Dry Separation Research Articles

Renewable Distillation of Spent Nuclear Fuel

Nuclear waste is one of the most important environmental problems of nuclear power plants. A novel renewable distillation method has been proposed for the direct on-site recycling of spent nuclear fuel and the separation of its valuable components from fissile isotopes, which is especially applicable for reactors using liquid fuels. This dry separation technique can be applied in two single, parallel total-reflux columns with integrated separation stages for chlorinated nuclear waste. According to theoretical calculations, high separation accuracy of the UCl4-NpCl4, PuCl3-UCl3, CmCl3-SmCl3, and EuCl3-CsCl fractions could be achieved using twenty-six separation stages and five total-reflux repetitions, demonstrating the high efficiency of the method proposed. A scheme of the future pyroprocessing separation plant is also presented.

Judicious combinations of gravity, magnetic, electrostatic separators and microwave heat energy on recovery of ilmenite from Humma lean grade beach placer deposit

Microwave heating is an eco-friendly and novel technique for sintering and heating minerals and materials as it has several advantages in terms of phase transformation, energy efficiency, enhancing speed, process simplicity, improved properties. Such heating provides the composite materials to absorb electromagnetic energy volumetrically and transform into heat and produces larger densities as compared to conventional heating. This study focuses on two main objectives: the recovery of ilmenite through a strategic combination of mineral processing equipment, including a spiral concentrator, followed by magnetic and electrostatic separation, and the enhancement of ilmenite concentrate using microwave heat energy on a cleaner magnetic product, followed by electrostatic separation. Continuous magnetic separation results indicate that among the dry high-intensity belt magnetic separator, box mag wet high-intensity magnetic separator and dry rare earth drum magnetic separators, the rare earth magnetic separator yielded the highest quality product. The application of microwave heat energy before the rare earth drum magnetic separator at 1.4 T, followed by high-tension separation, produced the best grade of ilmenite. The magnetic product obtained after microwave treatment contained 98.6% ilmenite, which was further upgraded to a 99.6% ilmenite concentrate through high-tension separation. Therefore, it is recommended that an effective combination of gravity separation, microwave heat energy, rare earth drum dry magnetic separation and high-tension separation be employed to achieve the highest grade of ilmenite concentrate.

Kinetic study of dry magnetic separation based on Gauss-Maxwell magnetic stress tensor: A 3D finite element method (FEM)

In this paper, two artificial magnetic particles (1#, 2#) with known magnetic parameters were taken as the objects, a finite element model based on Gauss’s law was established for the calculation of the transient Maxwell magnetic stress tensor on the surfaces of particles and kinetic study, a high-speed camera was used to obtain the motion behaviors of magnetic particles in comparison with the simulation. According to the results of multiple simulation-experiment comparisons, the motion behaviors of magnetic particles in the finite element simulation were consistent with experimental phenomena under the identical conditions, indicated that the accuracy of the model is reliable. In the comparison of two kinds of magnetic force calculations, the magnetic force FM based on the Gaussian formula had a similar tendency to FD based on the kinetic calculations, and since the FM was obtained by converting the surface tension of particles, it more accurately reflected the overall magnetic force and magnetic torque acting on the particles. Kinetic analysis showed that the magnetic force acting on a particle was strictly dependent on its magnetization, dynamic and non-uniform magnetization caused the magnetic particle to be subjected to magnetic force and magnetic torque in the non-uniform magnetic field, resulting in displacements and flips. In addition, compared to the particle release attitude, the influence of the distribution of magnetic substance and the particle’s release position on the displacement was particularly significant. The 3D finite element model established for dry magnetic separation can be further used for the study of dynamic, non-uniform magnetization and the force of magnetic particle or grain groups, which is of certain significance for the kinetic study of magnetic separation and improving research of magnetic separation equipment.

