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The nickel laterite ore from a mine in Philippines was analyzed for systematic process mineralogy. The results show that the ore sample contains 44.83% iron, 1.96% silicon, 1.18% magnesium, 1.02% nickel and 0.12% cobalt. It is a typical limonitic lateritic nickel ore. The main minerals in the samples are goethite, chrome spinel, quartz and other clay minerals, nickel and cobalt are mainly in iron minerals, and also in other minerals, and no nickel and cobalt minerals exist independently. Based on the characteristics of the minerals, the high- pressure sulfuric acid leaching process was chosen to treat the minerals. The leaching rate of nickel and cobalt is both 95% above, and the leaching rate of iron is less than 1% under the conditions including acid dosage of 29 g for 100 g mineral, temperature of 250 °C, liquid-solid ratio of 3 mL/g, and reaction time of 30 min, which realizes the selective leaching of nickel and cobalt The process mineralogical analysis of the leaching residue was carried out to analyze the causes of incomplete leaching of nickel and cobalt, During the leaching process, the acicular ferrite mineral phase in the raw ore is destroyed, and the nickel and cobalt endowed in it are leached into the solution, while the nickel and cobalt that are not leached are deposited in the chrome spinel, which is the main reason for the incomplete leaching of nickel and cobalt. The main sulfur-containing phase in the leaching residue is alunite produced by aluminum hydrolysis. In addition, the leaching slag may also contain part of the sulfate such as magnesium sulfate, both of which are closely combined with iron minerals. The sulfur-containing minerals in the leaching residue are tightly bound to iron minerals, so chemical desulfurization is required to remove the sulfur and realize its comprehensive utilization. [ABSTRACT FROM AUTHOR]

Two-stage pressure leaching process is proposed to extract Ni from limonite-type and saprolite- type nickel laterite ore. The recommended conditions for the first stage high pressure acid leaching include acid ore ratio of 330 kg/t, temperature of 250 °C, slurry solid content of 30% and reaction time of one hour. The recommended conditions for the second stage pressure leaching include temperature of 230 °C, reaction time of one hour and slurry solid content of 35%. The nickel extraction rate of first stage high pressure acid leaching and second stage pressure leaching is 97.58% and 83.96% respectively, and the total nickel leaching rate is 93.81%, which greatly improves the utilization rate of nickel laterite ore resources. The Fe and Al concentration in solution can be reduced to below 1 g/L, which can reduce the amount of alkali used in subsequent neutralization processes. [ABSTRACT FROM AUTHOR]

Pressure hydrometallurgy is one of the special metallurgical technologies, which is widely used in the separation, extraction, metal reduction and mineral synthesis of alumina, laterite nickel ore, sphalerite and gold ore. The development history of pressurized hydrometallurgy technology in China for more than 60 years shows that the production process, technical equipment and scale have reached the world advanced level. In the face of the increasingly fierce competition in the domestic and foreign non-ferrous metal market, energy conservation, emission reduction and environmental protection awareness, as well as the more stringent technical requirements of the production process, the pressure hydrometallurgy technology has increasingly shown its inherent technical advantages in the efficient and clean utilization of complex and low-grade refractory minerals, the pressurized hydrosynthesis and preparation, pressurized hydrohydrogen reduction and low-carbon metallurgy. In this paper, the development and characteristics of pressure hydrometallurgy technology are described, with emphasis on the research progress of clean production of alumina pressure hydrometallurgy, oxygen pressure leaching of sulfide ore and pressure hydrometallurgy of vanadium slag. Finally, the development prospect and direction of pressure hydrometallurgy technology in the future are prospected. [ABSTRACT FROM AUTHOR]

Abundant low-grade nickel sulfide ore reserves hold potential as nickel resources but are hindered by high magnesium silicate content, limiting efficient utilization. The authors investigated the possibility of extracting nickel from a low-grade ultramafic nickel sulfide concentrate into ferronickel alloy. The nickel extraction study involved thermal upgrading and physical separation. Thermal upgrading efficiently concentrated nickel values from ultramafic concentrate into ferronickel alloy, achieving over 90 pct extraction with more than 40 pct nickel grade and a characteristic particle size of d80=100 µm. The presence of magnesium silicate gangues in the concentrate adversely impacted the thermal extraction of nickel. Multiple thermal treatment variables have been studied to improve nickel extraction efficiency, including metallic iron addition rate, heating duration, temperature, additives, and atmosphere. The proposed solid-state thermal upgrading method avoided smelting of materials and generation of sulfur dioxide. Magnetic separation recovered approximately 85 pct of nickel in the thermal treatment products into a ferronickel concentrate at 20 pct nickel grade. [ABSTRACT FROM AUTHOR]

