Solid Fuel Chemistry最新文献

{"title":"Precious Metals in Black Shales of the Baltic Basin (Leningrad Oblast)","authors":"V. I. Vyalov,&nbsp;E. P. Shishov,&nbsp;T. A. Dyu,&nbsp;A. V. Nastavkin","doi":"10.3103/S0361521924700563","DOIUrl":"10.3103/S0361521924700563","url":null,"abstract":"<p>This article presents the results of studies on the noble metal contents of the Paleozoic dictyonema shales of the Baltic sedimentary basin. On the territory of the studied Kaibolovo–Gostilitsy prospecting area, high, up to potentially industrial, concentrations of noble platinum group metals (PGMs), comparable with the concentrations in sedimentary ore types taken into account by the State Balance of Mineral Reserves of the Russian Federation, have been confirmed with a large factual material (more than 600 shale samples). Increased gold and silver contents have also been noted. Palladium predominated in the composition of platinum group metals. The article presents the identified features of the PGM distribution over the area and in the section of the shale-bearing sedimentary strata. Precious metals in the dictyonema shales of the Baltic basin are distributed in the shales in the following forms: in terrigenous scattered finely dispersed native minerals (forms), in impurities in sulfide minerals (mainly in pyrite), and in species localized in the organic matter (Ag and partly Au). The conditions of formation of precious metal mineralization in the dictyonema shales have been reconstructed. The source of precious metals were rocks of the provenance area—the Baltic Shield—and seawater of the ancient sedimentation area, a supplier of a number of rare metals deposited on the geochemical reducing barrier of the dictyonema shales. Increased and stable concentrations of precious metals in combination with large-scale (billions of tons) geological resources of the dictyonema shales indicated the possible presence of a large unconventional mineral resource base of precious metals in the Baltic region of Russia.</p>","PeriodicalId":779,"journal":{"name":"Solid Fuel Chemistry","volume":"59 2","pages":"164 - 173"},"PeriodicalIF":0.8,"publicationDate":"2025-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143740696","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental Investigation on the Influence of Ultrahigh Pressure Cold Briquetting Characteristics with Binders for Pulverized Coal in Hami Area","authors":"Sen Zhang,&nbsp;Haonan Fang,&nbsp;Yiming Gao","doi":"10.3103/S0361521924700526","DOIUrl":"10.3103/S0361521924700526","url":null,"abstract":"<p>Briquetting is a crucial component of clean coal technology. Pulverized coal from Naomao Lake coal mine in Hami area was selected as experimental sample to investigate the effects of binder and moisture content on briquette quality. The results show that binders can enhance relax density, compressive strength, hydrophobicity and durability. And, binder type has a significant impact on energy consumption during briquetting process. For cement and clay, as addition ratio increases, briquetting energy consumption also increases. For bentonite and sodium humate, addition ratio has a small impact on briquetting energy consumption. In addition, compressive strength, hydrophobicity and durability of briquettes gradually increase with the enhancement of moisture content. Moisture can provide effective lubrication during moulding process, reducing friction between raw materials and between raw materials and mold. Afterward, by using the PCA method, a new comprehensive evaluation index was established to investigate the influence of binder type and binder ratio on the quality characteristics of pulverized coal briquetting. The results show that comprehensive evaluation index of briquettes gradually increases with the enhancement of binder ratio, and the briquette containing 15% sodium humate has the highest comprehensive evaluation index, which confirms the reliability of the proposed evaluation method for briquette quality.</p>","PeriodicalId":779,"journal":{"name":"Solid Fuel Chemistry","volume":"59 2","pages":"77 - 87"},"PeriodicalIF":0.8,"publicationDate":"2025-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143740790","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Determination of Gas Contents and Spontaneous Combustion Liabilities of Zonguldak Coals","authors":"Ali Yılmaz,&nbsp;Mehmet Bilen,&nbsp;A. Rasskazova","doi":"10.3103/S0361521924700617","DOIUrl":"10.3103/S0361521924700617","url":null,"abstract":"<p>Gas content and spontaneous combustion susceptibility of coals are among the most important issues to be considered in underground coal mining operations in terms of coal characteristics. Coals may have different gas