在微波场中合成矿物无机凝胶

以天然矿物为原料,添加其他化学试剂在微波场中合成了矿物无机凝胶,反应时间由常规的6~8h减至45m in,反应温度由230~310℃减至90~95℃。经XRD、DTA、IR和化学成分分析,均表明其特征与天然矿物无机凝胶具有很好的吻合性。     

电缆实体火灾模拟实验与电缆的选用

介绍了电缆（支架明敷、支架穿管明敷、防火桥架内敷设、防火桥架内穿管敷设、穿管埋墙暗敷5种电缆敷设方式）实体火灾模拟实验的结果,分析了不同类型的电缆的选用。鉴于矿物绝缘电缆良好的耐火性能。推荐使用。     

重量法测定油砂中矿物油的含量

介绍了用重量法测定油砂中矿物油含量的方法,并且对测定的两个关键步骤即油砂中油的萃取以及矿物油的分离进行了重点讨论。该方法的加标回收率达到85%左右,结果令人满意。     

A Stokesian dynamics approach for simulation of magnetic particle suspensions

The dynamic behaviour of μm-scale ferromagnetic particles in suspension is of interest for various mineral beneficiation processes. It is, however, difficult to experimentally study such processes at the particle-level. In these instances it can be advantageous to resort to suitable particle simulation methods.Stokesian dynamics is a mesh-free numerical technique developed for suspensions of nm to mm size particles. The method inherently considers hydrodynamic interactions, but additional interaction models can be included depending on the system under investigation. We here present a Stokesian dynamics (SD) implementation, which allows for simulation of the motion of suspended magnetic particles in presence of an external magnetic field. The magnetic interaction model includes particle-field interactions as well as pairwise interactions between magnetised particles.Simulations are compared with experiments using a laboratory-scale flow cell. The method is shown to be realistic for studying ferromagnetic suspensions in mineral processing applications, and can be useful in understanding and predicting the efficiency of mineral separation processes.     

Morphological enhancement of microscopy mineral image using opening‐ and closing‐based toggle operator

To enhance unclear microscopy mineral images, an algorithm based on toggle operator using opening and closing is proposed in this paper. Firstly, the specified toggle operator using opening and closing through designing the selection rules is analysed. Secondly, after importing the multiscale theory into the specified toggle operator, useful mineral image features, especially the mineral details, are extracted using the multiscale theory‐based toggle operator. Finally, the mineral image is enhanced through the strategy of enlarging the contrast between the extracted bright and dark image features. Experimental results on different types of mineral images verified that the proposed algorithm could effectively enhance mineral images and performed better than some other algorithms. The enhanced mineral image is clear and contains rich mineral details, whereas the grey scale distribution of the original mineral image is appropriately maintained. This would be useful for the further mineral analysis. Therefore, the proposed algorithm could be widely used for image‐based mineral applications.     

A process mineralogy approach to geometallurgical model refinement for the Namakwa Sands heavy minerals operations,west coast of South Africa

The original geometallurgical model for the Namakwa Sands deposit was modified to accommodate ore blends in addition to the various single ore types. A process mineralogy approach was followed in a structured and systematic manner to evaluate the integrity of the adjusted model, particularly for ilmenite and zircon, the minerals of highest intrinsic value. This study reproduced recovery relationships predicted by the geometallurgical model for each of the key process functions, and as a result the integrity of the geometallurgical model is validated. Overall, the recovery potential determined for ilmenite and zircon are well adjusted to model estimates. Poor mineral liberation, an anomalously high abundance of garnet and pyroxene and variation in particle chemistry are recognized as the key recovery penalties. The gangue content is the most significant constraint to ilmenite recovery, whereas zircon chemistry is the most important negative factor in the production of a premium quality zircon product. Results of this study contributed to the refinement of the current geometallurgical model and also identified opportunities to optimise mineral resource utilisation in the future.     

Numerical analysis of hydrocyclones with different vortex finder configurations

This paper presents a numerical study of the multiphase flow and performance of hydrocyclone by means of two-fluid model, with special reference to the effects of diameter, length and shape of vortex finder at a wide range of feed solids concentrations. The considered shapes include the conventional cylindrical style and the new conical and inverse conical styles. The simulation results are analysed with respect to cyclone flow and performance in term of cut size d₅₀, water split, Ecart probable E_p and inlet pressure drop. It is shown that when vortex finder diameter or shape varies, a compromised optimum performance can be identified, resulting in relatively small inlet pressure drop, E_p, and water split. Both d₅₀ and E_p are more sensitive to feed solids concentration than inlet pressure drop and water split. Overall, the effect of vortex finder length on the separation efficiency of particles is much less significant than diameter and shape, which shows opposite trends at low and high feed solids concentrations. All these results can be well explained using the predicted tangential and axial velocities and solid volume fraction.     

一种基于八叉树分解的岩矿储量估算方法

论述的基于八叉树分解的岩矿储量估算方法,是针对现有的估算方法普遍存在着对已知数据要求过多、使用繁琐等缺点而提出来的。该方法具有对采样数据的要求不高、使用简便快捷的特点,用在普查阶段的岩矿储量估算有着明显的优越性。     

Laboratory investigation of carbonated BOF slag used as partial replacement of natural aggregate in cement mortars

Direct mineral carbonation produces a material rich in carbonates and with reduced quantities of free oxides. The aim of this work was to show that such materials can be used in the construction domain. Basic Oxygen Furnace (BOF) slag from the steelmaking process has been traditionally seen as unfit for bounded applications due to its propensity to swelling, resulting from hydration of its high free lime content. Here, BOF slag was crushed to suitable particle sizes, carbonated in an aqueous solution of carbonic acid, and utilized to replace 50% of natural sand aggregate in cement mortars. The mechanical and chemical properties of these mortars were compared to mortars containing non-carbonated slags, and a standard cement mortar as a reference. Tests were conducted to determine mortar paste consistency and soundness, and cured mortar compressive strength and leaching tendencies. The results showed a satisfactory performance for all considered aspects (comparable with the reference) of the mortar sample containing 37.5 wt% (1.5 in 4 parts solids) carbonated BOF slag of <0.5 mm particle size.     

Alkaline digestion of dunite for Mg(OH)2 production: An investigation for indirect CO2 sequestration

The sequestration of CO₂ by carbonating natural minerals has a great potential for secure reduction of net CO₂ emissions. Feedstock Mg–silicate minerals are usually converted into Mg rich solutions or Mg(OH)₂ before the carbonation process, due to the slow reaction kinetic of direct carbonation. The present work studied the alkaline digestion of Mg–silicate minerals into Mg(OH)₂ for CO₂ sequestration. Powdered dunite containing ∼73 ± 2 wt% of forsterite (Mg₂SiO₄) was dissolved using highly concentrated NaOH aqueous systems at 90 and 180 °C with varied NaOH concentration and duration of reaction. Thermal analysis and Rietveld Refinement Quantitative Phase Analysis (QPA) confirmed that an effective digestion of dunite was possible at 180 °C achieving 80 wt% of Mg(OH)₂. It was found that NaOH concentration in solution, temperature and duration of reaction significantly influence the progress of digestion.