The research explores the impact of basicity on the softening and melting behaviors of limonite laterite nickel ore sinter. With the global decline of sulfide nickel ore resources, the extraction of nickel metal from laterite nickel ores has become a primary method. This study conducts a comprehensive experimental analysis and simulation of the behavioral characteristics of laterite nickel ore sinters and the properties of the soft melting zone to understand its key influencing factors and mechanisms in the blast furnace smelting process. Due to the unique composition of laterite nickel ore sinter, its softening zone position in the blast furnace is generally higher. Increasing the basicity can significantly improve the position and range of the softening zone, and when the basicity reaches 1.3, the permeability of the furnace material is optimal. Simultaneously, increasing the basicity can mitigate the adverse effects of the difficult‐to‐reduce and difficult‐to‐melt substance, chrompicotite, and its reduction products. [ABSTRACT FROM AUTHOR]

In this paper, the process of solid-state metalized reduction and magnetic separation was investigated for preparation of nickel–iron concentrate from a low-grade laterite nickel ore. The effects of reduction temperature, reduction time, amount of dosages, and magnetic field strength on grades and recoveries of nickel and iron were studied. The results showed that nickel–iron concentrate with a nickel grade of 7.32%, nickel recovery of 81.84%, iron grade of 78.74%, and iron recovery of 69.78% were obtained under the conditions of a reduction temperature of 1200 °C, reduction time of 120 min, calcium fluoride addition of 12%, ferric oxide addition of 10%, coal addition of 12%, and magnetic field strength of 170 kA/m. [ABSTRACT FROM AUTHOR]

The Corruption Eradication Commission (KPK) sniffed out potential tax evasion through a transfer pricing scheme on alleged illegal nickel ore export practices to China. KPK Deputy for Prevention and Monitoring Pahala Nainggolan said that his agency is currently reviewing if there are weaknesses in the nickel governance system. The system in question is the Coal Mineral System or Simbara, which was launched in March 2022. The population of this study is mining sector manufacturing companies listed on the Indonesia Stock Exchange (IDX) from the period 2020 -- 2023. Determination of samples in this study using the purposive sampling method. The number of samples used was 18 companies with 72 research units. The source of data in this study is taken from the company's published annual report. Testing in this study using E-Views 12 software. The results of the study based on the panel data regression analysis test showed that debt convenant and intangible assets had an effect on transfer pricing, while the size of the company and the bonus mechanism did not affect transfer pricing. Tax minimization is able to moderate the relationship between company size, debt convenant, intangible assets, and bonus mechanisms for transfer pricing. [ABSTRACT FROM AUTHOR]

Slag nikel is a by-product of nickel ore smelting through the pyrometallurgical process, which contains silica (> 50 %). This suggests that nickel slag, possessing pozzolanic properties, which potentially to be used as a binding material in construction projects dealing with low soil bearing capacity, such as soil improvement for road foundation. Pozzolanic reactions are greatly influenced by the chemical bonds formed between the binding material and the soil, causing mechanical characteristic changes in the soil. This study aims to examine the effect of adding nickel slag to soft soil based on changes in its physical, mechanical and chemical properties. Physical and mechanical property tests were conducted according to ASTM standards, while the changes in chemical structure in the soil were analyzed based on X-Ray Diffraction (XRD) test results. In this study, nickel slag percentages of 3, 6, 9 and 12 % were used based on the weight ratio of clay soil, at optimum water content (wopt). Furthermore, the test specimens were cured for 14, 28 and 56 days to observe the effect of time on the increase of crystal phases in each variation. The results showed that the presence of nickel slag in the soil can affect its physical and mechanical properties. The nickel slag content in the soil of 3, 6, 9 and 12 % reduces the plasticity index by 16.69, 12.02, 8.86 and 6.38 %, respectively. Meanwhile, the density values increased by 10.97, 11.27, 11.68 and 12.01 kN/m³, respectively. The changes in physical and mechanical properties can be explained by the XRD analysis results, showing changes in the spectrum curve and peak intensity of X-Ray Diffraction in the soil with the addition of nickel slag. This explanation clarifies the transformation of the soil's atomic structure from an amorphous state to a crystalline form, which is stabilized by nickel slag. [ABSTRACT FROM AUTHOR]

The article presents the results of obtaining a composite material by sintering nickel-containing raw materials mixed with carbon-containing materials, namely using coke and semi-coke. The sintering process was performed at a charge layer height of 240 mm and the temperature of the lower layer was T = 1200 °C. The results of the sieve analysis showed (a fraction of 10 mm) that the yield of a suitable composite material using coke was 68.3% and with semi-coke 67.0%. The average nickel and chromium content in the composite materials was 1.42% and 3.07%, accordingly. As a result of determining the strength characteristics of the obtained composite materials with various reducing agents by dropping from a height of 2 m onto a steel pallet, it was found that the obtained composite materials have high mechanical properties in terms of strength of 81% and 89.2%. The results of the elemental composition at the studied points and the thermal analysis of the studied composite material are presented. The mineralogical composition of the composite material is presented in the form of serpentine and nontronite, and the empty rock is made of quartz and talc. The activation energy of thermal analysis by the method of non-isothermal kinetics were calculated. The results of experiments on the production of composite materials from nickel-containing raw materials will be recommended for obtaining the optimal composition of composite materials at the stage of pilot tests and industrial development of the developed technology for processing nickel ores of the Republic of Kazakhstan. For the processing of nickel-poor nickel ores, it is of great importance to obtain optimal technological and technical and economic indicators that ensure low cost of nickel in the resulting product. [ABSTRACT FROM AUTHOR]

