A barite ore from Guizhou province is a typical microfine refractory carbon-containing ore with uneven grain size distribution and complex dissemination relationship among barite and gangue minerals. After being milled to a grinding fineness of -0.075 mm 90%, the ore was processed using kerosene and terpenic oil for decarburization, with sodium carbonate as the pH regulator, sodium silicate as the depressant and CY-30 as the collector for barite flotation. A close-circuit flotation test yielded 75.92% barite concentrate grading 93.55% BaSO₄ at 87.85% recovery.

The predominant minerals in a kind of high siliceous non ferrous metal tailings include quartz, alunite, dickite, sericite and pyrite. The quartz has relatively coarser grain size, while alumite and dickite are enriched in a relatively finer fraction. Furthermore, alunite, quartz, dickite and sericite minerals are complicatedly disseminated. Herein, tests were conducted to reclaim alunite and quartz therefrom. An alunite concentrate with SO₃ grade of 20.14% can be obtained by using a process consisting of desliming, desulfurization and alunite flotation. And then, the obtained alunite flotation tailings are subjected to a reverse flotation, yielding a quartz concentrate grading 96.38% SiO_2. It is shown that this flowsheet can actualize an efficient and comprehensive utilization of nonferrous metal tailings.

Flotation tests were conducted for a complex refractory copper-lead-zinc polymetallic sulfide ore bearing arsenic and silver. By using a new high-efficient sulfide ore collector (CYC) and an environment friendly lead depressant (CYZ), the test with a flowsheet consisting of rough grinding, copper-lead-silver bulk flotation, classification and regrinding, reagent removal and Cu/Pb separation produced a copper concentrate grading 22.42% Cu and 11 549.74 g/t Ag with corresponding recoveries of 73.77% Cu and 83.85% Ag, as well as a lead concentrate grading 13.96% Pb and 6.61% Sb with corresponding recoveries of 19.45% Pb and 11.10% Sb. It is shown that with this technique, an efficient Cu/Pb separation can be actualized, while the associated Ag and Sb minerals can also be reclaimed effectively.

Due to high oxidation rate of a lead-zinc sulfide ore, the on-site flotation practice presented poor beneficiation indices. In view of this problem, an optimized closed-circuit process consisting of two stages of roughing, two stages of scavenging, one stage of rough cleaning of combined roughing concentrates, two stages of cleaning and two stages of scavenging for roughing concentrates was proposed. With slime (800 g/t) and CD-2 (300 g/t) as pyrite depressants, CD-1 (600 g/t) and water glass (600 g/t) as gangue depressants, sodium sulfide (500 g/t) as a sulfiding agent, copper sulfate (500 g/t) as an activator, butyl xanthate (200 g/t) as a collector, and terpineol oil (21 g/t) as a foaming agent, a closed-circuit flotation test produced a bulk concentrate grading 16.25% Pb and 27.69% Zn with a lead recovery of 65.05% and a zinc recovery of 92.49%. Compared with the previous on-site flowsheet, the Pb grade and Pb recovery are improved by 2.24 percentage points and 9.36 percentage points, while Zn grade and Zn recovery up by 1.57 percentage points and 5.14 percentage points respectively.

A flotation experimental study was conducted to process a copper sulfide ore. A closed-circuit flowsheet consisting of copper preferential flotation and sulfur recovering from copper flotation tailings was adopted, resulting in a copper concentrate grading 23.01% Cu at 95.47% recovery and a sulfur concentrate grading 35.72% S at 58.48% recovery.

Flotation tests were carried out for a low-grade complex copper ore from Hubei province. The influences of grinding fineness, reagent type and dosage on flotation indices were investigated. A closed-circuit flotation flowsheet consisting of one stage of roughing, three stages of cleaning and three stages of scavenging was adopted to process this kind of ore with Cu grade of feed ore of 0.42%, grinding fineness of -0.074 mm 75.2%, butyl xanthate combined with Z-200 and sodium diethyldithiocarbamate as collectors, calcium hypochlorite combined with lime as regulator. As a result, a copper concentrate with Cu grade of 12.15% and recovery of 85.05% was recovered.

In order to solve the problem of high water content in JISCO iron concentrate, dewatering tests were conducted by adding filtration aid. The results show that the filtration aid, CYG-1, can improve filtration effect. With the addition of CYG-1 at an amount of 500 g/t, the water content in the filter cake of iron concentrate falls by 2.31 percentage points compared to the practice without adding filtration aid.

Based on computational fluid dynamics (CFD) method, a multiphase VOF model and Realizable k-εturbulence model were used to simulate flow characteristics of a large bottom-blown furnace with different blowing modes, and analyze a pre-stabilization process, motion characteristics of blown gas, gas-matte-slag interaction characteristics and mixing effect in molten pool. The results show that the large bottom-blown furnace has two oxygen lances for blowing, which can altogether generate an enhanced pneumatic agitation zone, resulting in a remarkable gas-matte-slag interaction in the furnace, thus providing good dynamic condition for the large bottom-blown furnace. The furnace with double lances blowing at an angle of 9° can bring a better agitation effect, leading to the gas content at a rate of 2.70%, average speed of 0.20 m/s and average turbulence energy of 0.059 m²/s² in the molten pool. There is severe internal disturbance and less splashing of melt in the molten pool, which is beneficial to improving smelting efficiency.

A process consisting of direct reduction roasting and magnetic separation was adopted to separate and recover iron and titanium from ilmenite rough concentrate. A single factor experiment was conducted to explore effects of several factors, including reduction temperature, reduction time, coal powder dosage, borax dosage, bentonite dosage, grinding fineness, and magnetic field intensity, on the grades and recovery of iron concentrate and titanium concentrate. Then, the optimal processing parameters were finally determined. A reduction roasting runs at 1 200 ℃ for 2 h by adding coal powder at an amount of 40%, borax at 2% and bentonite at 2%, with a grinding fineness of 84% -38 μm, followed by a magnetic separation with field intensity of 79.62 kA/m, resulting in an iron concentrate grading 82.57% Fe at 83.59% recovery, and a titanium concentrate approaching 49.23% Ti grade at 85.18% recovery. It is shown that good beneficiation and smelting indicators are obtained.

After an in-situ leaching of weathered crust elution-deposited rare earth ores with ammonium sulfate, the obtained tailings were taken to explore the variation of water content, pH value, Zeta potential with sampling depth, and then the total nitrogen content, nitric nitrogen, ammonium nitrogen and the main co-existing ions were also analyzed. The results indicate that the tailings samples were all acidic, and both water content and Zeta potential decreased with increasing of sampling depth. The residual ammonium salt in the ore body mainly exists in the form of water-soluble ammonium (11%-33%), and ion-exchange ammonium (59%-87%) in ammonium nitrogen, presenting the highest content in middle layer and the lowest content in surface layer. XRD analysis reveals that the content of clay minerals in the rare earth tailings positively correlated with the content of residual ammonium. In addition, high content of organic matter in the surface layer of the ore body leads to the highest content of co-existing cations Al³⁺ and RE³⁺ in the surface layer; while as for the ore body at deeper position, the content of co-existing cations Al³⁺ and RE³⁺ decreases obviously, and the co-existing anions SO₄^2- and Cl^- present an opposite variation trend.