Size fraction characterisation of highly-calcareous and siliceous fly ashes

The properties of coal fly ash vary significantly depending on factors such as coal type, combustion conditions, and flue gas emission reduction methods. This study investigates the influence of particle size fractionation on the chemical composition, mineralogical structure, and thermal behaviour of two types of fly ash: high calcium ash derived from lignite (S1) and silica-rich ash from bituminous coal (S2). Dry aerodynamic separation was used to obtain distinct size fractions, which were then subjected to a comprehensive characterisation including X-ray fluorescence, X-ray diffraction, scanning electron microscopy, and thermal analysis. The results reveal notable differences between the S1 and S2 ashes and between their size fractions. The finer fractions (< 20 μm) of S1 showed an increased calcium and sulphur content, while the coarser fractions (> 100 μm) contained more silica and alumina. The S2 ash exhibited a higher overall silica content, with alkali metals concentrated in finer fractions. Thermal analysis demonstrated distinct behaviours for each type and fraction of ash. Fine fractions of S1 ash showed SO2 emission at elevated temperatures, while S2 ash exhibited greater CO2 gas emission. After thermal treatment, the recrystallisation of the glassy phase was observed for S1, while the S2 ashes were more prone to melting and agglomeration. The study highlights the potential for the customised utilisation of specific ash fractions in various applications, such as geopolymer synthesis, adsorbent materials, and refractory products. This comprehensive characterisation contributes to a better understanding of fly ash properties and their dependence on particle size, providing valuable insights to optimise fly ash utilisation in various industries. The findings suggest strategies for a more efficient use of fly ash resources, particularly relevant in the context of decreasing fly ash availability due to the phase-out of coal power plants.

Mechanism analysis of enhanced desulfurization of pulverized coal through high-gradient magnetic separation with microwave radiation

Dry high gradient magnetic separation technology is a low-carbon green technology. It can be embedded in a power plant to remove coal pyrite with a high-efficiency magnetic separator and remarkable magnetic properties difference between coal pyrite and coal matrix. This study selected the microwave radiation method to improve the magnetic properties difference and carried out a desulfurization experiment with a self-developed high-gradient permanent magnetic separator using the tapered iron auxiliary magnetic pole. The results demonstrate that the pyrite content and specific magnetic susceptibility increase with the decrease in particle size. The desulfurization rate did not change significantly at 25 °C. The coal sample began to appear in the thermal reaction at 450 °C, and the pyrite can become a strong magnetic property pyrrhotite. The desulfurization rate can achieve 58.70 % at 700 °C, and is equivalent to the wet washing index, due to the supply of high magnetic field force. The dynamic characteristic response of magnetic particles becomes more obvious with short time adsorption, and the probability of carrying non-magnetic particles is reduced. This study demonstrates that the high-gradient magnetic separation technology of pulverized coal enhanced by microwave irradiation is feasible.

The influence of selected grain size fractions of coal fly ash on properties of clay-cement mortars used for the flood levees construction

This study examines the influence of different grain size fractions of coal fly ash on the properties of clay-cement mortars used in flood levee construction. Dry aerodynamic separation and mesh sieving were used to obtain ultrafine, fine, and medium fractions of high-calcium and silica fly ash. The experimental results reveal that the rheological properties of fresh mortars are significantly influenced by these fractions. High-calcium fly ash mortars exhibit high reactivity and rapid increase in viscosity, with finer fractions showing the highest reactivity. Silica ashes show increased reactivity in the later stages of suspension hardening. Their spherical shape contributes to reducing internal friction during flow in initial technological operations. Furthermore, the compressive strength of hardened mortars improves as the particle size decreases for both ashes, resulting in a dense and uniform microstructure. The separation and fractionation of fly ashes contribute to the obtaining of fractions that influence the parameters of clay-cement suspension application on different scales. The results show the potential benefits of ash separation, which can bring advantages in terms of economic viability, engineering performance, and ecological sustainability.

Enhanced Recovery of Magnetic Materials from Fly Ash Using Spiral Dry Magnetic Separation Technique

Enhanced Recovery of Magnetic Materials from Fly Ash Using Spiral Dry Magnetic Separation Technique

Utilization of Sengon Wood Sawdust as Bio-Pellet Feedstock: Characteristics, Potential, and Feasibility for Renewable Energy

The pellet-making process involves stages of drying, compaction, cooling, and size separation. Considering that Indonesia has great potential for biomass supply, this research aims to identify the characteristics of bio-pellets produced from sengon wood sawdust based on the pellet standard SNI8675:2018. The results showed that the highest calorific value at the Dry Basis (DB) condition was 4703 Kcal/kg, meeting national and international standards. The moisture content in the As Received (AR) condition was recorded at 10.36%, while the lowest ash content was 1.72%. The highest combustion rate was found in sample 3, with a value of 0.174 gr/min, indicating good combustion performance. The utilization of sengon wood sawdust as bio-pellets can be an efficient and environmentally friendly renewable energy solution, and has the potential to be further developed to support diversification and national energy security.

