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A leaching experiment was launched on silver ore whose silver content is 101.6g/t in Yunnan province, China. Technological mineralogy research of the ore indicates that the content of carbon which is bad for leaching is 2.23%. Leachable silver minerals mainly are oxidized silver, elemental silver and silver sulfide. And the theory leaching ratio of the silver ore is 67.43%. When the content of-74um is 75%; dosage of sodium cyanide is 4.5kg/t; dosage of lime is 0.5kg/t; velocity of agitation is 400r/min; leaching time is 24h, a best indicator which leaching ratio is 70.47% can be obtained. Meanwhile, silver in lixivium is 20.42mg/L.

Copper ore is the main mineral for the large deposits. Copper minerals are mostly consisting of chalcopyrite, secondly consisting of bornite, there are traces of processing copper blue and malachite, the mineral is disseminated by coarse granularity. This mineral is easy to processing. Production process was using by the process of grinding-flotation. After grinding fineness, lime dosage, sodium sulfide dosage, collector and frother dosage, were determined by the open test. Closed circuit experiment was conducted by those optimal conditions identified in the above test, the recovery of copper concentrate is 88.38% and the grade of copper concentrate is 14.37%.

In order to provide essential information for enterprises to exploit the iron ore of Yunnan province in China, properties of the ore were analyzed. Experiments of the best grinding fineness analysis and magnetic separation current were conducted. The result show that the ore is martite; when the grinding fineness content below 74um is 95%, and magnetic separation current is 10A (0.8T), iron concentrate with a grade of 65.40% and a recovery of 90.49% can be obtained. Sulfur and phosphorus content in the iron concentrate is 0.057% and 0.011%, respectively.

In the blast furnace production process, the high iron content in the sludge produced by collecting, Iron can be used as recycled raw materials. Experimental study found that the use of magnetic roasting - weak magnetic iron powder method of recovering technology is feasible. The optimum conditions are: the grinding fineness is 87%, calcination temperature is 750 °C, roasting time is 25min, magnetic current is 1.5A under conditions to obtain a grade of 59% recovery rate of 79.3% iron ore .

The dissolution equilibrium of galena within the entire pH range was theoretically calculated, which was based on coordination chemistry, thermodynamics and the mass balance principle of Pb2+ and S2- in pulp solution. The calculation result showed that the total lead concentration (CPbT) of galena decreased significantly with increasing pH below 7 or so; however, at pH of about 10, a reverse trend of CPbT may be observed. Within the pH range from 7 to 10, the CPbT of galena remained close and presents a minimum value of around 10-10 mol/L. This paper may provide a theoretical basis for the dissolution process of galena and its conditioning stage before benefication by adopting flotation method.

A craft of sodium hydroxide roasting-aqueous leaching process is investigated for the treatment of a high arsenic pyrite cinders, a common by-product in vitriol industry. The pyrite cinders, containing 58.27% Fe, and 0.98% As, was conducted for the craft. The results demonstrated that iron concentrate with 58.87% Fe, 0.13% As and 87.40% of arsenic removal percentage was obtained under the optimal conditions (a roasting temperature of 1000°C, a roasting duration of 120 min and a mass ratio of sodium hydroxide to pyrite cinders of 8%).This craft can be used to utilize pyrite cinders and produce qualified concentrate as iron-bearing feed for steel industry, which will help to solve the pollution of pyrite cinders and extend raw material sourcing for Chinese steel industry.

The dissolution equilibrium of cerussite within the entire pH range was theoretically calculated, which was based on coordination chemistry, thermodynamics and the mass balance principle of Pb2+ and CO32- in pulp solution. The calculation result showed that the total lead concentration (CPbT) of cerussite decreased significantly with increasing pH below 6 or so; however, at pH of about 10, a reverse trend of CPbT may be observed. Within the pH range from 6 to 10, the CPbT of cerussite remained close and presents a minimum value of around 10-4 mol/L. This paper may provide a theoretical basis for the dissolution process of cerussite and its conditioning stage before benefication by adopting flotation method.