contents capacities and spontaneous combustion tendencies due to differences in their composition, formation stages and environmental impacts. From this point of view, the gas contents of coals with different spontaneous combustion tendencies should also be examined and these parameters should be evaluated together in terms of preventing possible accidents. As emphasized in the literature studies, the tendency of coal to spontaneous combustion starts with oxygen adsorption to the coal and then combustion starts with the heat released. Within the scope of this study, the gas contents of coal samples taken from the Karadon Region of Zonguldak Hardcoal Basin were determined. In the last stage, the spontaneous combustion susceptibility test was carried out on these samples with the crossing point temperature determination method and their spontaneous combustion susceptibilities (ignition point temperatures and FCC spontaneous combustion index values) were determined. In the light of these findings, spontaneous combustion tendencies and gas contents for Karadon coals were correlated with each other.</p>","PeriodicalId":779,"journal":{"name":"Solid Fuel Chemistry","volume":"59 2","pages":"97 - 103"},"PeriodicalIF":0.8,"publicationDate":"2025-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143740963","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of Different Particle Sizes on Spontaneous Combustion Characteristics of Coal","authors":"Song Wei,&nbsp;Yuqing Wei,&nbsp;Zongxiang Li","doi":"10.3103/S0361521924700496","DOIUrl":"10.3103/S0361521924700496","url":null,"abstract":"<p>Spontaneous combustion of coal is one of the important factors affecting coal mine safety. Many coal mine accidents are caused by spontaneous combustion of coal In order to study the influence of particle size on coal oxidation temperature rise, a temperature programmed test system was used to study the gas generation law in oxidation temperature rise of coal samples with different particle sizes in Dongrong Coal Mine. The thermal reaction of five different particle sizes of coal was studied by differential scanning calorimetry in thermal method The results show that the smaller the particle size, the greater the gas release of coal samples; With the decrease of particle size of coal sample, the reaction area between coal sample and oxygen increases, and the cross point temperature corresponds The particle size of coal sample has obvious influence on the tendency of coal spontaneous combustion. It is of practical significance to study the difficulty of coal spontaneous combustion by using activation energy. According to the experimental data, it is necessary to prevent and control coal mine fires.</p>","PeriodicalId":779,"journal":{"name":"Solid Fuel Chemistry","volume":"59 1","pages":"48 - 52"},"PeriodicalIF":0.8,"publicationDate":"2025-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143513311","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Structure Features of Humic Acids Isolated from Oxidized Kuzbass Coal and Yakutia Brown Coal","authors":"T. M. Solov’ev,&nbsp;G. Shaikhislam,&nbsp;S. A. Epshtein,&nbsp;N. N. Kondrat’ev,&nbsp;S. I. Sivtsev,&nbsp;M. D. Sokolova","doi":"10.3103/S0361521924700447","DOIUrl":"10.3103/S0361521924700447","url":null,"abstract":"<p>The article presents the results of a study of the structure of humic acids isolated from brown coals of Yakutia and oxidized coals of Kuzbass using nuclear magnetic resonance spectroscopy and IR spectroscopy. Based on the ¹³C NMR spectra, their structural parameters, such as the aromaticity index and hydrophobicity index, were calculated. It was noted that the humic acids of oxidized coals were characterized by higher values of the aromaticity and hydrophobicity indices than those of the humic acids of brown coals. The results of titrimetric analysis showed that humic acids isolated from oxidized coals were characterized by a higher concentration of carboxyl and carbonyl groups. Based on the study, it was suggested that the humic acids of brown coals from Yakutia will have stronger growth-stimulating properties than the humic acids of oxidized coals from Kuzbass.</p>","PeriodicalId":779,"journal":{"name":"Solid Fuel Chemistry","volume":"59 1","pages":"1 - 9"},"PeriodicalIF":0.8,"publicationDate":"2025-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143513316","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hydrotreatment of Middle Distillate from Pyrolysis Tar by Using Fixed Bed Reactor","authors":"Janchig Narangerel,&nbsp;Alyeksandr Ariunaa,&nbsp;Oyunchimeg Nasantogtokh,&nbsp;Enkhtur Munkhbat","doi":"10.3103/S0361521924700460","DOIUrl":"10.3103/S0361521924700460","url":null,"abstract":"<p>Hydrotreatment is a crucial operation in the modern oil refining industry, used for removing heteroatoms and hydrogenating aromatic compounds. Middle distillates of coal tar can serve as an alternative feed for producing diesel fuel after heteroatom reduction. Coal tar was obtained through the pyrolysis of Mongolian brown coal at 700°C. The middle distillate, with a boiling range of 220–350°C, was separated from the tar by vacuum distillation, yielding 36.09 wt.