Nickel has excellent physicochemical properties and a wide range of applications, nickel resources are mainly found in nickel sulfide ores and nickel laterite ores, and nickel laterite ores are gradually becoming the main raw materials for nickel extraction. Due to the high water-content of nickel laterite ores, high temperature pre-treatment of the ores is usually required in the smelting process to remove hydroxylated water in the lattice of the ores and to prereduction of part of the metal, but this part of the hydroxylated water removal needs to consume a lot of energy and produce physical phase changes, which will affect the prereduction and leaching. However, the removal of this part of hydroxyl water needs to consume a large amount of energy, and produces physical phase changes, which will have an impact on the prereduction and leaching, so it is important to investigate the physical phase changes and kinetic conditions of the dehydroxylation process of nickel laterite ores for the subsequent processing operations. In this paper, the possible chemical reactions during the heating process of nickel laterite ore were simulated and calculated using thermodynamic analysis software, and the physical phase changes during the heating process of nickel laterite ore of silica-magnesium type were investigated using thermogravimetric-differential thermal analysis and XRD analysis, and nonisothermal kinetic experiments were carried out at five heating rates from room temperature to 1 400 °C. Three characteristic peaks were observed at 256.8, 582.8 and 823.0 °C, corresponding to the fuselage dehydroxylation process. The three characteristic peaks corresponding to the dehydroxylation of limonite, dehydroxylation of serpentine, and phase transformation of silicate minerals respectively. A nonisothermal kinetic model solution was used to determine the apparent activation energy and the finger front factor of the reaction. The activation energy of the serpentine dehydroxylation process was calculated by using the Flynn-Wall-Ozawa method and the Kissinger Akahira-Sunose method, and 30 commonly used mechanistic functions were fitted by using the Satava-Sestak method, and the eligible mechanistic functions were retained. The A1/3 function of the Avrami-Erofeev equation was determined to be consistent with the dehydroxylation process, and is integral form was G(α) = + - ln (1-α)] ³, which yielded the activation energy of the serpentine dehydroxylation reaction to be 258.71 kj/mol, lnA being 28.94, and the average linear correlation coefficient of 0.995 1. The serpentine dehydroxylation process is consistent with stochastic nucleation and subsequent growth of serpentines. The process is consistent with the stochastic nucleation and subsequent growth model. [ABSTRACT FROM AUTHOR]

In recent years, with the increasing demand for stainless steel and new energy nickel, the wet nickel extraction process from laterite nickel ore has been widely used, and the corresponding acid leaching residue piles of laterite nickel ore has also rapidly increased. It is urgent to scientifically consume and comprehensively utilize such solid waste. The comprehensive utilization of new technologies and equipment for the high content of sulfur and iron elements in acid leaching slag of laterite nickel ore has important theoretical and practical significance for the sustainable development of the laterite nickel ore wet metallurgical industry. The hydrometallurgical formation process, composition, and physical and chemical properties of laterite nickel ore acid leaching residue has been introduced. A systematic review was conducted on the direct treatment methods of laterite nickel ore acid leaching residue in tailings dam accumulation, underground pressure filtration backfilling, and deep-sea landfill. Valuable metal resources such as iron, chromium, aluminum, and rare earths were extracted and utilized, and the research progress in the comprehensive utilization technology for building materials such as diatomaceous earth, ceramic particles, and mineral fibers as well as the consumption in preparation of high value-added materials such as lithium battery electrodes and zeolites. It also looks forward to the development prospects of fluidized reduction roasting technology and equipment in reducing sulfur and improving iron content of laterite nickel ore acid leaching residue. [ABSTRACT FROM AUTHOR]

In anticipation of future demands, a comprehensive understanding of the chemical and mineralogical characteristics of nickel-bearing minerals is a prerequisite to devising effective nickel beneficiation methods. Of particular importance are markers in the mineralogy of the flotation concentrate that inform beneficiation strategies to improve concentrate grades, increasing both the marketability and cost of refining. In this work, a detailed characterization of a complex nickel sulfide flotation concentrate from a Western Australian deposit was carried out to determine the mode of occurrence and distribution of nickel and the associated gangue minerals, with the view of identifying prudent beneficiation strategies to improve concentrate grades. The concentrate was characterized via particle, chemical, and mineralogical techniques. Particle size analysis of the concentrate showed that it consisted predominantly of fine and ultra-fine particles (<20 μm), with the nickel value concentrated in the finer size fractions. Nickel mineralization in the ore (by quantitative X-ray diffraction) was found to be within pentlandite, violarite, millerite, and gersdorffite. The sulfide gangue was predominantly pyrrhotite, pyrite, chalcopyrite, sphalerite, arsenopyrite, and galena. Quantitative evaluation of minerals by scanning microscopy (QEMSCAN) analysis revealed that nickel minerals are at least 91% liberated, and the remaining portion (around 7%) is locked within binary iron (Fe) sulfides and 2% within complex minerals. Based on these findings, potential processing options, such as magnetic separation, gravity separation, and froth flotation, for recovering and upgrading nickel from this concentrate are discussed. Notably, with the significant presence of ultrafine/fine pyrrhotite content, averaging around 52% in the minus 38 µm fraction, novel flotation cells, including the Jameson cell, column flotation cells, and Reflux flotation cell (RFC), have been identified as potential candidates for fine/ultrafine pentlandite recovery. Overall, the characterization study conducted suggests that acquiring knowledge about the mineralogical characteristics of existing mineral concentrates can serve as a pathway to improving future concentrate grades. [ABSTRACT FROM AUTHOR]

