Based on the analysis of ore dilution in Barun mine, the dilution rate at the junction of ore and rock in Barun open-pit mine was controlled. With the actual production into consideration, some controlling measures are put forward for the mine, including accurately identifying ore-rock boundary by drilling and sampling, separating ore and rock by blasting, accurately identifying the ore-rock boundary in muck-pile by blasting, and optimizing shovel loading operation among others. As a result, less waste rock has been mixed with ore, leading to the ore dilution down to below 2%. It is shown that the rate of extraction can be obviously improved.

The effects of brightening agent, such as polysodium dithiodipropanesulfonate (SPS) and sodium 3-mercapto-1-propanesulfonate (MPS), on electrodeposition of Cu from electrolyte with Cu²⁺, H₂SO₄, Cl^- concentration of 85 g/L, 100 g/L and 20 mg/L respectively were studied by adopting linear scanning voltammetry and cyclic voltammetric stripping (CVS), and the effects of SPS and MPS on the tensile strength, elongation, glossiness and roughness of electrolytic copper foil for Li-ion batteries were discussed. The results show that SPS and MPS can promote copper electrodeposition, and also SPS is better than MPS in promotion. However, the compounding with collagen and hydroxyethylcellulose will result in less promotion of copper electrodeposition. In addition, SPS is conducive to improving the tensile strength of copper foil, and MPS is conducive to improving the elongation of copper foil. With concentration of SPS and MPS at 1 mg/L and 1.5 mg/L respectively, the prepared copper foil has flat and dense surface, with better glossiness and roughness.

The lifting of polymetallic nodules was simulated by using a CFD-DEM coupling approach, and the influence of different swirling flow on hydraulic lifting of polymetallic nodules in vertical pipelines was explored. The results show that as swirl ratio increases, the intensity of swirl will be enhanced significantly, and both the maximum fluid velocity and the average axial velocity of particle group will increase. It is found that intensity of swirl can bring obvious impact to the distribution of particles with different velocity in the pipe, showing that particles with high velocity are gradually distributed around the pipe wall, while the particles with low velocity in the center of the pipe. Swirling flow can reduce the local concentration of particles, which is beneficial to reducing the risk of pipeline blockage due to higher concentration of particles caused by retention effect.

In order to avoid formation of material ring in a rotary kiln caused by kiln phosphoric acid process, a technique of high-temperature consolidation of pellets was proposed, and the effects of types of binder, temperature and time of consolidation on the strength and reducibility of phosphate ore pellets were investigated. The results show that consolidation at a temperature over 800 ℃ with bentonite as binder can lead to the pellets with compressive strength and drop numbers obviously higher than those with sodium humate as the binder. With an addition of carbon at 1.4 times of the theoretical amount, CaO and SiO₂ at a molar ratio of 0.35, an addition of bentonite at an amount of 1.5% of the total material weight, consolidation at 1 000 ℃ for 30 min results in the produced pellets with compressive strength of 345.36 N and drop numbers of 33.50.

Beneficiation tests were conducted to process the low-grade cobalt-nickel ore from Hebei Province by adopting an asynchronous flotation flowsheet consisting sequentially of staged grinding, flotation of sulfide minerals and flotation of sulfurized oxide minerals. In the study, combined depressants were used for better depressing of slime, while regrinding process was introduced to intensify the sulfurization effect. Finally, a cobalt-nickel sulfide concentrate with Co grade of 2.00% and Ni grade of 3.90% and a cobalt-nickel oxide concentrate with Co grade of 1.47% and Ni grade of 2.73% were obtained. The total Co recovery and total Ni recovery reached 77.61% and 79.20%, respectively. In this way, the preliminary enrichment and recovery of Co and Ni resources can be realized, laying a foundation for their further purification.

Experiments were carried out to compare dephosphorization performance of CaCO₃, Na₂CO₃ and CaF₂ in direct reduction roasting process of high-phosphorus hematite. It is found that Na₂CO₃ presents the best dephosphorization performance, followed by CaCO₃. The molecular dynamics simulation was conducted to calculate the distribution of bridging oxygen and the mean square displacement (MSD) of oxygen atoms during the roasting process of the system with three different additives respectively, and the dephosphorization mechanism of CaCO₃, Na₂CO₃, CaF₂ during the direct reduction process of high-phosphorus hematite was explored. The results show that the mechanism of dephosphorization by additives is to inhibit reduction of apatite by increasing the content of free oxygen or the MSD of oxygen atoms in the system and reducing the oxygen atoms shared by Si and P in the system. It is found that the dephosphorization performance of additives is positively correlated with the MSD of oxygen atoms in the system.

High pressure grinding roll (HPGR) was used to comminute a copper smelting slag. An open-circuit test, edge-product cycling test and closed-circuit ball mill test were carried out using HPGR. The particle size of various products were measured, and the grinding results after HPGR were compared with those obtained after jaw crushing. The results show that after copper smelting slag is processed using HPGR and ball mill, the fine particle fraction of the products increases obviously, and the grindability increases by about 36 percentage point. It can be concluded that HPGR approach favors upgrading of grinding efficiency and beneficiation index in processing copper smelting slag.

High purity sodium aluminate was prepared with sodium aluminate solution by adopting a process consisting of evaporation, cooling crystallization, and dewatering for purification. The effects of additives on caustic ratio and crystallization products, as well as the function and behavior of sodium aluminate solution during evaporation and crystallization were studied. The results show that with NaOH as an additive, the caustic ratio of the solution system can be increased, and the product from evaporation and crystallization can be converted to NaAlO₂. By using NaAlO₂ as seed crystal and adjusting the caustic ratio of system to 1.36 with NaOH, the product of NaAlO₂ with purity of 88.1% can be obtained after evaporation at 100 ℃ for 2 h with stirring rate of 300 r/min. Then, after 1 h dewatering at 200 ℃ and 1 h purification with alcohol at 100 ℃, a kind of solid NaAlO₂ can be obtained with purity of 93.8% and crystal particles of 5-25 μm.

By means of X-ray diffraction, optical microscopy, scanning electronic microscopy, mineral liberation analysis and chemical analysis, the paigetite ore from Wengquangou mine in Liaoning Province was studied in terms of its chemical component, mineral composition and content, and the occurrence state of main minerals. After main dissemination characteristics of target minerals and key factors in mineralogy influencing beneficiation performance were ascertained, some corresponding separation techniques were proposed.

A Gamma-ray concentration meter based on Kalman filtering was designed, and the relationship between ray intensity attenuation and slurry concentration was established by analyzing the measurement principle of ray concentration meter. To suppress the disturbance of the results, an optimal estimation of ray intensity was actualized by using Kalman filtering. The corresponding concentration is segmentally simulated and calculated by using the least square method. The results show that the concentration meter can provide timely and accurate measurement, with a maximum error of 0.328 percentage points and a root mean square error of 0.194 percentage points, presenting effective improvement in accuracy.