INVESTIGATION OF USAGE OPPORTUNITIES OF DIFFERENT PROPORTIONS OF WHEY AND CHIA SEED FLOUR IN BUTTERMILK

In this study, it was aimed to obtain a functional beverage with high nutritional value by using whey and chia seed flour in the production of buttermilk. In addition to its high nutritional value, while preventing whey from causing environmental pollution as a waste material, it is aimed to obtain a new dietary product with chia seed flour containing 34-40g fiber per 100g, antioxidant, omega-3 fatty acid and rich protein content. Experimental buttermilk samples were prepared by adding whey (PAS) and chia seed flour at different rates. K (control group), K2 (%1 Chia seed meal), K3 (%0,5 Chia seed meal), Group 1 (25% Whey + %1 Chia seed meal), Group 2 (25% Whey + %0,5 Chia seed meal), 3. Group (50% Whey + %1 Chia seed meal), 4.Experimental groups prepared as a group (50% Whey + %0,5 Chia seed flour) were kept at +4 ̊C and their physical, chemical and sensory properties were examined on the 1st, 3rd, 5th, 7th and 14th days. In the experimental buttermilk samples we researched, the use of whey and chia seed flour was found to have a significant effect on psychrophilic bacteria count (log cfu/ml), coliform group bacteria (log cfu/ml), yeast-mold count (log cfu/ml), lactobacil spp. (log cfu/ml) and lactococ spp. (log cfu/ml), pH, acidity (lactic acid), water-soluble dry matter (%), serum separation (%), color values (L*, a*, b*) and sensory properties (p

Study on separation of 6–0 mm low rank high sulfur lignite by FGX dry separation bed

ABSTRACT Coal is an essential primary energy for the national economy and people’s livelihood. In recent years, with the rapid growth of the consumption of high-quality coal resources, Lignite with a low degree of metamorphism has been extensively exploited and utilized. In this paper, desulfurization and ash reduction treatment of 6–0 mm fine-grade low-grade high-sulfur Lignite was carried out using a FGX dry separation bed (FGX FGX compound dry separation bed). The migration and distribution of differentiated density particles in the bed under the action of cascade air flow were mainly studied, and the influence of vibration intensity (amplitude and frequency) on the separation effect of fine-grade low-grade high-sulfur Lignite was explored. At the same time, the material distribution characteristics of each section in the direction of the discharge edge of the bed were systematically analyzed, the material distribution area of the bed was determined, the optimal operating parameters (A = 2.8 mm, f = 26 Hz, V = 2.29 m/s) were obtained, and the sorting test was carried out under the optimal parameter conditions. The test results show that when the vibration frequency f = 26 Hz, the sulfur segregation degree of bedding materials reaches the maximum Ss = 0.36, and the sulfur content of materials in I, II, and III regions is 0.85%, 5.47%, and 18.78%, respectively. The stratification effect of bedding materials is the best. When A = 2.8 mm, the material sulfur segregation reaches the minimum value of Ss = 0.28, and the average sulfur content of materials in I, II, and III regions is 0.78%, 5.46% and 18.27%, the material is stratified according to density. When the airflow rate is 2.55 m/s. The stratification effect of bed material is best according to density. The clean coal yield is 69.87%, and the sulfur content is 0.98%. The gangue yield is 30.13%, and the sulfur content is 18.66%. The Ep value of energy deviation is 0.11 g/cm3, which realizes high precision dry desulfurization and upgrading fine-grade, low-grade, and high sulfur lignite.

Comparative processing studies of the Arkachan deposit gold-bearing ores using dry separation and classical wet gravity separation methods

Comparative processing studies of the Arkachan deposit gold-bearing ores using dry separation and classical wet gravity separation methods

Iron Removal from Low-Grade Pyrophyllite Ore by Microwave Irradiation and Dry Magnetic Separation

