Papers by Keyword: Enrichment

Abstract: This work presents studies on the material composition and physico-mechanical characteristics of an alumina-containing estimate formed during the production of aluminum on electrolyzers with self-baking anodes during technological operations. The material is a mixture of fine powder 2.5 mm in size (62.78% on average mass) with the presence of pieces of material ranging in size from 0.5 to 6 cm (average 20.26% by weight). The samples contain pieces of hardened aluminum with sizes from 5 to 20 mm (16.96%). The largest content in the sample has the fineness classes-0.315 + 0.16 mm in the volume of 29.85% and the largest class +2.5 mm-37.22%. B It was established that aluminum is concentrated in the fractions-0.315 + 0.16 mm (45.7%) and 0.16 + 0 mm (48.8%), silicon in the fraction-0.63 + 0.315 mm (1.91%), iron at-1.25 + 0.63 mm (0.601%) and-0.63 + 0.315 mm (0.62%). The material consists of cryolite (Na₃AlF₆), chiolite (Al₃F₁₄Na₅), quartz, feldspar, carbonaceous matter and the technogenic phase of the composition (NaF) 1.5CaF₂ AlF₃. The material is characterized as non-abrasive (working index Ai - 0.0184) and very soft in relation to impact crushing (working index CWi - 3.64), the working index of ball grinding Bond (BWi - 6.47) characterizes a very low resistance to ball grinding. The implementation of the crushing operation of an alumina-containing estimate will allow the use of dry cascade-gravity and centrifugal classification to separate impurities in the form of SiO_2, and Fe₂O₃ for the use of alumina-containing material in primary aluminum technology. On the basis of laboratory tests, it is established that alumina-containing raw materials can be separated and photometric and gravitational separation methods can be used. A mathematical model of the motion of particles of primary and prepared alumina-containing raw materials in a cascade-gravity classifier was developed. The criteria and factors characterizing the alumina-containing material, as well as influencing and determining the maximum material enrichment, are established.

Abstract: Indonesia coal ash is predicted to reach 10.8 million tons in the year 2020 but its utilization is still limited. In the last decade, coal ash has become a promising REY source candidate. To determine the potency of REY in Indonesia coal ash, information about element concentration and mineralogy of the ash is essential. In this study, coal ash samples were taken from Paiton-2, Pacitan, Rembang, and Tanjung Jati coal-fired power plants. Element content and mineralogy were analyzed using Inductive Couple Plasma Mass Spectroscopy/Atomic Emission Spectroscopy (ICP-MS/AES), X-Ray Diffractometer (XRD) and petrographic. The results showed that coal fly ash and bottom ash contains critical REY in the range of 38% to 41% with C_outlook larger than one. XRD analysis showed that both fly ash and bottom ash have similar mineral phases with slightly different concentrations. The mineral phase is dominated by amorphous glass, quartz, Fe-bearing minerals, and unburned carbon. The amorphous glass phase in fly ash is in the range of 23 to 34% while in bottom ash between 14 and 34%. Unburned carbon content in fly ash and bottom ashes are 7-13% and 7-19%, respectively. Fe-bearing mineral content in fly ash is 15-20% and bottom ash is 13-20%. In addition, Indonesia coal ash has a higher Heavy-REY enrichment factor than Light-REY. The Enrichment Factor of HREY in fly ash is as much as 1.3 times (in average) of the bottom ash.

Abstract: Rare Earth Element plus Yttrium (REY) is an critical element in green technology and consumer goods. Due to its limited supply, it is necessary to look for alternative sources of REY which one of the potential candidates is coal fly ash. Two samples of coal fly ash which originated from Indonesia were leached in an alkaline solution in order to remove Si and increase REY content. Samples were collected from pulverized coal power plant in East Java (sample T) and West Java (sample I). Leaching conditions were studied including concentration of NaOH, ratio of volume of liquid (L) to weight of solid (S) and leaching time. It was found that the optimum condition was reached at NaOH concentration of 8M, L/S ratio (10 mL: 1 g) and leaching time of 120 min. At this condition, percent removal of Si and REY enrichment were respectively 56.22% and 30% for sample I, and 33.75% and 24% for sample T.

