scholarly journals Designing of engineering solutions to enhance efficiency of high-copper gold-bearing ore processing

Author(s):  
M.V. Zalesov ◽  
V.A. Grigoreva ◽  
V.S. Trubilov ◽  
A.Ya. Boduen

The modern metals industry is characterised by a downward trend in the quality of ores involved in processing, and conventional methods of extracting useful components are inefficient for raw materials with complex composition. To maintain the growing level of metal production it is required to introduce new efficient technologies for processing of low-grade and refractory ores as well as man-made deposits. The article describes processing methods of refractory raw materials with high cyanide content using copper-gold ores as an example, where gold is the primary commodity, and copper is the accompanying useful component. The most common method of processing copper-gold ores is preconcentration followed by selective leaching of copper and gold. In some cases, technologies involving copper by-products and cyanide recovery from the cyanide leaching solutions offer equally effective options for processing of the copper-gold ores and concentrates. Copper-gold ores are processed at gold mines using the cyanide procedures, supplemented if required by gravity and flotation concentration. In all variations of the cyanide treatment, most of copper minerals actively react with cyanides of alkali metals, binding the CN– ions into the copper complex of [Cu(CN3)]2–. This reaction results in an increased solvent consumption, as well as in number of challenges related to cleaning tailings and slurries from highly toxic cyanide compounds and dissolved copper. In addition to technological complications associated with the need to meet strict requirements for the maximum permissible concentrations, copper accumulated in the cycling solutions also causes a decrease in gold extraction from the processed ores.

2013 ◽  
Vol 825 ◽  
pp. 352-355 ◽  
Author(s):  
Zeng Ling Wu ◽  
Zhong Sheng Huang ◽  
Ren Man Ruan ◽  
Shui Ping Zhong ◽  
Brenda K.C. Chan

Low-grade, finely disseminated refractory sulfide gold ores associated with high arsenic are ubiquitous resources all over the world. Since heap bio-oxidation is an economic and promising biotechnology to recover gold, low grade, high organic carbon and arsenic bearing gold ores from Zhesang Mines in China were chosen for this purpose to study the key factors that would affect biooxidation. Pyrite and arsenopyrite (particle size 0.002-0.22 mm) were the main minerals from Mineral Liberation Analysis (MLA). Column biooxidation and cyanidation of mineral size < 10 mm were evaluated for its potential for gold extraction. Results showed that temperature was the main factor influencing sulfide oxidation. 58-67 % of sulfide was oxidized at 35-45°C after > 240 days of biooxidation with mixed mesophiles, while higher sulfide-S dissolution (77%) was obtained at 60°C. Sulfide-S fraction distribution revealed higher mineral decomposition, finer fractions and eventually higher sulfide oxidation at 60°C. Jarosite and scorodite were found from the residues at 60°C by SEM and EDX, which implies higher temperature accelerated arsenic precipitation. No elemental sulfur was detected during the biooxidation at 35-60°C. After bio-oxidation, column cyanidation was successfully demonstrated recovery of gold from the residues, with gold extraction rate reaching 66%.


2012 ◽  
Vol 174-177 ◽  
pp. 751-756
Author(s):  
Zi Fang Xu ◽  
Ming Xu Zhang ◽  
Jin Hua Li

In order to notably improve the mechanical properties and durability of low-grade cement-based material, superfine silica fume was used to modify the cement-based composite based on special perfomance and effects of nano powder. The mechanical performance and durability were investigated.Then the phase compositions,microstructure and morphologies of as-received cement-based composite were studied by X-ray Diffractometer、TGA-DTA and SEM. The results show that: the best formula of raw materials is 1:1:0.025:0.015, and hydration can be accelerated and increasing of hydration products is observed after modification. In the hardened cement matrix, microstructure is very compacted and C-S-H gel forms densed structure, so the structure defect is notably reduced. This means that both strength and durability of cement-based composite are notably improved by the addition of superfine silica fume.