Owing to its unique properties, pyrophyllite is an economical alternative to many minerals in different applications. The presence of iron-bearing minerals in Saudi pyrophyllite hampers its industrial uses. The aim of this study was to examine the removal of iron from Saudi low-grade pyrophyllite ore using two approaches. The first approach involves dry high-intensity magnetic separation, whereas the second approach involves microwave pretreatment of the ore before dry magnetic separation. For the first approach, the studied operating parameters were roll speed; feed rate, field intensity, and feed particle size. For the alternative approach, microwave treatment followed by dry magnetic separation, the microwave irradiation time and the magnetic field intensity were studied. The results show that the combined microwave treatment and dry separation method could provide high-purity pyrophyllite for filler industries. Microwave irradiation for 30 min was optimal to change impurity phases (i.e., pyrite, hematite) into ferromagnetic phases in microwave-treated pyrophyllite samples. At a magnetic field intensity of 2000 Gauss, the 30 min microwave-irradiated pyrophyllite sample achieved an iron recovery of 11.2% in non-magnetic fractions, with a removal efficiency of 89% with an alumina recovery of 91.31%.

Thermal Studies of Fractionated Lignite and Brown Coal Fly Ashes.

Coal fly ash (CFA), a by-product of coal combustion, is a valuable raw material for various applications. However, the heterogeneous nature of the composition and properties of CFA provides challenges to its effective usage and utilisation. This study investigates the thermal behaviour of the fly ashes of lignite (FA1) and brown coal (FA2) and their fractions obtained by dry aerodynamic separation. Thermal analysis techniques, including thermogravimetry (TG), differential scanning calorimetry (DSC), and evolved gas analysis (EGA), were used to characterise the behaviour of the fly ash fractions while heating up to 1250 °C. The results reveal distinct differences in the thermal behaviour between ash types and among their different size fractions. For the FA1 ashes, the concentration of calcium-rich compounds and the level of recrystallisation at 950 °C increased with the decrease in particle size. The most abundant detected newly formed minerals were anhydrite, gehlenite, and anorthite, while coarser fractions were rich in quartz and mullite. For the FA2 ashes, the temperature of the onset of melting and agglomeration decreased with decreasing particle size and was already observed at 995 °C. Coarser fractions mostly remain unchanged, with a slight increase in quartz, mullite, and hematite content. Recrystallisation takes place in less extension compared to the FA1 ashes. The findings demonstrate that the aerodynamic separation of fly ashes into different size fractions can produce materials with varied thermal properties and reactivity, which can be used for specific applications. This study highlights the importance of thermal analysis in characterising fly ash properties and understanding their potential for utilisation in various applications involving thermal treatment or exposure to high-temperature conditions. Further research on advanced separation techniques and the in-depth characterisation of fly ash fractions is necessary to obtain materials with desired thermal properties and identify their most beneficial applications.

Study on water transfer characteristics and desulfurization effect during the separation of fine low rank lignite in the dry dense medium fluidized bed

Coal is an important support for the development of the national economy. Lignite has high utilization value. This paper utilizes a dry dense medium fluidized bed for separation of low rank high sulfur lignite across the size range of 6–0 mm. The study focuses on the spatial diffusion and transfer characteristics of material moisture in the fluidized bed, systematically analyzes the influence of material moisture on the bed fluidization characteristics and the bed density spatial uniform stability, explores the diffusion and separation characteristics of the material in the bed, and determines the material separation time domain. The experimental results indicate that when t = 60 s, the high concentration area of the whole bed is distributed in the center, and the low concentration area is distributed in the side wall At when t = 360 s, the high concentration area of the upper bed is distributed near the side wall, and the high concentration area of the middle and lower layers are distributed in the center of the bed. At t = 420 s, the high concentration area in the upper layer gradually disappears, and the separation of high and low-density particles is completed in the middle layer, achieving stratification. When the bed layer moisture content is 0.5 % and the air flow is 16.3 cm/s, the bed pressure drop tends to stabilize, and the bed fluidization effect is better, reaching its peak moisture content. The fluctuation in bed layer spatial density distribution is significant, especially in the central area of the upper layer (within the circular area 0 ≤ R ≤ 3 cm), where the density distribution fluctuation is most pronounced, with an average density of 1.67 g/cm3. The fluctuation amplitude of the middle bed density is relatively low, with an average density of 1.65 g/cm3. The fluctuation amplitude of the lower bed density is the smallest, with an average density of 1.53 g/cm3. When t = 0–120 s, the ash content of each layer along the bed height is close to the raw coal, which belongs to the material diffusion distribution time domain. When t = 120–240 s, the material is stratified locally, which belongs to the material initial stratification time domain. When t = 240–420 s, the high and low density particles achieve orderly stratification, which belongs to the material sorting time domain The results show that the clean coal yield was 74.68 %, sulfur content is 0.98 %, ash content is 9.96 %, gangue yield is 25.32 %, sulfur content is 18.69 %, ash content is 58.32 %, Ep is 0.65 g/cm3. The high-precision dry separation of fine grained low rank high sulfur lignite was realized.