In this study, an iron ore was investigated with high content of phosphorus and sulphur about 1.09% and 1.4%, respectively. The grade of Fe is about 30%, which is mainly composed of siderite, about 23.40% of iron is existed in the form of silicate, such as chlorite, canbyite, and a small amount of pyrite, magnetite. The phosphorous mainly occurred as apatite, which is close united with the phase of iron, and the sulphur mainly comes from pyrite. According to the mineralogy analysis of run-of-mine, acid leaching and reduction roasting with sodium carbonate is used for the high efficiently dephosphorization and desulfurization. Magnetic tube experiment after reduction roasting with sodium carbonate, an iron concentrate with 84.5%, Fe was produced with 69.7% relative recovery as a result of magnetic tube experiment carried out with 3A electric current.

The geometric and electronic structures of bornite (Cu5FeS4) were studied using the first-principle calculation based on density function theory. By analyzing the results, a mixed bonding state is found in bornite, which is a strong covalent bond with much weaker ionic bonds. The interaction between S and Fe is stronger than that between S and Cu. The main bonding orbitals are as follows: Cu: 3d104s1, S: 3s23p4, and Fe: 3d64s2. Fe center is to be reduced receiving electrons in its 3dorbitals and the S center is mostly to be oxidized.

Centrifugal High Gradient Magnetic Separation (CHGMS) was creatively developed, and in the present investigation was used for the concentration of fine ilmenite from tailings through a cyclic pilot-scale CHGMS separator, to study the effect of two key parameters, i.e., magnetic induction and rotation speed of matrix, on the separation performance of the separator. The results of investigation indicates that the CHGMS is effective in concentrating the ilmenite; an increase in the rotation speed increases concentrate grade but reduces recovery of TiO2, and this is reverse for the induction. While the two parameters were optimized, a concentrate assaying 19.42% TiO2 with 80.72% recovery of TiO2 is achievable from the tailings assaying 8.18% TiO2. It was concluded that the CHGMS provides a prospective technology for the concentration of fine ilmenite.

A craft of concentrated acid-heating reinforced leaching process is investigated for the treatment of a high arsenic pyrite cinder, a common by-product in vitriol industry. The pyrite cinder, containing 57.37% Fe, and 2.78% As, was conducted for the acid leaching process. The results demonstrated that iron concentrate with 60.57% Fe, 0.28% As and 96.23% of iron recovery was obtained under the optimal acid leaching conditions(Sulphuric acid concentration is a mass ratio of 20%, a leaching temperature of 60°C, a liquid-solid ratio of 2:1 and a leaching time of 120 min).This craft can be used to utilize pyrite cinder and produce qualified concentrate as iron-bearing feed for steel industry, which will help to solve the pollution of sulfuric acid residue and extend raw material sourcing for Chinese steel industry.

A Mo middling has been obtained through Cu-Mo bulk flotation. In order to further enrich molybdenite and separate pyrite form this middling. A series flotation tests were conducted to concentrate Mo. Important parameters including regrinding fineness, CaO dosage and cleaning flotation stages were optimized to enhance Mo enrichment. In addition, a close-circuit flotation test was conducted under optimum parameters and a Mo concentrate with 22.92% of Mo grade and 93.75% of Mo recovery was obtained, which satisfied the plant requirement.

The balling properties of pyrite cinder (PyC) with high content of copper are researched in this paper. The results indicate that grinding process is an effective way to improve the quality of green balls. Through the measuring of drop strength compressive strength and cracking temperature on pyrite cinder balls, it is found that the best bailing properties of PyC can be obtained under the recommended parameters (the content of grain size of PyC below 75 μm accounts to 95.75% and bentonite dosage is a mass ratio of 2%) and green balls with 5.4 frequency•(0.5m)-1 of drop strength, 15.8 N•each-1 of compressive strength and cracking temperature of about 700 °C are obtained, which can meet the requirements of metallurgical technology.

The study aims to remove copper from a pyrite cinders using chlorination roasting and optimizing the roasting parameters through response surface methodology (RSM). After a series of experiments, a quadratic model was suggested by RSM to correlate the variables to the copper volatilization ratio. The results indicate that the model is in good agreement with the experimental data and the dosage of chlorinating agent and roasting temperature play a key role in improving the volatilization ratio. The optimum conditions for remove copper from the cinders were identified as chlorinating agent dosage at 5%, roasting temperature at 1155.05 °C and roasting time of 10 minutes; under such a condition, an average copper volatilization ratio of 95.16% was achieved from the cinder.

