Shao Jun Bai

Investigation on Beneficiation Strategy for Collophane

Phosphate being one of the three major nutrients required for agricultural plant growth usually presents as collophane in China. Since fine phosphate and other gauge minerals associate with each other and form intergrowth, the beneficiation of collophane is extremely difficult. In this paper, the flotation strategy for a low grade collophane ore from Guizhou province in China was studied in detail. Direct, reverse and direct-reverse combined flotation sheets were employed to collophane flotation. The results reveal that direct-reverse flotation is a suitable flotation flow sheet for this collophane ore. With direct-reverse flotation sheet, the grade of P2O5 in concentrate is 33%, which is improved by 3% comparing direct flotation and P2O5 recovery could achieve 80%. In addition, content of MgO decreased to 0.9%, which satisfied the requirement of wet-process phosphoric acid.

Efficient Utilization of Copper Sulfide Ore in Chile by Flotation

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.

Recovery Cu from a Copper Oxide Ore by Flotation and Leaching

The copper oxide ore is high oxidation ratio and the high combination ratio with a low grade of Cu 0.71%. Copper concentrate of Cu 15.02% with a recovery of 38.55% was obtained by flotation. The optimum acid leaching conditions were investigated. Effects of lixiviant concentration, solid-to-liquid ratio, leaching time were investigated. The acid leaching efficiency was 78.75% relative to flotation tailings. By the combination of flotation and acid leaching flotation tailings, most of the Cu in the minerals can be enriched, the total recovery of copper reached 86.85%.

Research on the Magnetizing Roasting and Magnetic Separation of Blast Sludge

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 .

Arsenic Removal from Pyrite Cinders by Oxidizing Roasting with Sodium Hydroxide Addition

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.

Internal Geometric and Electronic Structures of Natural Bornite Crystal

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 3d orbitals and the S center is mostly to be oxidized.

Preparation of Magnetic Nanoparticles from Byproduct of Titanium Dioxide-Copperas

A new method for the preparation of Fe3O4 NPs from byproduct of titanium dioxide-copperas was studied in this study. Core-shell structures and chemical composition of the nanoparticles have been investigated by TEM, XRD and FTIR techniques. The results indicated that the Fe3O4 NPs can be synthesized and obtained from copperas by chemical co-precipitation method and have a uniform spherical morphology with an average diameter of about 10 nm. The mole ratio of Fe2+ to Fe3+was one of the most important factors during the chemical co-precipitation processing, which has a great effect on the yield and size distribution of precipitations. The recommended mole ratio f Fe2+ to Fe3+ was 1.75:1. The saturated magnetization of Fe3O4 NPs was 52.8emug-1 at 25°C and this material exhibited excellent magnetic properties. A new way was therefore provided for the comprehensive utilization of the unmarketable copperas. Moreover, the Fe3O4 NPs obtained from the copperas have a big potential in environmental decontamination, medical technology and biological science.

Research on Balling Properties of Pyrite Cinder with High Content of Copper

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.

Preparation of Novel Magnetic Fluorescent Microspheres Obtained by Chemical Method

The aim of this study is to analyze the properties of microspheres, which was obtained from an iron tailings. The flow-sheet of chemical method consists of chemical co-precipitation of Fe3O4 magnetic microspheres, SiO2 packaged and amino silicon alkylation modification with anthrone under NaBH4 existence. The results show that microspheres can be obtained successfully and it not only has a strong magnetism, but also has a fluorescence effort with the irradiating processing by ultraviolet with a wavelength of 282nm. This microsphere particle is a kind of high-value, environmentally-friendly products, it can be traced and served as a magnetic guide due to its magnetism and fluorescence properties, which has a big potential in medical technology and biological science.

Recovery of Iron from a High Phosphorus and Sulphur Iron Ore by Using Various Methods

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.