Minerals ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 499
Author(s):  
Duong Huu Hoang ◽  
Doreen Ebert ◽  
Robert Möckel ◽  
Martin Rudolph

The depletion of ore deposits, the increasing demand for raw materials, the need to process low-grade, complex and finely disseminated ores, and the reprocessing of tailings are challenges especially for froth flotation separation technologies. Even though they are capable of handling relatively fine grain sizes, the flotation separation of very fine and ultrafine particles faces many problems still. Further, the flotation of low-contrast semi-soluble salt-type minerals with very similar surface properties, many complex interactions between minerals, reagents and dissolved species often result in poor selectivity. This study investigates the flotation beneficiation of ultrafine magnesite rich in dolomite from desliming, currently reported to the tailings. The paper especially focuses on the impact of the depressant sodium hexametaphosphate (SHMP) on the following: (i) the froth properties using dynamic froth analysis (DFA), (ii) the separation between magnesite and dolomite/calcite, and (iii) its effect on the entrainment. As a depressant/dispersant, SHMP has a beneficial impact on the flotation separation between magnesite and dolomite. However, there is a trade-off between grade and recovery, and as well as the dewatering process which needs to be considered. When the SHMP increases from 200 g/t to 700 g/t, the magnesite grade increases from 67% to 77%, while recovery decreases massively, from 80% to 40%. The open circuit with four cleaning stages obtained a concentrate assaying 77.5% magnesite at a recovery of 45.5%. The dolomite content in the concentrate is about 20%, where 80% of dolomite was removed and importantly 98% of the quartz was removed, with only 0.3% of the quartz in the final concentrate. Furthermore, the application of 1-hydroxyethylene-1,1-diphosphonic acid (HEDP) as a more environmentally friendly and low-cost alternative to SHMP is presented and discussed. Using only 350 g/t of HEDP can achieve a similar grade (76.3%), like 700 g/t of SHMP (76.9%), while obtaining a 17% higher magnesite recovery as compared to 700 g/t of SHMP. Interestingly, the proportion of hydrophilic quartz minerals ending up in the concentrate is lower for HEDP, with only 1.9% quartz at a recovery of 21.5% compared to the 2.7% of quartz at a recovery of 24.9% when using SHMP. The paper contributes in general to understanding the complexity of the depressant responses in froth flotation.


2021 ◽  
Vol 1028 ◽  
pp. 365-370
Author(s):  
Diba G Auliya ◽  
Soni Setiadji ◽  
Zulfi Mofa Agasa ◽  
Fitrilawati ◽  
Norman Syakir ◽  
...  

Polydimethylsiloxane (PDMS) has been widely used as a vitreous humour substitution in vitreoretinal surgery. Due to its limited availability and increasing domestic needs, the price of PDMS in Indonesia became very expensive. Previously, we reported the synthesized of PDMS from a high grade of monomer of 98% of Octamethylcyclotetrasiloxane (D4) and found that all PDMS samples produced high quality samples similar to that of commercial one. However, by considering the ease of obtaining raw materials and also the production costs, the synthesis of PDMS using monomer which easy to be found in Indonesia and low production costs is needed to be developed. Here, we reported the synthesis of PDMS using low grade of 96% of D4 in order to produce high quality of PDMS with low viscosity that can be used for vitreous humous substitution in vitreoretinal surgery. PDMS samples with low viscosity value of 0.94-1.35 Pa.s have been successfully synthesized from low grade of D4 and MM using ring-opening polymerization method. The yields of PDMS resulted in this research were in the range between 67.27% and 76.26%. From FTIR spectroscopy, it is found that all synthesized samples have structure and functional groups similar to PDMS using high grade of monomer of 98% Octamethylcyclotetrasiloxane (D4). From refractometer and surfgauge measurements, all samples have refractive index in the range of 1,4034-1,4040 and the value surface tension was 21 m.N/m.


Metals ◽  
2018 ◽  
Vol 8 (12) ◽  
pp. 1025 ◽  
Author(s):  
Fei Zhu ◽  
Libo Zhang ◽  
Haoyu Li ◽  
Shaohua Yin ◽  
Sivasankar Koppala ◽  
...  

