Showing papers on "Beneficiation published in 1998"

Hydrophobic flocculation flotation for beneficiating fine coal and minerals

Abstract: It is shown that hydrophobic flocculation flotation (HFF) is an effective process to treat finely ground ores and slimes so as to concentrate coal and mineral values at a fine size range. The process is based on first dispersing the fine particles suspension, followed by flocculation of fine mineral values or coal in the form of hydrophobic surfaces either induced by specifically adsorbed surfactants or from nature at the conditioning of the slurry with the shear field of sufficient magnitude. The flocculation is intensified by the addition of a small amount of nonpolar oil. Finely ground coals, ilmenite slimes, and gold finely disseminated in a slag have been treated by this process. Results are presented indicating that cleaned coal with low ash and sulfur remaining and high Btu recovery can be obtained, and the refractory ores of ilmenite slimes and fine gold-bearing slag can be reasonably concentrated, leading to better beneficiation results than other separation techniques. In addition, the ...

A process for the production titanium concentrate having a chemical composition similar to ilmenite from highly impure anatase ores

Abstract: The present invention relates to a process for concentrating highly impure titanium ore, such as anatase, with the main purpose of obtaining a final concentrate having a chemical composition similar to that of ilmenite. The process is based on the use of the following sequence of operations for the beneficiation of titanium ores: disintegration, screening, crushing, classification, low intensity magnetic separation, attrition and slimes removal, calcinations in the presence of sodium carbonate (Na2CO3) and/or potassium carbonate (K2CO3), comminution of the calcinations to a partied size below 1 mm, leaching in alkaline medium (pHin excess of 10) followed by acid leaching, The final concentrate, which is rich in titanium and iron and has a low content of impurities, is the intermediate raw material for the process of producing titanium slag.

Process for beneficiating kaolin clays

Abstract: A improved process for beneficiating kaolin clays to remove discoloring impurities is disclosed. The beneficiation of kaolin clay is improved by fractionating a kaolin clay starting material into a lower brightness first fraction having a majority of the discoloring impurities and a higher brightness second fraction with less impurities. The first fraction is then beneficiated (such as by flotation, selection flocculation, high intensity magnetic separation and/or leaching) to produce a kaolin clay product with improved optical properties. The first and second fractions may be combined to produce a product with improved optical properties.

Enrichment of the manganese content by wet high intensity magnetic separation from Chikla manganese ore, India

Abstract: Manganese ores from Chikla region, Bhandara district, Maharastra, India, by and large are low and medium grade types and need beneficiation to utilise them in ferromanganese industry. Isodynamic separation followed by chemical characterisation of ores from this region indicated their susceptibility to Mn enrichment. Details of characterisation, heavy media and magnetic separation studies carried out on a medium grade manganese ore, containing 44% Mn, 7.8% Fe and 22% acid insolubles, from the Chikla region are presented. By processing the material on a wet high intensity magnetic separator, a product with 51% Mn at 95% recovery could be obtained.

Trace Elements During the Mining and Beneficiation of Coal

Abstract: Relevant published information is reviewed and assessed for the effects of mining and beneficiation on trace elements in coal. In general, the concentrations of those elements associated with mineral matter are decreased to varying degrees depending on coal properties and beneficiation processes. The removal of much of the pyrite in coal means that consideration must be given to pyrite-enriched wastes. The removal of most trace elements by beneficiation is an environmental bonus. Proper control of wastes during mining and beneficiation should overcome potential problems from the mobilisation of trace elements.

Process for the beneficiation of waste material and the product developed therefrom

Abstract: An iron based product having at least a sufficient total ferrous content by weight to render the product commercially feasible wherein the product is derived by a process comprising the beneficiation of kish slag waste material having a relatively low ferrous material content before beneficiation. The resulting iron based product has a total ferrous content of substantially 90% by weight thereby making it both practical and economical for the reintroduction into iron and/or steel making processes utilizing an injection method or by briquetting at at least a portion of the resulting product. The beneficiation process involves the heating of the waste material to an extent at least sufficient for drying, separating the high sulphur slag from a remainder of the waste material and subsequently classifying the remainder of the waste material, once separated from the high sulphur slag by particle size. The classified, substantially larger particle size waste material is then ground until a predetermined range of particle sizes are present and until the general particle size of secondary material products with little or no ferrous content are reduced below the general particle size of the remaining primary iron based product which do not readily reduce in size under the grinding. Subsequently, the particles are again classified so as to remove and collect the primary iron based product particles that remain above a predetermined mesh size from the processed waste material.

Upgrading schemes for boron minerals through calcination

Abstract: Despite its importance in various diverse industries, research on beneficiation strategies of boron minerals has not received enough attention. Boron minerals are primarily upgraded by wet processing methods. However, severe environmental constrains have accelerated the development of dry processing techniques such as calcination. Interestingly, the boron minerals colemanite, ulexite and borax undergo decrepitation, shrinkage and expansion, respectively, upon heat treatment. Each mineral then requires a different beneficiation scheme. In this study, laboratory and pilot-plant studies conducted in our laboratories on the calcination of boron minerals are briefly reviewed and their implications to commercial operations are discussed.

