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Topic Review
Factors Affecting Economic Benefits of Organic-Rich Shale Conversion
On the basis of the verification of various laboratory simulations and field pilot production, academic and industrial circles have agreed on the technical feasibility of shale-oil exploitation after organic-rich shale in situ conversion. However, the kerogen cracking process is an endothermic reaction that needs to consume a certain amount of energy. In addition, during the heating process, inorganic minerals and water in the shale are heated synchronously and consume a significant amount of heat energy. Meanwhile, due to the long heating time, much of the heat energy of shale is also dissipated into the surrounding rock through heat conduction. In addition to the high heating costs, the required equipment for in situ conversion is more expensive. Therefore, many experts and companies are concerned about the economic feasibility of in situ conversion. The economic feasibility of oil shale in situ conversion depends on whether the energy consumption ratio (value of produced oil and gas products/(heating energy consumption cost + engineering costs)) is higher than 1. Only when the value of the produced petroleum products is significantly greater than the cost of heating energy consumption can it be expected to realize economic benefits through large-scale commercial development, the dilution of engineering, and other costs. Therefore, improving the ratio of the value of oil and gas products to the cost of heating energy consumption is very important.
  • 833
  • 16 Jun 2023
Topic Review
Arsenate Minerals
Arsenate minerals usually refer to the naturally occurring orthoarsenates, possessing the (AsO4)3− anion group and, more rarely, other arsenates with anions like AsO3(OH)2− (also written HAsO42−) (example: pharmacolite Ca(AsO3OH).2H2O) or (very rarely) [AsO2(OH)2]− (example: andyrobertsite). Arsenite minerals are much less common. Both the Dana and the Strunz mineral classifications place the arsenates in with the phosphate minerals. Example arsenate minerals include:
  • 799
  • 25 Nov 2022
Topic Review
Sulfosalt Minerals
Sulfosalt minerals are those complex sulfide minerals with the general formula: AmBnSp; where A represents a metal such as copper, lead, silver, iron, and rarely mercury, zinc, vanadium; B usually represents semi-metal such as arsenic, antimony, bismuth, and rarely germanium, or metals like tin and rarely vanadium; and S is sulfur or rarely selenium or/and tellurium. The Strunz classification includes the sulfosalts in a sulfides and sulfosalts superclass. A group which have a similar appearing formulas are the sulfarsenides (for example cobaltite (Co,Fe)AsS). In sulfarsenides the arsenic substitutes for sulfur whereas in the sulfosalts the arsenic substitutes for a metal cation. About 200 sulfosalt minerals are known. Examples include:
  • 770
  • 25 Nov 2022
Topic Review
Mineral-Supported Photocatalysts
Although they are of significant importance for environmental applications, the industrialization of photocatalytic techniques still faces many difficulties, and the most urgent concern is cost control. Natural minerals possess abundant chemical inertia and cost-efficiency, which is suitable for hybridizing with various effective photocatalysts. The use of natural minerals in photocatalytic systems can not only significantly decrease the pure photocatalyst dosage but can also produce a favorable synergistic effect between photocatalyst and mineral substrate. Owing to their unique structures, large surface area, and negatively charged surface, silicate minerals could enhance the adsorption capacity, reduce particle aggregation, and promote photogenerated electron-hole pair separation for hybrid photocatalysts. Moreover, controlling the morphology and structure properties of these materials could have a great influence on their light-harvesting ability and photocatalytic activity. Composed of silica and alumina or magnesia, some silicate minerals possess unique orderly organized porous or layered structures, which are proper templates to modify the photocatalyst framework. The non-silicate minerals (referred to carbonate and carbon-based minerals, sulfate, and sulfide minerals and other special minerals) can function not only as catalyst supports but also as photocatalysts after special modification due to their unique chemical formula and impurities. The dye-sensitized minerals, as another natural mineral application in photocatalysis, are proved to be superior photocatalysts for hydrogen evolution and wastewater treatment. 
  • 749
  • 16 Aug 2022
Topic Review
Primary Rare Earth Elements Resources
Rare earth elements (REEs) are national strategic resources widely applied in industries such as petrochemicals, electronics, national defense and new energy. The primary REE resources are monazite, bastnaesite, xenotime and ion-adsorption type rare earth ore.
  • 691
  • 15 Sep 2023
Topic Review
Respirable Coal Mine Dust Lung Deposition
Respirable Coal Mine Dust (RCMD), with a specific focus on examining particle deposition across different regions of the airway system and lungs. The interplay of several critical factors, including particle characteristics and an individual’s breathing patterns, plays a pivotal role in determining whether particles settle in the lungs or are exhaled. 
  • 684
  • 25 Oct 2023
Topic Review
Knife Handle Working Face
With the rapid development of the social economy, the demand for coal is also increasing. Due to large-scale mining in shallow areas, coal resources are being increasingly depleted. Coal mines are gradually being mined in deep areas. Due to the complexity of coal seam conditions and variability, in order to reduce the loss of coal resources and the amount of moving, and to ensure the efficient mining of mines, the knife handle-type working face came into being. The complex overlying rock structure after the mining of the knife handle-type working face has brought great difficulties to the control of the surrounding rock of the working face.
  • 541
  • 08 Nov 2023
Topic Review
Innovation and Drivers of Productivity
Innovation and technology are important tools for delivering efficiency and productivity improvement in the minerals sector. The uptake of technologies has proven to be an important lever for increasing the productivity of the mining sector.
  • 446
  • 08 Dec 2023
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