The study attempts to produce iron concentrate from a high-purity pyrite concentrate using oxidizing roasting at industry scale. The effect of key parameters, i.e., roasting temperature, excess air coefficient and roasting intensity on the Fe and S content in the pyrite cinder was fully investigated. The results indicate that the roasting temperature plays a key role in decrease the S content in the pyrite cinder; an increase in the roasting temperature from 800°C to 950°C decreased the S content in the pyrite cinder remarkably from 0.43% to 0.18%. The optimum conditions for produce a high quality iron concentrate from the high-purity pyrite concentrate were identified as roasting temperature around 900 ~ 950°C, excess air coefficient at 1.20 and roasting intensity at 4.36 ~ 5.61 t / m2•day. Under such a condition, high-quality iron concentrate containing 65.11% Fe and 0.21% S was achieved from the pyrite concentrate.

A technology of “depth cleaning- sulfuric and acid producing- residuals for ironmaking” is proposed for efficient utilization of sulphur concentration with high quality. The effect of the main factors involving grinding fineness, activators, collector type and dosage was investigated. On this regard, a close-circuit flotation test scheme was proceeded, by which a high quality sulphur concentrate was obtained with 52.39% of iron grade, 86.44% of iron recovery, 39.46% of sulphur grade and 91.52% of recovery sulphur. This concentrate can be directly used in the production of sulfuric acid and preparation of iron concentrate. This technology can be used to fully utilize sulphur and produce high quality concentrate as iron-bearing feed for steel industry, which will help to extend raw material sourcing for Chinese steel industry.

A new technology of pellet production-drying-chloridizing roasting is proposed for valuable metal recovery from pyrite cinder with high content of lead and zinc. The pyrite cinder, containing 60.15% Fe, 2.02% Pb and 2.15% Zn, was pelletized with addition of 2% bentonite in pan pelletizer. Green balls after drying were roasting at 1100 °C for 60 min with 5 wt % of CaCl2 addition in tube furnace. The results demonstrate that pellets with 61.58% of TFe, lead and zinc volatile ratios of 98.02% and 96.83% were obtained. Key technique is that CaCl2 reacts with lead and zinc compounds and the chloride can be volatilized at moderate temperatures. This new technology can recover the valuable metal fully from pyrite cinder and produce qualified concentrate as iron-bearing feed for steel industry, which will help to solve the pollution of pyrite cinder and extend raw material sourcing for Chinese steel industry.

Large amount of sourrounding rocks in Jianshui China has been discarded for many years, and the “rock” is characterized by Cu-Fe polymetallic constituents and of low grade. According to the results of chemical and phase analysis as well as the mineralogy, a joint pocess of flotation and magnetic separation was proposed and used to process the ore. Flotation results show that the combined processing technology is efficient in utilizing the low grade rocks. A copper concentrate assaying 20.68% Cu at the recovery of 80.11% can be obtained, when the raw material assays 0.79% Cu.

The study aims to recovery of silver minerals from zinc leach residue by flotation method with mixed collectors, namely, ammonium dibutyl dithiophosphate (ADD) and diethyl dithiocarbamate (DD). The effect of key parameters, i.e., grinding fineness, dosage of collectors and dosage of sodium chloride on the flotation performance was investigated. The results indicate that dosages of ADD and DD have both significant effects on the flotation performance, and sodium chloride plays an important role in the increase of the grade of silver, by eliminating the detrimental effect of Zn2+ in the pulp. The optimum conditions for flotation of silver from the material were identified as grinding fineness of 90%, dosage of ADD at 400 g/t, dosage of DD at 75 g/t and dosage of NaCl at 60 g/t; under such a condition, a sliver recovery of 76.92% with a concentrate grade of 2012.30 g/t was achieved, and the tailing from the flotation has a lower sliver grade of 17.30g/t, with only 15.04% of silver lost in the tailing.

