The granulated copper slag prepared by dry centrifugal granulation process was taken as oxygen carrier, a thermodynamic analysis and an experimental study were conducted for oxygen absorption and release reactions of copper slag. The effects of oxidation temperature, reduction temperature, particle size of copper slag and CaO addition on the phase composition of copper slag were investigated. The results show that the reactions of oxygen absorption and release of iron oxide in copper slag run step by step, and the granulated copper slag particles have certain capacity of oxygen absorption and release. Oxidation and reduction at higher temperature is beneficial to reactions of oxygen absorption and release of iron oxide in copper slag. Copper slag with smaller particle size is beneficial to the oxygen absorption reaction of FeO and Fe₃O₄, and addition of CaO is beneficial to the oxygen release reaction of copper slag.

Electrolytic manganese anode slime (EMAS) was processed by adopting sulfur-based reduction roasting and sulfuric acid leaching to separate manganese and lead therein. The effects of roasting temperature, molar ratio of sulfur to manganese, roasting time, particle size of EMAS, stirring speed in leaching, leaching temperature, leaching time, solid-liquid ratio and sulfuric acid concentration on separation of manganese and lead were studied. The results show that with the optimized roasting conditions, including roasting temperature of 550 ℃, molar ratio of sulfur to manganese at 1∶1, roasting time of 50 min, EMAS at particle size of -0.177 mm, and optimized acid leaching conditions including stirring speed of 350 r/min, leaching temperature of 40 ℃, leaching time of 20 min, solid-liquid ratio at 1∶20, and sulfuric acid concentration of 2.5 mol/L, the leaching rate of manganese from EMAS can reach 97.4%, and the concentration of manganese ions in filtrate is 38.84 g/L, while the content of Pb in leaching residue is 45.26%. As a result, the effective separation between manganese and lead can be actualized.

Aiming at the problems of insufficient dissociation degree of mineral monomer and unsatisfactory indices in the leaching process of roasted gold ore in a smelter of Lingbao Gold Group Co Ltd, an ALC mill, for the first time, was applied to fine grinding of roasted gold ore. The results show that with ALC mill used in an open-circuit fine grinding, the filter cake pulped and then milled to a fineness of -38 μm 96% before cyanide leaching, the final cyanide tailings can have its gold grade reduced from 1.72 g/t to 1.42 g/t. As a result, the comprehensive economic benefit can be increased by 8.156 8 million yuan per year.

Fluorite and barite in a low-grade associated ore are intimately intergrown, with the content of 21.2% and 41.7% respectively. Thus, it is hard to separate them via flotation process as they possess similar floatability. In view of the characteristics of this ore, a closed-circuit preferential flotation process consisting of one stage of roughing and seven stages of cleaning was adopted in an experiment, producing a high-quality fluorite concentrate with a yield of 15.60%, CaF₂ grade of 97.36% and recovery of 70.43%, while the BaSO₄ content therein was reduced to only 0.77%. In flotation process, the synergistic effect between inorganic and organic depressants can strengthen the depression of barite and significantly improve the selectivity of fluorite collector, resulting in an efficient separation of fluorite and barite.

A nine-hole cut blasting method was adopted in a test of Tonglushan stope. In combination with on-site actual situation, cutting blasting with medium hole length was studied by using theories of compensated space and fissure zone. The first circle of blasthole layout for cutting blasting was optimized, and four types of models for first circle of blasthole layout were then established by LS-DYNA software. After simulation calculation, the rock blasting effect was simulated by using RHT constitutive model. The results show that the more number of empty blastholes (that is, the larger the compensation space), the better the blasting effect in cutting area. The uniformity of empty blasthole position (that is the uniformity of compensative space) will also influence blasting effect. It is shown that both the section and height of the trench after blasting in the field test meet the design requirement, which proves that the first circle blasthole layout for cutting blasting is reasonable.