At present, gold mines are increasingly scarce in the world. The yield of cyanidation tailing (CT) of refractory gold ores with a grade of 10 g/T is huge; however, the effective capitalization of the cyanidation tailing is a significant problem in the gold industry. In this work, a new treatment method, a microwave-roasting process developed. The effect of roasting temperature, calcium chloride concentration, holding time and mineral size on the recovery of Au researched under conventional and microwave conditions. It found that, under the same processing conditions, the Au recovery in the microwave field is much higher than that of conventional conditions. The preliminary reinforcing role of the microwave discussed in the recovery of gold. This might be because of the microwave absorption ability of CaCl2 is much better, heated quickly and the reactions intensified among CaCl2, O2, and H2O. As a result, the extraction of gold in CT drastically increased in the microwave field, and the microwave roasting technology shows the characteristics of environmental protection in terms of low energy consumption and high efficiency.


2017 ◽  
Author(s):  
Софья Ярусова ◽  
Sof'ya Yarusova ◽  
Павел Гордиенко ◽  
Pavel Gordienko ◽  
Иван Жевтун ◽  
...  

The monograph presents general information on the main components of fluorite-containing ores and wastes and the results of studies on the possibility of complex processing of fluorite-containing mineral raw materials and wastes of the Yaroslavskiy ore-dressing combine with the extraction of beryllium compounds, alkali metals, fluoroammonium salts, as well as associated products in the form of gypsum, amorphous silica. Also, earlier studies related to this problem are summarized. The monograph is intended for specialists in the field of chemistry, chemical technology, ecology, scientists, graduate students, undergraduates involved in the complex processing of mineral raw materials and man-made wastes.


2021 ◽  
Vol 13 (2) ◽  
pp. 161-169
Author(s):  
Tatyana ALEXANDROVA ◽  
◽  
Anastasia AFANASOVA ◽  
Nadezhda NIKOLAEVA ◽  
◽  
...  

There is a worldwide trend of increasing the share of extraction and processing of low-grade minerals, but their extraction and processing volumes are still low. There are several reasons for this: high mining and transportation costs, imperfect techniques and technological difficulties in enrichment and processing of refractory and low-quality minerals. Due to the depletion of reserves of easily beneficiated raw materials and to compensate for the growing shortage of high-quality minerals, the Russian mining industry development strategy provides for the involvement of new and unconventional types of deposits into production. Examples of such deposits are deposits of carbonaceous raw materials (black shale, refractory sulphide carbon-bearing ores, impactites, etc.) containing carbon of varying degrees of metamorphism. On the basis of the most modern mineralogical, physical, nuclear and chemical methods of research of composition, structure and properties of the carbonaceous raw materials at the micro- and nanolevel, the composition of the productive mineral matter, physical, chemical and thermodynamic laws of separation of valuable mineral components and the basic technological processes to obtain the finished product for valorization of the unconventional carbonaceous mineral raw materials were determined with maximum reliability. One of the possible reasons of difficulty of beneficiation of carbonaceous raw materials is the fine phenocrysts in graphite which can be solved by using the flotation process. Contrast of surface properties of minerals with similar technological properties can be increased by application of different energy effects (MEMI, MIO, microwave, electrochemical treatment etc.) at successive stages of raw material transformation, regulation of pulp conditioning conditions (duration and intensity of agitation, heat treatment of pulp) as well as by development and application of selective reagent regimes. The special feature of flotation as a method of extraction of noble and rare metals is the ability to extract valuable metals not only in their native free form, but also in close association with sulphides and carbon. Flotation with the use of intensifying influences made it possible to transfereven low-sized structures of noble and rare metals, which are not extracted by conventional methods of cyanidation, gravitation enrichment and amalgamation, into the concentrate. One of the ways to increase the efficiency of the flotation process is preliminary modification of the additive which is introduced in addition to the main reagents of the sinter - “carrier material”.


2013 ◽  
Vol 804 ◽  
pp. 52-56
Author(s):  
Yan Ping Feng ◽  
Zhi Wen Qiu ◽  
Xiao Bin Ma ◽  
Lei Zhao ◽  
Xin Chao Chen ◽  
...  