This study was intended to investigate the effects of basicity and oxygen partial pressure on the distribution behavior of Ni in the nickel smelting process using nickel oxide ore, the raw material of nickel, among natural ores. Experiments were conducted in a vertical tube furnace using Fe-Ni metal and FeO-MgO-SiO2 ternary slag, which simulated the composition of natural ore. An equilibrium experiment was conducted to observe the distribution ratio of Ni, and thermodynamic data required for this experiment was calculated through Factsage. As a result, it was found that as the oxygen partial pressure increased, the Ni content in the slag increased linearly. The Ni content in the slag increased as the basicity moved away from 0.60. [ABSTRACT FROM AUTHOR]

In this study, we investigated a nickel laterite ore with Ni content of 1.56 wt% and a red mud with Fe content of 20.98 wt%, the main Ni-bearing mineral in the nickel laterite ore was nickel-lizardite, and the main Fe-bearing mineral in the red mud was hematite. A novel process of roasting and magnetic separation was purposed to extract nickel and iron from the nickel laterite ore and red mud. The nickel laterite ore, red mud, calcium chloride, and coke were mixed and put in a roaster for roasting, and the ferronickel concentrate was obtained from the roasted ore by magnetic separation. The results showed that a ferronickel concentrate with Ni content of 7.97 wt%, Fe content of 73.09 wt%, iron recovery of 76.87%, and nickel recovery of 90.28% was obtained under the optimal conditions: a mass ratio of m (nickel laterite ore): m (red mud) : m (coke) : m (calcium chloride) : of 0.6:0.4:0.2:0.1, a roasting temperature of 1373 K, a roasting time of 90 min, a grinding fineness of − 0.045 mm occupying 90%, and a magnetic field strength of 0.20 T. The main minerals in the ferronickel product were metallic Fe and FeNi. [ABSTRACT FROM AUTHOR]

In this study, the settling performance of lateritic nickel ores in the Counter Current Decantation (CCD) thickeners following the High-Pressure Acid Leaching (HPAL) process was investigated in detail. The samples used within the scope of the study were obtained from the overflow of the 2nd CCD thickener under the condition that Manisa-Gördes and Eskişehir-Karaçam lateritic nickel ores were fed to the plant at different times. A series of settling tests were performed for both ores using anionic, cationic, and nonionic flocculants of various ionicity and molecular weight. Sedimentation performance was evaluated based on parameters such as settling time, clarity, and compression. To determine the optimum conditions for the tests, a preliminary test was performed, and the pulp solids content was determined as 7% and the flocculant dosage as 850 g/t. According to the test results, nonionic and very low anionic flocculants gave better results. It was found that flocculation was negatively affected with increasing anionicity, and results could be obtained only with very low anionicity flocculants. It was determined that the settling rate was very fast with cationic flocculants, but the amount of compression was not favorable, especially for Gördes ore. However, it is envisaged that the amount of consumption can be reduced if cationic flocculants are used especially for Karaçam ore. When a comparison was made between the ores, similar results were obtained in general and only for Karaçam ore, thickener underflow density gave a successful result for all flocculant performances. On the other hand, it was concluded that variable ore structures and unstable process parameters influence the flocculant adsorption mechanisms and thus on the settling behavior. [ABSTRACT FROM AUTHOR]

We present a carbonation-assisted flotation method for nickel (Ni) separation from low-grade ultramafic ores. The high process economics of conventional flotation of low-grade ultramafic ores makes Ni unrecoverable on an industrial scale. Based on the fundamentals of CO2 sequestration in minerals, we carbonated a low-grade serpentine (lizardite) ore specimen under extreme conditions (185 °C, 15 MPa, and 24 h) and attained a conversion efficiency of serpentine to magnesite of 22% and 16% in the presence and absence of inorganic salts, respectively. Rhombohedral structures on carbonated particles detected using scanning electron microscopy suggested the formation of magnesite. We also found that Ni–Fe existed as sulfides, as confirmed by elemental mapping micrographs, and did not leach out as Ni2+ and Fe2+, as confirmed through carbonation supernatant analysis. Here, we introduced Denver cell froth flotation experiments after carbonation, which showed that the carbonated ore in the presence of inorganic salts had 29% higher Ni recovery and 0.15 wt% higher nickel grade than the uncarbonated ore. This study is the first to successfully show that the carbonation of serpentine containing nickel-bearing pentlandite leads to magnesite formation, does not lead to the dissolution of nickel sulphide, and enhances the nickel separation efficiency during froth flotation. This study paves the path forward for the integration of mineral carbonation in the processing of low-grade ultramafic nickel ores. [ABSTRACT FROM AUTHOR]