Abstract: The South-Yakut basin is the most promising new field. The coal types of the South Yakut basin belong to the most valuable brand of the steel industry. The main aim of this work was to study the fluoroapatite coal dust of the following stratum-industrial samples of deposits of the South-Yakut basin. The high efficiency and selectivity of the flotation process are considered.

Abstract: Identification and characterization of CTCs can be used as a tool for the study of cancer metastases. A novel design of microfluidic chip used for enrichment of circulating tumor cells is presented in this paper. An integration of DLD method and negative enrichment method were designed to improve the throughput and recovery rate while getting intact CTCs. The DLD stage is used to separate CTCs from blood cells preliminarily, and the negative enrichment stage is used to acquire purified CTCs. Both of them were simulated with COMSOL Multiphysics. Simulation results showed that triangular micro-posts have better performance in DLD stage, and wave structures could generate better disturbance effect than herringbone structures. This chip provides a potential approach with high throughput and purity for the enrichment of CTCs.

Abstract: The characterization of phosphoproteins requires highly specific methods for the separation and enrichment of phosphopeptides. Here we report a novel metal ion-immobilized solid phase material for the separation and enrichment of phosphopeptides. The material is uranyl-salophen-silica gel (USSG) particles in which salophen is a tetradentate ligand of uranyl ion. In USSG salophen is connected on the surface of silica gel and uranyl is bound on the surface through its coordination with salophen. Phosphopeptides can be selectively retained by USSG because uranyl-salophen can bind phosphate moiety with strong affinity and high selectivity. The new material USSG has been successfully used for the separation of phosphopeptides from peptide mixtures with the separation efficiency of 97.0% to 97.4%.

Abstract: In this article the mathematical model of non-stationary hydraulic processes occurring in gas centrifuge cascades for uranium enrichment is described. This model simulates the technological equipment behavior in standard and emergency situations for possible operational and disturbing influences. Also, the algorithm of differential equations system solving for this model is represented.

Abstract: The article describes the structure, architecture, principles of construction and operating modes of the computer software that simulates operators' workplaces of centrifuge uranium enrichment production. We have implemented the networking of computer simulator modules and equipment database. A computer simulator of the isotope separation plant of Siberian Chemical Plant OJSC has been created on the basis of the architecture developed. The main purpose of the simulator is to train the operating personnel for production process control in standard and emergency situations.

Abstract: Due to the large flow, low concentration, low enrichment efficiency, potential safety hazards and the difficulty of comprehensive utilization, it is a big challenge for the development and application of enrichment and separation technology for coal mine ventilation methane (CMVM) at home and abroad. And many countries paid more and more attentions to resolve this problem. In this paper, we comprehensively introduce the research progress in the field of gas enrichment and separation of CMVM, and analyze the related research and application situation. Then, we put forward the enrichment and separation of CMVM in the future development will focus on high efficient adsorbent and adsorption & separation & enrichment technology and equipment, etc. in order to effectively form the system technology of separation & enrichment of CMVM. So we can provide technical support and auxiliary equipment for the domestic related enterprises, and ensure the mine safety and CMVM utilization. The application of CMVM in the laboratory can make mining engineering students learn how to use environmental technology to realize energy saving and emission reduction in coal mine.

Abstract: The approach to solving the problem of processing iron ore raw materials of Tebinbulak titanomagnetite deposit (Uzbekistan) is offered. It can provide high-quality steel products. The two schemes of processing of Tebinbulak ore are shown. The choice between the proposed schemes of the Tebinbulak ore processing: variant of "blast furnace – converter" and variant of "metallization – electric smelting" should be made after thorough analysis based on many factors.