%. Hydrotreatment of the middle distillate was carried out at temperatures of 340 and 360°C using a continuous flow, fixed bed reactor filled with a commercial NiMo/Al₂O₃ catalyst. The hydrogen pressure was 6MPa, and the hydrogen flow rate was 0.54 ml/min. The results showed that decreasing the liquid hourly space velocity (LHSV) from 1.55 to 1.03 h^–1 significantly reduced the content of heteroatoms in products from 6.16 to 2.60% and 4.36 to 0.52% for 340 and 360°C, respectively. The total removal of heteroatomic compounds from the middle distillate was highest at 92.36% for the product obtained at 360°C temperature using LHSV 1.03 h^–1.</p>","PeriodicalId":779,"journal":{"name":"Solid Fuel Chemistry","volume":"59 1","pages":"21 - 26"},"PeriodicalIF":0.8,"publicationDate":"2025-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143513314","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Research on the Mechanical Properties and Energy Evolution of Coal Rock under Triaxial Cyclic Gradient Loading","authors":"Minbo Zhang,&nbsp;Shilong Zhang,&nbsp;Chunxin Li,&nbsp;Dangyu Zhang,&nbsp;Cuiling Wang,&nbsp;Yan Jin","doi":"10.3103/S0361521924700459","DOIUrl":"10.3103/S0361521924700459","url":null,"abstract":"<p>With the depletion of shallow coal seam resources, deep mining has become a trend, and deep stress makes coal mining in the process of repeated cyclic loading and unloading. In order to study the energy evolution law of mechanical properties of coal and rock under the action of cyclic gradient loading, the RTX-1000 high temperature and high pressure dynamic rock triaxial loading experiment is carried out on coal samples. The changes of residual strain, elastic modulus, input energy density and dissipated energy density of coal and rock under different cyclic gradient loading are compared and analyzed. The results show that with the increase of confining pressure, the number of cyclic gradients of coal and rock samples increases, and the peak strength increases, which are 16.04, 32.04, and 43.92 MPa, respectively, and the axial, radial and volumetric strains have obvious memorability. In the cyclic gradient loading, the residual variable of the coal sample under the same confining pressure decreases sharply and then slowly, and the graph is concave with the number of cycles. Under the same confining pressure and the cyclic loading gradient, the loading elastic modulus is always higher than the unloading elastic modulus, and the elastic mod-ulus of the coal sample gradually decreases under the same cyclic gradient. In the process of cyclic gradient loading, most of the input energy density is stored in the rock sample in the form of elastic strain energy, and the dissipated energy increases between 0.05 and 0.29% of the total input energy in a single cycle, which provides theoretical guidance for deep coal seam mining and roadway support.</p><p>Highlights</p><p>• The variation law of residual strain and elastic modulus of coal samples under cyclic gradient loading were investigated.</p><p>• The stress peaks of coal samples under different confining pressures were 16.04, 32.04, and 43.92 MPa at 5, 8, and 12 MPa, respectively.</p><p>• The calculation formulas of input energy density, elastic energy density, plastic energy density and dissipated energy density of coal samples were presented.</p><p>• The energy of each part of coal sample under the last cycle gradient was studied with the increase of cycle times, which provides theoretical guidance for deep coal mining and roadway support in reality.</p>","PeriodicalId":779,"journal":{"name":"Solid Fuel Chemistry","volume":"59 1","pages":"10 - 20"},"PeriodicalIF":0.8,"publicationDate":"2025-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143513315","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of Magnesium Ion on Combustion Behavior of Loy Yang Lignite","authors":"Ying Chen,&nbsp;Shixian Fang,&nbsp;Xiangchun Liu,&nbsp;Ping Cui","doi":"10.3103/S0361521924700502","DOIUrl":"10.3103/S0361521924700502","url":null,"abstract":"<p>The effects of Mg²⁺ on the combustion behavior of Loy Yang lignite (LY) were studied. The combustion behaviors of all samples were investigated using a thermogravimetric (TG) analyzer. Moreover, all samples were characterized using