Rotary kiln-electric furnace (RKEF) technology accounts for 95 pct of the lateritic nickel ore processing. Coal is commonly used as fuel and reducing agent in the rotary kiln to produce solid reduction product which is then melted in the electric furnace. The use of coal in the process leads to the emission of approximately 70 tons of CO2 for every 1 ton of nickel in ferronickel or nickel pig iron product. One of the possible solutions for minimizing CO2 emission in the RKEF process is through the substitution of carbon-based fuel and reducing agent with hydrogen gas. This research focuses on experimental investigation on the reduction of saprolite nickel ore under hydrogen-argon atmosphere. The research was initiated by performing a thermodynamic simulation using FactSage 8.0 to preliminary evaluate the effects of different parameters on the reduction process. Reduction experiments of saprolite nickel ore were then carried out in a horizontal tube furnace with varying temperature (500 °C, 600 °C, 700 °C, 800 °C, and 900 °C), hydrogen gas composition (25 and 75 pct H2 in H2–Ar gas mixture), and reaction time (0.25 to 3 hours) to simulate the process in the rotary kiln. The solid reduction products were analyzed using ICP-MS, SEM-EDS, and XRD. The overall reduction extents in all conditions were also monitored by weight measurements of the samples before and after the reduction processes. Based on the weight changes, the reduction process was found to be significantly rapid so that it reached completion in 15 minutes. Each solid reduction product was then melted in a vertical tube furnace at 1550 °C for 2 hours under inert, argon atmosphere to simulate the process in the electric furnace. The metal product after melting had an average composition of 80.6 pct Fe and 8.3 pct Ni which is similar to commercially produced nickel pig iron. [ABSTRACT FROM AUTHOR]

The change of iron grade in the leaching residue and the leaching kinetics under normal pressure and pressure were examined. The pressure leaching of nickel and cobalt from a high iron and low grade laterite nickel ore in Indonesia with sulfuric acid was studied. The results show that under the conditions of acid/ore ratio of 260 kg/t, leaching temperature of 250 °C (corresponding to water vapor pressure of 4. 0 MPa), liquid volume/solid mass ratio of 3/1, stirring speed of 300 r/min, particle size of 100 mesh and reaction time of 1 h, the leaching rates of nickel, cobalt and iron are 98. 1 %, 98. 3% and 4. 7%, respectively, and the iron grade can reach 51. 3%. The leaching processes of nickel and cobalt under pressure and atmospheric pressure are in line with the shrinkage kernel model of interfacial chemical reaction control, and the activation energies of the reactions are 116 kj/mol and 91 kj/mol under pressure, respectively, and the activation energies of the reaction under atmospheric pressure are 41 kj/mol and 53 kj/mol, respectively. The leaching is mainly goethite under normal pressure, and chromite, magnetite and other mineral phases under high pressure. [ABSTRACT FROM AUTHOR]

The article presents the results of physicochemical studies of nickel ore and charges based on it for smelting nickel-containing ferroalloys. Using a derivatogram, the main phase transformations of nickel ore and mixtures with various carbon-containing reducing agents, such as coal and coke, are established. The activation energy of the processes occurring during the heat treatment of nickel ore and a mixture of nickel ore with various reducing agents by non-isothermal kinetics were determined. [ABSTRACT FROM AUTHOR]

The magnesium slag (magnesium nitrate hydrate Mg(NO3)2·6H2O) produced in the nitric acid leaching process of laterite nickel ore can be effectively recycled by thermal decomposition. To this end, this study placed great emphasis on disclosing the thermal decomposition mechanism of Mg(NO3)2·6H2O. Firstly, thermal decomposition paths of Mg(NO3)2·6H2O were revealed through Thermogravimetry-Mass Spectrometry, Differential Scanning Calorimetry and powder X-ray diffraction. It was found that the thermal decomposition of Mg(NO3)2·6H2O was a multistep endothermic reaction involving two dehydration stages and one denitration stage. The two dehydration stages were characterized by the evolution of H2O, with the formation of magnesium nitrate dihydrate and anhydrous magnesium nitrate. The denitration stage was characterized by the simultaneous evolution of O2 and NO2, with the formation of MgO. The conventional kinetic analysis was not suitable for describing such complex multistep reaction behaviour. Thus, the kinetic rate data (dα/dt-T) for the overall reaction were separated into those for three contributing stages by mathematical peak deconvolution. Then, the complete kinetic interpretations of the separated reaction stages for Mg(NO3)2·6H2O pyrolysis were achieved by the Friedman method and the master plots method. Finally, the original experimental α-T curves were successfully simulated using the resulting kinetic triplets. [ABSTRACT FROM AUTHOR]

