Quadratic Mathematical Modeling of Sustainable Dry Beneficiation of Kaolin

Clay minerals are one of the most utilized minerals among non-metals. These are hydrous aluminum silicates with a layer (sheet-like) structure. Kaolin is a hydrous aluminosilicate mineral with a thin platelet structure. Kaolin is extensively used in paper, paint, and many other industries. Wet processing of kaolin will not be sustainable over the long term because global freshwater resources are becoming scarce. Hence, a process is necessary that does not consume water during the beneficiation of kaolin. This study developed a dry beneficiation process for low-grade kaolin of 59.6%, with 12% quartz and about 6% titaniferous impurities from Nagar Parkar, Sindh province, Pakistan. To develop a size difference between kaolinite and impurities, steel balls clad with rubber were used as the grinding media in a selective grinding unit. Screens of 60 and 400 mesh were employed to classify the feed of air classifier. Oversize +60 mesh was reground, 400 to 60 mesh fractions were sent to an air classifier, and −400 mesh was considered to be a product with the grade and recovery of 90.6% and 20.5%, respectively. Air classifier experiments were designed using central composite design. An experiment using a fan speed of 1200 rpm and a shutter opening of 4.0 showed optimum results, with maximum kaolinite grade and recovery of 91.5% and 35.9%, respectively. The statistical models developed for grade and recovery predicted the optimum results at a fan speed of 1251 rpm and shutter opening of 3.3 with the maximum kaolinite grade recovery of 91.1% and 24.7%, respectively. The differences between experimental and predicted grade and recovery were 0.1% and 2.4%, respectively. The characterization results showed the total upgrade of kaolin from 59.6% to 91.2%, with 27.1% recovery. The designed methodology has the potential to improve the yield of the product by focusing on its recovery. Furthermore, the designed process can be improved by using different sized balls in the selective grinding unit. This beneficiation process can utilize more than one air classifier in series to achieve the targeted results.

Economic and Socio-Environmental Benefits of Dry Beneficiation of Magnetite Ores

In our previous studies, we demonstrated the performance of novel superfine crusher and pneumatic planar magnetic separator as energy-efficient technologies for dry processing of magnetite ores. The present study investigates the economic and socio-environmental benefits of applying these technologies in conceptual dry magnetite ore processing flowsheet. The outcome of the study is compared with that of a conceptual wet processing flowsheet for the same ore. The cost estimations used are based on the Brook Hunt C1 methodology whilst revenue estimations are based on the Platts Iron Ore Index specification. The demonstrated economic and socio-environmental benefits show that dry processing flowsheet offers significant energy and cost savings and improved revenue generation compared with the wet process flowsheet. These findings are vital to the magnetite industry, particularly in water- and energy-scarce regions as a benchmark for future studies aimed at deepening and expanding the knowledge base of dry beneficiation of magnetite ores.

A Novel Pneumatic Planar Magnetic Separator for Magnetite Beneficiation: A Focus on Flowsheet Configuration

In our previous studies, we investigated the performance of a novel pneumatic planar magnetic separator (PMS) for the dry beneficiation of a selected magnetite ore. In the present study, we have extended the studies on the PMS with the focus on investigating how various PMS processing flowsheet configurations influence its performance. The outcomes were subsequently compared with those of a Davis tube recovery (DTR) tester. The study demonstrated that the use of PMS in the dry beneficiation of magnetite ores is feasible, and operating the PMS in different flowsheet configurations positively influences the magnetite concentrate grade and purity. Finally, the study showed that the PMS performance compares well with that of DTR and can potentially replace DTR in operations that are carried out in arid regions.

DRY MAGNETIC SEPARATION OF MAGNETITE ORES

The relevance of the paper is that dry magnetic separation (DMS) is the main beneficiation method of magnetite ores. The lack of efficient industrial-grade machines and apparatus for separating fine-grained magnetite ores means that DMS is used mainly as a pre-concentration operation for fairly large classes. The aim of the research is to study the possibility of using a new magnetic separator model in the process of dry beneficiation of magnetite ore from the Bapy deposit. This paper presents theoretical and experimental studies of a new model of a magnetic separator. The mathematical modeling of the magnetic separation process of the device was carried out to evaluate the parameters in accordance with which a laboratory separator was subsequently manufactured. For the experimental study of the properties of this magnetic system, a laboratory magnetic separator was built. The possibility of using a new magnetic separator in the process of dry beneficiation of magnetite ore from the Bapy deposit was investigated. The industrial scheme being implemented consists in ore crushing and two stage dressing on dry drum magnetic separators. The study of beneficiation indicators of the magnetic separator was carried out using iron ore of the Bapy deposit, which is mono-mineral magnetite. For the study, mixtures of the minus 0.1 mm class were selected with the iron content α = 50% and α = 40%. As a result of the research, beneficiation indicators were obtained on a laboratory scale. Therefore, the improvement of the beneficiation scheme is reduced to the isolation of a small product and its subsequent beneficiation using a new model of magnetic separator. Thus, the presented magnetic separator is suitable for dry processing of crushed magnetite ore.