Based on the analysis of the properties of the ore from Weixin area in Yunnan province, a suitable technical route was presented for the processing of sulphur concentrate with high quality. The main factors i.e. grinding fineness, pH, collector type and dosage, affecting the quality of roughing concentrate was investigated. On this basis, a close-circuit flotation test scheme was proceeded, which obtained a high quality sulphur concentrate with sulphur grade of 51.58%, sulphur recovery of 99.22%, iron grade of 45.14% and impurities content of 3.28%. In addition, a decrease of slurry concentration of cleaning further increase the quality of sulphur concentrate, which contained 52.82% sulphur, 45.29% iron and 1.89% impurities.

The valuable minerals of a copper sulfide ore in Chile, mainly consist of chalcopyrite and chalcocite as well as contain small amounts of cuprite. Gangue minerals are mainly chlorite, quartz, calcite, arsenopyrite, etc. Most are coarse-grained disseminated minerals, while some are fine-grained disseminated minerals. Flotation has been used for processing these ores. The grinding fineness, lime dosage, collector type and dosage all have influences on flotation results. In the present work, the best condition of grinding fineness, lime, and collector dosage was used to separate the copper sulfide and other minerals in the ores. The results showed that, in the grinding fineness of −74 μm accounting for 80%, the vast majority of copper minerals were to monomer dissociation. The flowsheet of one stage roughing, two stage scavenging, and two stage cleaning was adopted. The ideal results of 27.58% and 96.89% for the copper concentrate grade and copper recovery, respectively, were obtained.

This study aimed to obtain volatile copper from a high-copper pyrite cinder by optimizing the chloridizing roasting process using response surface methodology (RSM). The effect of key parameters, i.e., dosage of CaCl2 addition, roasting time and roasting temperature, on the copper volatile ratio was investigated and a quadratic model was suggested by the methodology to correlate the variables to this volatile ratio. The results indicated that the model was in good agreement with the experimental data at a correlation coefficient (R2) of 0.9782, and the most influential parameter on efficiency was identified as the dosage of CaCl2 addition. The optimum conditions for chloridizing roasting from the high copper pyrite cinder were identified as a dosage of CaCl2 addition of 4.8 wt%, a roasting time of 19.28 min and a roasting temperature of 1151.51 °C; under such conditions, a copper volatile ratio of 97.82% was achieved. The pellets obtained by this process are characterized by a high content of hematite, and the main impurity element contents are consistent with the requirements for iron concentrate, which is suitable for use in ironmaking.

A technology of “arsenic removing- sulfuric acid producing- residuals for ironmaking” is proposed for comprehensive utilization of pyrite with high content of arsenic. The effect of roasting temperature and time on arsenic removing was investigated. The arsenic removed residuals obtained under the optimal arsenic removed conditions, was used to be proceeded for sulphur volatilization test. The results demonstrate that final residuals with 63.53% of Fe can be used for steel industry. This technology can be used to fully utilize sulphur and produce high quality concentrate as iron-bearing feed for steel industry, which will help to reduce the pollution of arsenic and extend raw material sourcing for Chinese steel industry.

For low-grade iron ore, smelting costs and resource wastage will be increased. Product quality of such ore is affected adversely by an excessive amount of sulfur. This also causes environmental pollution. In accordance with the vanadium-titanium (V-Ti) magnetite concentrate properties with low iron grade and high sulfur content, the joint process of magnetic separation and flotation was carried out. Magnetic separation was conducted to increase the iron grade, while reverse flotation was used to reduce sulfur content. Results show that the feeding mainly contains titanomagnetite, hematite, and pyrite. The sulfur was primarily found in pyrite. The separation effect was influenced by the grinding fineness, magnetic intensity, collector type and dosage, and pH value. At a grinding fineness of −45 μm accounting for 87%, most of the iron minerals exhibited monomer dissociation. An open-circuit experiment was carried out under the best conditions of magnetic intensity, as well as collector and modifier dosage. Good experimental results were obtained as follows: the iron grade increased to 57.17%, iron recovery was 89.94%, sulfur content decreased from 0.66% to 0.26%, reverse flotation of sulfur foam concentrate contained almost 15.68% sulfur, the upgrade ratio was about 23, and the cobalt in the sulfur concentrate was enriched 20-fold. A method for improving the comprehensive utilization level and effect of mineral resources is provided in this study.