In order to improve accuracy in selection of blasting parameters for open-pit mines, a mathematical model was established for determining bench blasting parameters in open-pit mines based on production cost of stope, and the blasting parameters were then optimized by using an improved sparrow search algorithm. The results show that the improved sparrow search algorithm can effectively improve the effect of bench blasting in open-pit mine, but also improves the construction efficiency. With Yulong Mining Industry Company in Xizang as an example, the blasting parameters after optimization are as follows: hole spacing of 6.2 m, row spacing of 4.9 m, and unit explosive consumption of 0.32 kg/t. With these blasting parameters, the stope production cost goes down by 7.5% to 11.06 yuan/t, and the bulk rate can be controlled within 10%.

To address the problems of low conductivity and poor cycling performance of silicon oxide as negative electrode material, polyacrylamide (PAM) was adopted as a carbon source for the first carbon coating, and the methane-acetylene mixture was used as a gas-phase carbon source for the second coating by chemical vapor deposition to prepare nitrogen-containing double-layer carbon-coated silicon oxide anode materials (SiO_x@ DC-N). Compared with pure gas-phase coated (SiO_x@ GC) and pure liquid-phase coated (SiO_x@ LC) silicon oxide anode material, SiO_x@ DC-N exhibits excellent rate performance and cycling stability, showing that the specific capacity is 850.1 mAh/g at a current density of 4C (1C=1 500 mA/g). The 18650 cylindrical batteries prepared by using a mixed graphite in a ratio of 5∶95 can have a capacity retention rate of 92.70% after 700 cycles of charging and discharging at a current density of 1C.

Effects of Ca²⁺, Mg²⁺, SO₄^2- and PO₄^3- on the flotation behavior and surface properties of dolomite and fluorapatite were studied by performing tests of pure mineral flotation, Zeta potential and contact angle. The results show that dissolved ions can significantly change the floatability, surface electricity property and surface wettability of these two minerals. Ca²⁺, Mg²⁺, SO₄^2- and PO₄^3- can reduce their contact angles, weaken their hydrophobicity and decrease the flotation recovery. Ca²⁺ and Mg²⁺ can increase, while SO₄^2- and PO₄^3- can decrease the Zeta potential of dolomite and fluorapatite. These results can be used as reference for removal of harmful ions in phosphorite ore processing.

In order to improve the working performance of drum cutter in mining mechanism, the cutting process of drum cutter under different working conditions was numerically simulated by using discrete element method (DEM). The effects of cutting thickness, rotating speed and tractor speed on cutting resistance, productivity and specific energy consumption were investigated by single-factor analysis and orthogonal testing. With cutting resistance and specific energy consumption of the drum cutter as evaluation indexes, the best working parameters of the drum cutter were obtained by matrix analysis. The results show that as cutting thickness increases, both cutting resistance and productivity increase, while specific energy consumption decreases. With rotation speed increases, cutting resistance and productivity decrease, but specific energy consumption increases. And with tractor speed increases, both cutting resistance and productivity increase, while specific energy consumption decreases. It is concluded that the optimum working parameters of drum cutter are as follows: cutting thickness of 50 mm, rotation speed of 100 r/min, and tractor speed of 0.06 m/s.

The action and mechanism of copolymer of maleic acid and acrylic acid (PMAA) in flotation separation of barite and fluorite in the presence of collector of sodium oleate were studied. A single mineral flotation test shows that sodium oleate has a good collecting for barite and fluorite, and PMAA has an obvious selective depressing effect on fluorite. A flotation test of artificially mixed minerals confirms that PMAA can achieve the separation of barite from fluorite in the presence of sodium oleate. A Zeta potential test shows that PMAA can hinder the adsorption of sodium oleate on the surface of fluorite, but cannot hinder its adsorption on barite surface. An XPS analysis shows that PMAA isn't effectively adsorbed on the surface of barite, but is chemically adsorbed on the surface of fluorite through the interaction between carboxyl groups of PMAA and calcium ions of fluorite, thus achieving the selective depression of fluorite during the flotation of barite with sodium oleate.