There is a variation in nickel content produced by PT. Aneka Tambang Tbk Site Pakal with the needs of the processing industry so that the blending method needs to be applied. Blending is the process of mixing two or more materials that have different qualities to get the right mixture. In the blending process, it must meet the specific ore according to the needs of the processing plant. The results of the XRF analysis on the stockpile Sosolat, Bicoli, Maba, Mafia, Sangaji, Roomstock Harmony, Resampling Sangaji were respectively 2.26%, 1.61%, 1.48%, 1.35%, 1.32%, 1.53%, and 1.60%. The results of theoretical simulations and actual blending in the field obtained factory quality of 1.75%, Buana Jaya barge with simulated Ni content of 1.87% and realized Ni content of 1.76%, Bukit Emas barge with simulated Ni content of 1.83% and realized Ni content of 1.90, TGH barge with simulated Ni content of 1.85% and realized Ni content of 1.76%, Ilir Jaya barge with simulated Ni content of 1.87% and real Ni content sai is 1.85%, the DBS 3029 barge with a simulated Ni content of 1.88% and a realized Ni content of 1.78%. [ABSTRACT FROM AUTHOR]

The contradiction between the supply and demand of nickel resources is intensifying, and it is urgent to develop new processing and smelting processes for laterite nickel ore. Gas based smelting with H2 and CH4 as reductants is of great significance to solve the "double carbon" problem faced by the traditional metallurgical industry. Taking low-grade laterite nickel ore as the research object, CH4 as the reductant and elemental sulfur as the additive, under the conditions of different reduction temperature, reduction time, gas concentration and additive dosage, this paper discusses the reduction behavior of CH4 and iron nickel oxide in laterite nickel ore. Combined with XRD, SEM-EDS, gas analysis and other characterization methods, the phase and morphology of laterite nickel ore and its reduction products were deeply analyzed. Results surface: under the conditions of reduction temperature 800°C, reduction time 60 min, CH4 concentration 20%, elemental sulfur dosage 4%, the metallization rate of nickel and iron in the reduction product can reach 98.01% and 8.44%, respectively. Nickel oxide is almost completely reduced to nickel, and most of iron is reduced to low-price iron oxide. In the reduction process, the amorphous silicate recrystallizes into magnesium olivine phase in the reduction process. It hinders further reduction of nickel. According to SEM-EDS analysis, some metal iron and elemental sulfur generate FeS around the iron oxide region, which hinders the contact between reducing gas and FeO. Therefore, the reduction of iron is inhibited and the iron oxide content increases. It promoted the selective reduction of nickel. [ABSTRACT FROM AUTHOR]

Under the background of carbon peaking and carbon neutrality, compared with a traditional carbon thermal reduction to produce nickel, gas-based reduction has outstanding advantages in efficiency and carbon reduction. However, there are few studies on gas-based reduction at present. This article explores the reduction behavior of methane on laterite nickel ore. The effects of different reaction temperatures, reaction times and gas concentrations on the reduction reaction were studied. The phase and morphology of laterite nickel ore and its calcined products were analyzed by XRD, SEM-EDS and gas chromatography. The results show that when the reduction temperature is 900 °C, the reduction time is 60 min, and the concentration of CH4 is 50%, a concentrate with a nickel grade of 3.06% and a recovery of 52.09% can be obtained. After analysis, the reason for the low nickel grade and recovery rate in the concentrate is, on the one hand, due to the incomplete reduction of NiO, and a large amount of nickel still exists in the silicate in the tailings; on the other hand, it is due to the fine grain size of the partially reduced nickel iron alloy, which is lost in the tailings and filtrate. [ABSTRACT FROM AUTHOR]

Nickel is widely used in industrial processes and plays a crucial role in many applications. However, most of the nickel resource mainly exists as nickel oxide in laterite nickel ore with complex composition, resulting in difficulty in upgrading the nickel content using physical separation methods. In this study, high-grade ferronickel concentrates were obtained through a carbothermal reduction and magnetic separation using laterite nickel ore and anthracite as raw materials. The effects of different types of additives (CaF2, Na2SO4, and H3BO3), carbon ratio (the molar ratio of oxygen atoms in the laterite nickel ore to carbon atoms in anthracite), and grinding time on the recoveries and grades of ferronickel concentrates were experimentally investigated, along with the microstructure and chemical composition of the products. CaF2 was proved to be the primary active additive in the aggregation and growth of the ferronickel particles and the improvement of the grade of the product. Under the optimal conditions of CaF2 addition of 9.85 wt%, carbon ratio of 1.4, and grinding time of 240 s, high-grade magnetically separable ferronickel concentrate with nickel grade 8.93 wt% and iron grade 63.96 wt% was successfully prepared. This work presents a practical method for the highly efficient recovery and utilization of iron and nickel from low-grade laterite nickel ore, contributing to the development of strategies for the sustainable extraction and utilization of nickel resources. [ABSTRACT FROM AUTHOR]