Flotation of Sulphide Ores - HZL Experience

Abstract: Flotation process, patented in the year 1906, was origin-ally developed for mineral industry to recover values from high grade tailings of gravity seperation plants. This technology has acclaimed importance as a versatile process for the beneficiation of vast variety of sulphide mine-rals. Due to flexibility of the process and remarkable development taken place in flotation technology and its ancillary systems, it has now become possible to recover fine grained sulphide minerals from compiled ore deposits, whose processing was earlier considered un-economical. Today, about 400 million tonnes of sulphide ore is treated annually by flotation process worldwide. M/s Hindustan Zinc Ltd. (HZL), a leading lead-zinc mining and smelting company in India has experienced a spect- acular growth from the time of its inception. Starting from a single 500 MT per day lead-zinc mine at Zawar, HZL has expanded its mining capacity to about 13,000 MT per day with matching ore beneficiation plants, all adopting froth flotation technology.

Beneficiation with selective flocculation using hydroxamates

Abstract: A process which uses selective flocculation with hydroxamates for the beneficiation of mixtures of mineral particles (such as kaolin clays). The increased selectivity of hydroxamates for certain mineral phases within kaolin clays and other mixtures of mineral particles improves the process over selective flocculation processes utilizing other activators.

Amenability of column flotation for lead-zinc beneficiation - A case study

Abstract: The amenability of column flotation technology for the beneficiation of lead and zinc was studied by installing a 3.0 inch dia notation column. Systematic tests were conducted to depress pyrite and graphite and to improve the quality of lead concentrate. The results clearly indicate that the complexity of the existing flotation circuit can be simplified by adopting flotation columns. In the case of zinc, single stage cleaning by flotation column was found to be sufficient instead of four stage cleaning by conventional cells. However two stage column cleaning is essential in the place of existing three stage cleaning by conventional cells to obtain high grade concentrates of lead.

Fine coal and three product dry beneficiation with vibration and double-density fluidized beds

Abstract: The fluidizing performance and density uniform stability of vibration fluidized beds were analyzed. The experimental results in 2000 mm×80 mm×200 mm model apparatus show that the vibration fluidized bed can efficiently separate fine coal of size 6–0.5 mm, the beneficiation lower limit is 0.5 mm, the Ep value is 0.07. A double-density fluidized bed was formed by which the bed structure was specially designed with a pyramidal part. It can efficiently turn out three products according to densities in a fluidized cascade. The suitable range of gas flow rate is 4.4–4.6 m3/h. In the lighter area, the separation density is around 1.49 g/cm3, and Ep value is 0.06. In the denser area, the separation density is about 1.85 g/cm3, and Ep value is 0.07.

Four-dimensional trend surface analysis and its implications on the distribution of Ni, Co, Fe2O3, Cr2O3, SiO2 and Al2O3 in the nickeliferous laterite overburden of South Kaliapani chromite deposit, Sukinda ultramafic belt, Orissa, India

Abstract: Four-dimensional trend surface analysis is applied to the geochemical data generated on the drill core samples of the nickeliferous lateritic overburden of South Kaliapani mine to understand the distribution of Ni, Co, Fe2O3, Cr2O3, SiO2 and Al2O3. The distribution can be used to delineate different ore zones which will help in selective mining/removal of overburden, blending and beneficiation of low grade ores depending on the purpose of their use like nickel extraction, development of ferro-nickel and/or ferro-chrome.

Flotation of Sulphide Ores - HZL Experience

Abstract: Flotation process, patented in the year 1906, was originally developed for mineral industry to recover values from high grade tailings of gravity separation plants. This technology has acclaimed importance as a versatile process for the beneficiation of vast variety of sulphide minerals. Due to flexibility of the process and remarkable development taken place in flotation technology and its ancillary systems, it has now become possible to recover fine grained sulphide minerals from complex ore deposits, whose processing was earlier considered uneconomical. Today, about 400 million tonnes of sulphide ore is treated annually by flotation process worldwide. M/s Hindustan Zinc Ltd. (HZL), a leading lead-zinc mining and smelting company in India has experienced a spectacular growth from the time of its inception. Starting from a single 500 MT per day lead-zinc mine at Zawar, HZL has expanded its mining capacity to about 13,000 MT per day with matching ore beneficiation plants, all adopting froth flotation technology. The phenomenal progress is a result of HZL's emphasis on research and development with an objective to improve the efficiency and to optimize performance, and to seek innovative modern technology and control systems in their flotation plant and processes. This has not only solved metallurgical problems but improved overall plant economics. High grade concentrates produced with reduced deleterious impurities have further enhanced smelting efficiency. The paper covers general principles and aspects of industrial sulphide ore flotation practices in brief and processes adopted in HZL's plants. It also highlights R&D efforts made and new technologies adopted in one of the most complex sulphide ore beneficiation plants to solve metallurgical problems in flotation process.