Effect of vibration and airflow on separation of 6–1 mm fine coal in compound dry separation bed

The segregation behaviour of solid particles are affected by airflow and vibration in a compound dry separation bed. The distribution characteristics of airflow field on the bed surface have been systematically investigated by a novel method of regional air distribution, and the movement and segregation behavior of fine coal particles have been observed under different gas velocity. Meanwhile, the spatial distribution characteristics and ash variation of fine coal particles during the process of segregation and stratification were analyzed. The obtained results show that the airflow velocity of the bed showed a zonal air distribution characteristic of gradual decrease from the separation area to the clean coal section and the gangue section. The segregation and stratification of particles in the Y-axis and Z-axis directions of the bed surface can be enhanced by vibration. When the vibration frequency is 34 Hz, the probable error (E) is 0.08 g/cm3. The bed inclination and the bed grid height have a certain influence on the segregation behavior of fine coal.

Effect of eddy currents on metal fine particles in high gradient magnetic separation using a superconducting magnet

Abstract Dry high gradient magnetic separation is one of the key technologies expected in removing magnetic metal fine particles as contaminations in the production process of various powders. However, the effect of eddy currents on such metal fine particles in dry high gradient magnetic separation has not been adequately explored in previous research. In order to understand this phenomenon more comprehensively, we conducted particle trajectory simulations using a finite element analysis with numerical methods and actual magnetic separation experiments to investigate the influence of eddy currents on magnetic separation efficiency. The results show that for both paramagnetic and diamagnetic metal particles, eddy currents can favourably influence the capture efficiency. Furthermore, these effects depend on the particle size, electrical conductivity, and the rate of change in the magnetic field. Therefore, by taking eddy currents into account, magnetic separation systems can be better optimized and their performance further improved.

Prediction of separation density of pulsed fluidized bed based on bidisperse particle characteristics

ABSTRACT Fluidized bed technology plays a vital role in petroleum, chemical, and coal separation. The dry separation of coarse coals with a particle size of >6 mm has been efficiently achieved using the fluidized bed. However, for fine coal with a particle size of 6–1 mm, ordinary fluidized bed technology is unable to effectively separate it. In light of this issue, the present study incorporates airflow vibration energy into conventional fluidized beds, with a specific focus on the separation process of fine coal. The investigation explores the variation pattern of separation density and delves deep into the influencing factors affecting coal preparation through bed density. A theoretical model for separation density is established based on the characteristics of bidisperse particles, which is subsequently validated and calibrated using dry separation experiments conducted on fine coal. The error is controlled within 10% while achieving a possible deviation E as low as 0.095 g/cm3.

Use of chia (Salvia hispanica L.) seed mucilage powder as a stabilizer in the preparation of salep beverage.

Salep, a traditional Turkish beverage, derives its name from its primary component: salep powder (SP), which is sourced from the tubers of certain orchid species. This study investigated various physicochemical attributes (including dry matter, protein content, pH, titration acidity, water activity, color, serum separation, and zeta potential), as well as rheological and sensory characteristics of salep beverages. These drinks were prepared by substituting SP with chia (Salvia hispanica L.) seed mucilage powder (MP) with different ratios (10%, 20%, 30%, and 40%). The substitution of SP with MP did not influence the dry matter and protein contents or the pH and acidity values of the drinks significantly (p > .05). The inclusion of MP in the formulation of salep drinks resulted in a decrease in lightness (L*) and a* color values while increasing the b* color values. However, consumer perception, as indicated by color difference values (∆E*), showed no distinguishable difference between drinks containing MP and control drinks. Furthermore, higher ratios of MP led to increased apparent viscosity values in the drinks and effectively prevented or significantly reduced serum separation observed in control drinks (p < .05). Remarkably, sensory evaluations revealed that substituting up to 30% of SP with MP did not negatively impact the overall sensory properties of the drinks (p > .05), suggesting that MP could be recommended as a feasible alternative. This substitution has the potential to contribute to the conservation of orchid plants, the primary source of salep, while also offering cost-saving benefits in the production of salep drinks.