This paper investigates the synergistic extraction performance of Scandium using a mixture of Cyanex572 and Cyanex923 in sulfuric acid medium. The results show that the best synergistic effect is achieved when the pH value of the aqueous phase is 2 and the mole fraction of Cyanex572 is 0.5, with a synergy coefficient value R of 4.78. In addition, the extraction mechanism of this synergistic system is discussed, and the extracted complex is determined to be [Sc(SO4)0.5(HL2)2B2] by slope analysis. The loaded Scandium can be stripped within two times by 2 mol/L sulfuric acid to obtain a stripping efficiency of 99.4 %. Finally, this synergistic system was applied to extract Scandium, demonstrating the potential application in separation of Scandium from the leachate of laterite nickel ore. [ABSTRACT FROM AUTHOR]

Attempts have been made to extract nickel from ores and nickel-containing wastes using the chlorination method. However, the use of gaseous chlorinating agents is limited due to their toxicity. High-temperature chlorination of nickel oxide using calcium chloride is analyzed in this study. The volatilization percentage is positively correlated to temperature and CaCl2 dosage and negatively correlated to oxygen partial pressure. The apparent activation energy is calculated to be 142.91 kJ/mol, between 1173 K and 1323 K, which suggests that the high-temperature chlorination of nickel oxide using calcium chloride is controlled by a chemical reaction. [ABSTRACT FROM AUTHOR]

This paper delves into the intricate dynamics of international law and dispute resolution within the context of renewable energy development, focusing on Indonesia's downstreaming of nickel ores. As renewable energy initiatives gain prominence globally, the demand for essential minerals like nickel increases, prompting nations like Indonesia to explore downstreaming processes. However, this transition presents complex legal challenges, including international trade agreements, environmental regulations, and indigenous rights. Through a comprehensive review of relevant literature and case studies, this study analyzes Indonesia's approach to nickel ore downstreaming and its implications for international law and dispute resolution mechanisms. Additionally, it examines the role of international organizations, such as the World Trade Organization (WTO) and the United Nations Commission on International Trade Law (UNCITRAL), in resolving disputes arising from renewable energy projects. By synthesizing legal frameworks, environmental concerns, and socio-economic factors, this paper offers insights into navigating the legal complexities of renewable energy development, with a focus on Indonesia's nickel industry. Ultimately, the findings contribute to the discourse on sustainable resource management and the role of international law in facilitating equitable and environmentally responsible energy transitions.

Dewatering unit operations are essential steps in mineral processing routes to obtain materials with high levels of solid content (60-70 wt.%). Polymers have been used for coagulation and flocculation in wastewater treatment for many years, and its application is mostly based on the ad-sorption mechanisms. In the case of fine nickel ore tailings, wastewaters typically contain large amounts of particles within microscale (d50 = 9.5 µm). The use of flocculant polymers, mostly poly-acrylamides, acts to remove colloids from these effluents. Environmentally friendly natural polymers, such as chitosan and humic acid, when used combined can be a highly effective reagent for the treatment of these tailings. Therefore, the purpose of this study is to evaluate the use of these natural polymers in the treatment of wastewater containing colloidal material to adequate the fine particles content to less than 50 NTU, satisfying environmental standards. Particle removal efficiency was calculated based on turbidity on wastewater as well as on thickener overflow. For fine 24 nickel tailings containing 2.15% (wt./vl.), a mixture of chitosan/humic acid of 24.9/6.3 g/t at pH=6.7 25 achieved a sedimentation of 95 wt.%. The turbidity was reduced to 40 NTU, motivating the use of 26 this technique to adequate wastewater to water reuse. [ABSTRACT FROM AUTHOR]

At present, scholars mainly study the relationship between nanobubbles and useful minerals, often ignoring the influence of bubbles on fine gangue minerals. When selecting nickel sulfide ore, scholars often faced with mudded and irrepressible serpentine, which seriously affects the quality of the concentrate. This mudded serpentine mineral often enters foam products with bubbles. In this study, the role of nanobubbles in the flotation behavior of hydrophilic serpentine was examined. Nanobubbles were successfully prepared via ultrasonic cavitation, with sizes ranging from 50 to 250 nm. The size and number of bubbles produced at 1 min and 2 min of sonication were significantly better than those of the prolonged test group, and it was found that longer sonication time did not produce better results. The stability of the nanobubbles produced via ultrasound was studied, and it was found that the nanobubbles were stable, with no change in size and only a slight decrease in number as the resting time increased. Nanobubbles were introduced into serpentine flotation, we found that the presence of nanobubbles significantly reduced the flotation recovery of serpentine. The presence of nanobubbles reduced the froth entrainment rate of microfine-grained serpentine, which in turn reduced its flotation rate. In the depressant group trials, it was found that the nanobubbles also reduced the amount of depressant. In short, the presence of nanobubbles can prevent the floating of fine hydrophilic gangues during flotation. [ABSTRACT FROM AUTHOR]