In order to lay raw materials foundation for increasing the performance of insulating brick with the low grade quartz sand along the Yangtze River, the quartz porous ceramic materials was researched in this paper. The results show the porosity of the porous quartz ceramics decreased with an increase in the sintering temperature. The pore is like the bowl shape, and the pore is closed pore, which is help to improve the heat insulation property of quartz porous ceramics. The CaSiO4 is produced in the ceramics after sintering processing. The shape is better, and the microstructure is circular and symmetrical pore, which is help to improve the mechanical property of quartz porous ceramics.


Author(s):  
Anna Alfocea-Roig ◽  
Sergio Huete-Hernandez ◽  
Alex Maldonado-Alameda ◽  
Jessica Giro-Paloma ◽  
Josep Maria Chimenos-Ribera ◽  
...  

Climate change has become one of the world’s leading threats. Currently, the construction industry has a high environmental footprint. For this reason, the scientific and technological sector is looking for new materials to reduce the environmental consequences of this division. It is well known that the valorisation of different by-products can contribute to the reduction of the energy global consumption and CO2 emissions. Magnesium Phosphate Cement (MPC) can be obtained by using Low Grade Magnesium Oxide (LG-MgO) as a by-product from the industrial process of magnesite calcination. In this research, a Sustainable MPC (Sust-MPC) for different construction purposes is developed by using LG-MgO along with monopotassium phosphate KH2PO4 (MKP) as raw materials. The increasing use of synthetic fibres in clothing, as well as China’s competitive prices on Animal Fibres (AF) market, have led to a commercial interest fibre decrease for wool-like AF in Spain. This study aims to formulate a Sust-MPC cement with Animal Fibre (AF) to reduce the cost of the new material (Sust-MPC-AF) and to increase the thermal insulation, allowing the use of Sust-MPC-AF in several potential applications. Besides, it should be emphasized that the final pH of Sust-MPC is neutral, which allows containing natural fibres. To develop Sust-MPC-AF, some properties such as thermal conductivity, density, Modulus of Elasticity (MoE), flexural strength, and economic cost were evaluated using the Design of Experiments (DoE). The DoE studies allowed obtaining a model for further optimization considering minimum thermal conductivity and cost dosages. The formulation 30L-25EW presents the minimum conductivity (λ=0.140 W·m-1·K-1). Therefore, two optimal dosages (36L-25EW and 24L-22EW) are obtained by considering mixing variables such as AF/Cement ratio (AF/C) and AF/Extra Water ratio (AF/EW).


Author(s):  
D. A. Serebryanskii ◽  
M. N. Korolev ◽  
M. V. Antonov ◽  
I. O. Tyapkova

Metallurgical production associates with such processes as crushing, drying and pneumatic transportation of raw materials, roasting, melting etc., in the process of which hard particles and harmful gaseous components are emitted into atmosphere. At pneumatic transportation of raw materials and sand, their concentration in the atmosphere as a rule exceeds maximum permissible concentrations. Existing facilities of dusty flows cleaning in some cases don’t ensure sanitary norms ГН 2.1.6.3492‒17. Technical solutions  proposed  to  clean  gases  in  a  centrifugal  filter,  a  facility  of  complex  gas  cleaning – cyclo-filter and two-stage  system  of high-concentrated gas-dust flows cleaning. Description of the centrifugal filter, cyclo-filter, two-stage facility of gas cleaning design presented. The facility comprises centrifugal filter and ceramic pulse filter. Industrial tests of the centrifugal filter ЦФ2-6-1 under conditions of a system of pneumatic transportation of sand established, that efficiency of gas-dust flows cleaning of sand particles in a  six-channel  filter  can  reach 98.65%.  Application of  two-stage  system  of  gas  cleaning  comprising  centrifugal  filter  and  ceramic pulse filter ФКИ enables to reach residual hard particles concentration at the exit of such a facility of 5 mg/m3, having initial dust level of 127878 mg/m3. Application of such a complex two-stage cleaning facility allows to reach values of 0.1 of maximum permissible concentrations near the source of emissions.


Sign in / Sign up

Export Citation Format

Share Document