Advanced Materials Research Vols. 753-755

Abstract: It is mainly addressed the relation between the structure and the energy domain using scanning electron microscope (SEM), transmission electron microscopy (TEM) to observe the micro structure. It indicates that some specific micro structures exiting in the Zijin Stone, such as the nanocrystal structure, nanofiber structure, and nanolayer structure, by which the capacities of releasing anion, bactericidal effect can to some extent be explained.

Abstract: Both treatments and leaching tests of an Mg slag sample containing F of 2.15% from an Mg factory in northwest China were conducted in the present study, focusing on problems of F pollutions. By treating at 1000-1200°C in a muffle furnace, F leaching was decreased to a minimum level of 0.49-2.85 mg/l from the Mg slag with an original F leaching of 13.9 mg/l. The F leaching values increased to 4.83-95.5 mg/l, while treating the slag samples in a vacuum furnace. The treatments of Mg slag may thus be carried out in oxidizing atmosphere and under 1200°C to minimize fluorine pollutions and to improve environmental performances of the Pidgeon process.

Abstract: According to the mineralogy of a low-grade Ni-Cu-PGM sulfide ore, a leaching-flotation process was introduced to process the ore. The leaching tests were focused on temperature, acid concentration, and grinding fineness under normal pressure. Results show that most of Mg and Fe can be effectively leached by 25% H₂SO₄ with a small amount of copper and nickel loss in leaching solution. Through separating Fe and Mg in the leaching solution, iron oxide red assaying 75%Fe₂O₃ and light magnesium oxide assaying 95%MgO were obtained. Residue flotation shows that a bulk concentrate assaying 2.72%MgO with a higher PGM recovery can be obtained. The most important fact is that the grade of PGM in the residue gets doubled relative to the raw ore, which enlarges the available low-grade PGM resource in China.

Abstract: Concentration distribution of Nd₂O₃ in 3KA rare earth cell was studied by a self-restraint sample instrumentation of high temperature molten salts. The results were shown that concentration of Nd₂O₃ in this system was less than 4%, and the concentration of Nd₂O₃ decreased from top to bottom on the portrait, but it would be increased a little bit in the bottom point, and the concentration of Nd₂O₃ would be gradually increasing from cathode to anode.

Abstract: The effect of Z-164D dispersant on the grinding efficiency of oolitic hematite was studied. The content of-0.074 mm in the ground product was increased by 30.15% by using Z-164D dispersant which weight was 2% of oolitic hematite compared without using any dispersant under the optimal technological conditions of the grinding aid experiment. It was considered that the content of-0.074 mm in the ground product was increased by 26.52% by using Z-164D dispersant which weight was 1%, so it was confirmed that the weight of Z-164D dispersant was 1% of oolitic hematite from the perspective of economic benefit finally. On this basis, the absorption characteristics of the Z-164D on the oolitic hematite surface which could change the pulp viscosity and the surface experience of particles were studied and the mechanism how Z-164D dispersant improved the grinding efficiency of oolitic hematite was revealed.

Abstract: The alternation of surface properties of orthoclase after biological conditioning with Bacillus mucilaginosus and Aspergillus niger was investigated by zeta potential and adsorption studies. Bioleaching potassium from orthoclase by the two strains were also studied. Results show that IEPs of the two strain continuously decrease in their each logarithmic phase and stable phase. the IEP of orthoclase, after which interaction with cells, moves towords the IEP of cells. The adsorption of B·mucilaginosus is faster and higher than Aspergillus niger onto orthoclase. The potassium extractions by adapted B·mucilaginosus and unadapted B·mucilaginosus reach 24.0% and 18.5% respectively, 23.0% and 20.0% respectively by adapted Aspergillus niger and unadapted Aspergillus niger after bioleaching 9 d.

Abstract: Introduce the basic concepts of the superconducting and superconducting magnetic separation, the species and properties of superconducting material. Through the current use situation of superconducting magnetic separation machine to explain the advantages and disadvantages about superconducting magnetic separation machine than conventional magnetic separation machine. The paper analyzes the main problems of the superconducting magnetic separation. With a clear direction of superconducting magnetic separation research, improve the superconducting magnet of the critical temperature, especially in liquid nitrogen temperature, even at room temperature, which is a very important research subject.

Abstract: Graphite is the very important nonmetallic ore that high and new technology development needs. According to the ore property, a purification technics of some flake graphite was studies. Firstly, the experiment researched the primary grinding fineness condition test, its result showed that grade has good and recovery is more high when coarse grinding fineness-200 mesh is 66.4%. Then on the basic of the test, a closed trial was conducted by five-times-regrinding and six-times-cleaning, the experimental results indicated that the grade of graphite (Fixed carbon content) is 89.48%, recovery rate reached 97.42%, separation index is better. Finally, the analysis of products showed that fixed carbon content of +100 mesh, +200 mesh graphite flake is respectively 92.90% and 90.53%, so we can choose the multi-grade graphite product.

Abstract: To overcome the shorting of inorganic gelatinous such as cement in plugging jobs, MFC-GM plugging agent is developed. MFC-GM is composed of 20% network building material, 70% gelatinous material, 9% activators, and 1% technologic behavior regulator and is used in aqueous slurries with water to cement ratio 1:1.4-1.8. The results of laboratory performance properties evaluation show that the depth of MFC-GM slurries squeezed into sandpack is far less, and the plugging strength of MFC-GM is, about 25MPa, far higher than G grade oilwell cement. This phenomenon is explained in terms of the functions of ingredients and the structure. MFC-GM can be used for plugging perforations and water producing zones, processing following characteristics: plugging radius is less than 0.8m and adjustable; initial setting time in rang 2-6 hours adjustably. MFC-GM plugging agent can meet the needs of unconsolidated sand gas reservoirs and improve plugging effect of gas well water-flooded layer and leakage zone.

Abstract: Focus on the high temperature rheological stability and the fluid loss control of resistance to high temperature drilling fluid system, further determine system formula and the formula of the high temperature drilling fluid system should be optimized. Eventually, a kind of organo-silica drilling fluid system of excellent performance which is resistant to high temperature of 220 degrees has been developed, and the system performances have been evaluated. The high temperature-resistant organo-silica drilling fluid system is of good shale inhibition, lubricity and borehole stability. The fluid loss is low and the filter cake is thin and tight, which can effectively prevent bit balling. The sand-carrying ability is good and the rheological property is easy to control. The performances of drilling fluid remain stable under high salinity and the system can resist the pollution of 6%NaCl and 0.5%CaC1₂. The materials used in this system are non-toxic, non-fluorescent and suitable for deep well drilling.