On-stream X-ray diffraction analysis of phosphate rock-bearing slurries in Florida: a case study towards process control

Abstract: A system for the on-stream X-ray diffractometric determination of mineral phases in slurries was developed, in response to the mining industry's need for process control during the beneficiation of industrial minerals. The instrumentation for, and results from testwork conducted at a phosphate rock beneficiation plant in Florida are discussed. Results show that the concentrations of the minerals apatite (var. francolite) and quartz can be accurately determined every few minutes, so that adjustments to the flotation circuit can be executed from the control room when needed. The on-stream measurements can ultimately be integrated into an automated plant control system. Estimates of savings on reagent and manpower costs, as well as the benefits from consistent grades and greater recoveries, have shown that the investment in such a system could be recovered in less than a year.

Aerodynamic separation of disperse minerals and materials

Abstract: The paper sums up experimental studies on aerodynamic separation of disperse-type rocks with special reference to beneficiation of Callovian clays and reports the natural radionuclide content of various minerals and materials. Basically new, competitive designs of aerodynamic separators are reported.

Beneficiation of locally available sand for the manufacture of colourless glass

Abstract: The investigation of Noapara glass sand deposit of Sylhcl di"J_rict is performed to beneficiEltc the sand for Ihc manufaclure of colourless glass. First of all the physical and mineralugical identlficatlOn of heavy' minerals present in the sand were carried out, The study includes sieve analysis, heavy mineral separation and magnetic separation. SemI-quantitative analyses of the glass sand were performed wIth the help of XRD and Petrography and the results arc reported in sequence. The classified sand is then subjected to water wash and attrition to remove clay and ferruginous coating followed by magnetic separation to eliminate magnetic minerals. The waler-washed and magnetically treated sands arc then subjected [0 vanous chemical treatments in order to reduce the iron level. Finally. a number reagent batch combinations are prepared using water-washed and magnetic treated sand for the forth flotation le<.:hmque. One of such reagent combinations reduce Fe203 and Cr203 levels in the sand to 0.032 and 0.0012 % respectively after froth flotation. This is close to the required chemical composition for Ihe manufacture of colourless glass.

Beneficiation of a lean-grade siliceous rock-phosphate ore from Hirapur, India

Abstract: Froth flotation was employed to beneficiate a lean-grade siliceous rock-phosphate ore containing fluorapatite, the phosphate-bearing mineral. The main gangue minerals were quartz, iron oxides and aluminum oxides. After the rougher stage, four cleaning stages were required to upgrade the ore. The liberation size of the phosphate mineral was below 200 mesh, The reagent scheme consisted of commercial-grade sodium silicate and sodium oleate. The effect of reagent dosages, number of cleaning stages and pulp density on the efficiences of separation were studied systematically. A flowsheet was proposed for the processing of low-grade siliceous phosphate ore containing 12.1% P2O5, 55.36% SiO2 and 15.45% CaO. The flowsheet provided a useable phosphate concentrate containing 34.18% P2O5 and 14.20% SiO2 with a P2O5 recovery of 70.4% (the weight yield was 25.0%).

Composition for preparing artificial porous fillers

Abstract: FIELD: building materials industry, more particularly, thermal insulation of building structures. SUBSTANCE: claimed composition comprises (wt %): 36-46 product of condensation of actone-phenol production waste with formaldehyde; 24-34 acid catalyst; 11-36.1 marl; 1.1-19 asbestos-serpentine waste resulting from asbestos ore beneficiation. EFFECT: improved properties of the composition.

Refinement of methods of beneficiation of finely disperse minerals

Abstract: The prospect of switch-over of the industry to processing lean materials raises the problem of beneficiation of finely disperse placers of noble metals, the profitability of realization of which lies in raising the efficiency of separation processes by reducing frictional forces in the course of implementation of the technological processes and by employing modern technologies for beneficiation. The engineering—technological solutions worked out are distinguished by ecological safety during implementation of the beneficiation processes. The proposed schemes of beneficiation and primary processing of finely disperse minerals may be used:

A process to improve mineral flotation separation by deoxygenating slurries and mineral surfaces

Abstract: A process for the separation of minerals of different mineralogical character. The process involves conditioning a milled slurry or flotation concentrate of a mixture of valuable sulphidic minerals and non-sulphidic gangue material with an inert/non-oxidising gas and/or a reducing/deoxifying agent. The conditioning is conducted to achieve a controlled dissolved oxygen content or electrochemical reduction potential conducive to the separation of the valuable sulphidic mineral, non-sulphidic gangue material. The inert/non-oxidising gas and/or reducing/deoxifying agent may be added to the milled slurry or flotation concentrate in a quantity sufficient to increase rejection of the non-sulphidic gangue minerals or to improve the selectivity between the valuable sulphidic minerals and non-sulphidic gangue minerals.