Most nickel laterite smelting to produce ferronickel is carried out using an AC-arc furnace. Although the DC-arc furnace is advantageous in the smelting of fine ore, it is rarely used for nickel laterite. In this work, the effects of slag basicity and stoichiometry of reductant addition during smelting of low-grade saprolitic nickel ore on nickel content and nickel recovery, yield, and phases of the slag were studied in detail. The smelting process was conducted in a laboratory DC-arc furnace with a a single electrode of 30 cm diameter. A 5 kg of low-grade saprolitic nickel ore (1.92 Ni-12.97 Fe), some coke as reductant, and some limestone as flux were smelted in a DC-arc furnace for about one hour. The pouring temperature of hot metal and slag was 1400-1500 °C. The basicity of the quaternary slag of 0.8 and the stoichiometric carbon of 0.8 of the reductant resulted in an optimum smelting process of nickel ore in a DC-arc furnace, producing ferronickel with a Ni content of 14.59% with 92.26% recovery. [ABSTRACT FROM AUTHOR]

Strict environmental regulations have made on many industrial sectors to try and reduce CO2 gas production, including the nickel and ferronickel manufacturing industries. One of the promising technologies in reducing CO2 emissions is carbothermic reduction using a lower operating temperature than smelting process. This study aims to study the effects of adding and laying reductant (coal) on composite briquette. By using the same C/O molar ratio, this research tries to study the effects of inner and outer coal on the carbothermic reduction of laterite nickel ore. The carbothermal reduction process was carried out at 700 °C for 2 h and then followed by heating at 1400 °C for 6 h. Then, the ferronickel was separated from the impurities by magnetic separation. Several tests and calculations were carried out to assess process performance, such as energy dispersive X-ray, scanning electron microscope, X-ray diffractometer, calculation of nickel recovery, calculation of selectivity factor, and calculation of separation efficiency. The result showed that inner and outer coal in the carbothermic reduction process of laterite nickel ore can affect the selectivity performance of nickel. The best nickel recovery (93%) was obtained when using 70% inner coal and 30% outer coal. On the other hand, the best nickel content (13.99%) was achieved when using 90% inner coal and 10% outer coal. The ferronickel product obtained from this process can be applied as a raw material in stainless steel making or further processed into nickel sulfate powder. [ABSTRACT FROM AUTHOR]

This study aimed to increase the recovery efficiency of nickel metal and reduce smelting energy consumption by analyzing the effect of adding B2O3 on the melting characteristics of nickel flash melting slag and the separation of slag and matte. In particular, thermodynamic analysis and high-temperature experimental investigations showed that adding B2O3 decreased the melting temperature of the slag system and enhanced the slag flow characteristics. Furthermore, the primary process parameters required for slag and nickel matte separation were predicted and optimized using single-factor experiments and the response surface method. The degree of the effect on the slag-matte separation was as follows: temperature > MgO content > FeO/SiO2 > B2O3 content. The optimal separation conditions were settling temperature 1300°C, MgO content 8 wt.%, FeO/SiO2 1.55, and B2O3 content 2.4 wt.%. The mechanism demonstrated that adding B2O3 could significantly reduce the impact of low-quality nickel ore on smelting. Moreover, the separation and recovery of the matte and slag were both successful. Findings indicate that an efficient way to optimize the smelting process is adding B2O3, which is expected to improve the development of metal recovery technologies. [ABSTRACT FROM AUTHOR]

The development of the electric vehicle industry has increased the need for batteries. The NMC (Nickel Manganese Cobalt) battery is one type with superior properties. The nickel used to manufacture NMC batteries is nickel (II) sulfate hexahydrate (NiSO4·6H2O) compounds. A mixed sulfate precipitate should be synthesized to obtain it. Thus, nickel ore has been first smelted in the Mini Blast Furnace, after which the smelted and cooled Nickel Pig Iron (NPI) has been leached into a solution. This study has aimed to analyze the influence of agitation speed and particle size of NPI in the leaching process of mixed sulfate precipitate. The leaching process has used a 2M H2SO4. The leaching temperature is set at 90 °C for 6 hours with agitation speeds of 100, 200, and 300 rpm and particle sizes of -50 µm, +50 -80 µm, and +80 -112 µm. Next, the precipitation process has been carried out by using NaOH solution. Next, the crystallization process has been conducted to eliminate water in the solution and produce powder. The best nickel extraction has been obtained at a particle size of -50 µm at 98.19%. [ABSTRACT FROM AUTHOR]

Large amounts of solid waste-spent cathode carbon (SCC) was produced in aluminum electrolysis process. At present, landfill and storage methods are widely used, which will not only cause great harm to the environment, but also cause a lot of waste of resources. Nickel and iron were recovered from laterite nickel ore by reduction roasting-magnetic separation using SCC as reducing agent. The fluorine in SCC was fixed in roasted ore by adding CaO. The feasibility of the method was verified by thermodynamic analysis and experiments, and the optimum conditions for CaO addition were determined. The recovery of nickel and iron reached 91.23% and 89.63% respectively when the addition of SCC was 14 wt.% and CaO was 8 wt.%. Adding 8 wt.% CaO under the condition of SCC as reducing agent can change the viscosity of roasted ore and promote the aggregation of ferronickel particles. The concentration of soluble F? in roasted ore was reduced and fixed in roasted ore in the form of insoluble calcium fluoride. Under the condition of adding 8 wt.% CaO, the fluorine fixation rate was 95.99%, and the concentration of F? in roasted ore was only 31 mg·L-1. [ABSTRACT FROM AUTHOR]