Zero-valent iron (ZVI) facilitated in-situ selenium (Se) immobilization and its recovery by magnetic separation: Mechanisms and implications for microbial ecology

Selenium (Se(VI)) is environmentally toxic. One of the most popular reducing agents for Se(VI) remediation is zero-valent iron (ZVI). However, most ZVI studies were carried out in water matrices, and the recovery of reduced Se has not been investigated. A water-sediment system constructed using natural sediment was employed here to study in-situ Se remediation and recovery. A combined effect of ZVI and unacclimated microorganisms from natural sediment was found in Se(VI) removal in the water phase with a removal efficiency of 92.7 ± 1.1% within 7 d when 10 mg L−1 Se(VI) was present. Soluble Se(VI) was removed from the water and precipitated to the sediment phase (74.8 ± 0.1%), which was enhanced by the addition of ZVI (83.3 ± 0.3%). The recovery proportion of the immobilized Se was 34.2 ± 0.1% and 92.5 ± 0.2% through wet and dry magnetic separation with 1 g L−1 ZVI added, respectively. The 16 s rRNA sequencing revealed the variations in the microbial communities in response to ZVI and Se, which the magnetic separation could potentially mitigate in the long term. This study provides a novel technique to achieve in-situ Se remediation and recovery by combining ZVI reduction and magnetic separation.

Effect of blunging process on purification of halloysite ore from ferrous impurities by dry magnetic separation

The objective of this research is to study the effects of feed particle size, splitter angle, and washing process on Fe&lt;sub&gt;2&lt;/sub&gt;O&lt;sub&gt;3&lt;/sub&gt; removal efficiency in the separation of ferrous impurities from halloysite ore by dry magnetic separation in order to increase the purity of halloysite sample after crushing and blunging processes separately. Firstly, after crushing ore in a jaw crusher and sizing to -2+1 mm, -1+0.5 mm, and -0.5+0.212 mm fractions, the sized materials were fed to REMS-type dry magnetic separator at a constant belt speed of 300 rpm with the splitter angles of 0, 15, 30º separately. Maximum Fe&lt;sub&gt;2&lt;/sub&gt;O&lt;sub&gt;3&lt;/sub&gt; removal efficiency (FRE) (97.1%) was obtained in the nonmagnetic product at -0.5+0.212 mm size fraction and 0º splitter angle. The minimum Fe&lt;sub&gt;2&lt;/sub&gt;O&lt;sub&gt;3&lt;/sub&gt; content (1.3%) was reached in the nonmagnetic product obtained in the experiment with the feed size of -2+1 mm and a splitter angle of 0º. Secondly, dry magnetic separation was applied to the washed -2+0.212 mm size fraction after drying at room temperature to evaluate the coarse particle-sized halloysite ore that was gained by mechanical dispersion in the aqueous medium towards sodium hexametaphosphate (SHMP), while a significant part of the clay minerals went into fine size after the dispersion process. In the experiment performed with a 0º splitter angle after washing, it was determined that halloysite concentrate of 0.4% Fe&lt;sub&gt;2&lt;/sub&gt;O&lt;sub&gt;3&lt;/sub&gt; content could be obtained with 98.8% Fe&lt;sub&gt;2&lt;/sub&gt;O&lt;sub&gt;3&lt;/sub&gt; removal efficiency. As a result of dry magnetic separation experiments, it was seen that Fe&lt;sub&gt;2&lt;/sub&gt;O&lt;sub&gt;3&lt;/sub&gt; removal efficiency decreased as the splitter angle increased, while Fe&lt;sub&gt;2&lt;/sub&gt;O&lt;sub&gt;3&lt;/sub&gt; content in magnetic and nonmagnetic products increased. It was determined that washing and cleaning of fine-sized minerals plastered on particle surfaces after mechanical dispersion and particle release of minerals with different magnetic properties increased the dry magnetic separation efficiency, and nonmagnetic products with very low Fe&lt;sub&gt;2&lt;/sub&gt;O&lt;sub&gt;3&lt;/sub&gt; (0.4%) and high Al&lt;sub&gt;2&lt;/sub&gt;O&lt;sub&gt;3&lt;/sub&gt; (31.9%) content was obtained. The blunging process in the presence of dispersant caused the dispersion of clay minerals and allowed to liberating of the ferrous minerals from the halloysite ore, hence the increase in the FRE for the magnetic separation.