Fourier transform infrared (FT-IR) spectrometer with a DRIFT model, scanning electron microscope (SEM), and a specific surface area and porosity analyzer. The results showed that Mg²⁺ was successfully loaded into the acid-washed sample (LYA) in the form of carboxylates. The addition of Mg²⁺ blocked partial pores of LYA. Compared with that of LYA, the peak temperatures of the Mg²⁺ loaded samples (LYA_Mg0.05 and LYA_Mg0.1) decreased by 2.0 and 2.4%, respectively. The activation energies of LYA_Mg0.1 and LYA_Mg0.05 were lower than that of LYA. Overall, Mg²⁺ could catalyze the combustion of lignite. The higher the loading content, the more obvious the catalytic effect is. Additionally, we proposed a mechanism of Mg²⁺ catalyzing the combustion of lignite, i.e., Mg²⁺ acts as an oxygen carrier, which could enhance the transport of oxygen. Consequently, a catalytic effect of Mg²⁺ on lignite burning was observed.</p>","PeriodicalId":779,"journal":{"name":"Solid Fuel Chemistry","volume":"59 1","pages":"53 - 59"},"PeriodicalIF":0.8,"publicationDate":"2025-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143513313","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evolution of Microstructure during Calcination Process and Performance Study of Petroleum Coke","authors":"Xin Zhang,&nbsp;Jiao He,&nbsp;Jingbao Lian,&nbsp;Hongyan Piao,&nbsp;Xin Li","doi":"10.3103/S0361521924700472","DOIUrl":"10.3103/S0361521924700472","url":null,"abstract":"<p>In order to explore the effect of calcination temperature on the microstructure and physicochemical properties of medium and low sulfur petroleum coke, two types of petroleum coke with different sulfur contents were calcined at 600–1400°C. The sulfur content, true density, powder resistivity, Lc value, microstructure and microstructure evolution process of calcined coke were analyzed by DTA-TG-DTG, FT-IR, Raman, polarizing microscope (PLM), FE SEM and other methods. It was found that there is not much difference in the DTA-TG-DTG curves between medium sulfur petroleum coke and low sulfur petroleum coke, and the microstructure evolution process is basically consistent. As the calcination temperature increases, there are significant differences in the growth process and basic properties of carbon crystals in calcined coke, which are closely related to the presence and transformation of sulfur. This study can provide important parameters for the pre-calcined anode desulfurization process in the production of aluminum using medium and low sulfur coke.</p>","PeriodicalId":779,"journal":{"name":"Solid Fuel Chemistry","volume":"59 1","pages":"27 - 37"},"PeriodicalIF":0.8,"publicationDate":"2025-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143513318","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Change in the Distribution of the ‘Three Zones’ of Spontaneous Combustion of Coal in a Coal Mine Goaf with a Retained Roadway by Roof Cutting","authors":"Lin Li,&nbsp;Shufan Zhang,&nbsp;Xiangjun Chen,&nbsp;Zhiqiang Li,&nbsp;Lin Wang,&nbsp;Junwei Yuan","doi":"10.3103/S0361521924700514","DOIUrl":"10.3103/S0361521924700514","url":null,"abstract":"<p>The roof-cutting and pressure-release (RCPR) mining mode can eliminate coal pillar between the adjacent mining faces by automatically forming roadways, which shows the better mining efficiency and economy than the traditional longwall mining mode. However, this mining mode causes changes in the collapse characteristics of the overlying rock and air leakage in a coal mine goaf, which may influence spontaneous combustion of coal in a coal mine goaf. To study the distribution of the spontaneous coal combustion zone in the coal mine goaf under the RCPR mining mode, the distributions of oxygen concentration and temperature in a coal mine goaf are simulated and analyzed after the simulation verification to reveal the new characteristics of the spontaneous coal combustion zone. The research results show that (1) the spontaneous coal oxidation zone is in the type of letter C, different from the one under the traditional longwall mining mode; (2) the air leakage pathway in the type of letter S causes the unique spontaneous coal oxidation zone, which is different from the air leakage pathway in the type of right parenthesis under the traditional longwall mining mode; (3) a temperature index to divide the spontaneous coal combustion zone is determined by the comparison between the temperature distribution and oxygen concentration distribution.</p>","PeriodicalId":779,"journal":{"name":"Solid Fuel Chemistry","volume":"59 1","pages":"60 - 75"},"PeriodicalIF":0.8,"publicationDate":"2025-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143513317","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}