, (air dried basis) respectively. Based on random vitrinite reflectance values and volatile matter content, the studied coals are classified as coking (Ch4), fat (Ch5), 1/3 coking (Ch6), gas fat (Ch7) based on the Mongolian system and medium to high volatile bituminous coal when using the ASTM system. The Gelification Index and Tissue Preservation Index of the studied samples suggest most seams accumulated in wet forest swamps with a high tree density. The Middle Permian peats from this location accumulated in mostly alternate oxic and anoxic mire conditions. The climate was drier during the peat accumulation of Seam 0, but it became warmer, and humidity increased starting from Seam 3 accumulation.

Study on 3D spatial characterization analysis and water injection seepage numerical simulation of coal micro-pore/fracture

ABSTRACT To establish a geometrical model to characterize the true microscopic pore and fracture structure of a coal mass and to further study the seepage law of water injection into the coal mass, after three-dimensional X-ray scanning of a coal sample, a three-dimensional reconstruction of the coal sample and a pore network model based on part of the coal sample were generated by means of Avizo three-dimensional visualization software. We conducted a quantitative statistical analysis of the pore numbers, pore throat numbers, coordination numbers and other parameters, and the characteristics of the microporosity connectivity and development degree of the coal were analyzed in depth. ANSYS finite element software was used to simulate the model of water injection seepage under a pressure of 4 MPa. The results show that the pore size distribution of the gas fat coal is irregular: the analyzed sample has a total of 651 pores, a total of 655 pore throats, surface fractal dimensions concentrated at 1.40, and a volume fractal dimension of 2.44. Additionally, 80% of the pore radii range from 0–6 μm, and more than 58% of the pores have coordination numbers of 1–7. Thus, a complex pore topology is observed. Along the water seepage path, the seepage pressure gradually decreases.

СОСТОЯНИЕ СЫРЬЕВОЙ БАЗЫ УГОЛЬНОЙ ПРОМЫШЛЕННОСТИ КУЗБАССА

Analysis of the grade composition of the mineral resource base of the distributed and undistributed subsoil Fund as of 01.01.2018 showed a decrease in reserves of coal intended for open pit mining. In the future, the production of a number of technological grades of coal (gas fat (GZh), fat (Zh), coking fat (KZh), coking (K), coking caking low-metamorphized (KCN), coking caking (KC), lean caking (OC), low caking (CC) is possible only by underground method. The expansion of the raw material base of the Kuzbass coal industry and the support of coal production volumes, primarily by the technological of grades coking fat (KZh), coking (K), coking caking (KC), lean caking (OC), low caking (CC) involves exploration, the use of unconventional production technologies and tax preferences for coal mining enterprise

СОСТОЯНИЕ СЫРЬЕВОЙ БАЗЫ УГОЛЬНОЙ ПРОМЫШЛЕННОСТИ КУЗБАССА

Analysis of the grade composition of the mineral resource base of the distributed and undistributed subsoil Fund as of 01.01.2018 showed a decrease in reserves of coal intended for open pit mining. In the future, the production of a number of technological grades of coal (gas fat (GZh), fat (Zh), coking fat (KZh), coking (K), coking caking low-metamorphized (KCN), coking caking (KC), lean caking (OC), low caking (CC) is possible only by underground method. The expansion of the raw material base of the Kuzbass coal industry and the support of coal production volumes, primarily by the technological of grades coking fat (KZh), coking (K), coking caking (KC), lean caking (OC), low caking (CC) involves exploration, the use of unconventional production technologies and tax preferences for coal mining enterprise

Obtaining Binder for Electrode Paste from Mechanically Activated Coal

It is suggested that the pitch, obtained in the course of coal thermal processing, should be used as binder for manufacturing calcined anodes in aluminum industry. The investigations were carried out to determine the effect of brown and black coal mechanical processing on the degree of its organic matter conversion under thermal autoclave curing in solvent medium. It was established that under temperature of 380°С and pressure of less than 2.0 MPathe yield of the quinoline-soluble fraction of pitch amounts to 80 % for brown coal and up to 92 % for black coal of gas fat rank. It was found that the hydropercussion/cavitation processing of the water-coal suspension within a period of 15 minutes at a frequency of 55Hz increases the degree of conversion of the coal organic matter by 4-6% on average. The index of the coke residue in the pitch obtained from mechanically activated coal also increased by 3-4 %.