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Egyptian feldspar ores are usually of low grade and need beneficiation to improve their grade for industrial applications. Therefore, feldspar should be ground to a reasonable liberation degree prior to beneficiation processes. Mineralogical studies showed that a good degree of liberation is below 0.25 mm. This work aims to optimize the grinding parameters for an Egyptian feldspar ore that ensures maximum production of size −250 + 45 µm and minimum % − 45 µm. Grinding was performed using a laboratory ball mill. The results displayed that the grinding performance was increased with decreasing the solid content with U between 0.5 and 1. A high milling rate was achieved at ball filling 20–30%. The ideal ball-filling ratio was determined to be 25%, with less production of fines. Hence, it was decided to crush the feed to less than 2 mm before grinding with 36.6 mm balls to reduce fines. [ABSTRACT FROM AUTHOR]

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The demand for feldspar as a raw material for various industrial applications continuously increases. Feldspar is a primary raw material in manufacturing ceramics, glass, fillers, welding electrodes, and enamel. Feldspar is often associated with iron oxide, which decreases its economic value and hinders its industrial application. The present work aimed at reducing iron oxide content in Egyptian feldspar ore from the Wadi Zerabi locality. Ball milling was used for preparing feldspar feed of size -250+45µm. Carpco dry high-intensity magnetic separation followed by acid leaching processes were carried out in order to decrease the iron contamination and increase the feldspar content. A Box-Behnken statistical design was used to optimize the magnetic separation results. From a feldspar feed containing 1.40% Fe2O3, a non-magnetic concentrate of 0.25% Fe2O3 was obtained. The Fe2O3 removal reached up to 82% with a high yield as the % weight of non-magnetic feldspar reached up to 97.5%. The leaching process further reduced the iron oxide content down to 0.19 %. Also, the feldspar whiteness was improved from 65.17% in the original ore to 85.60% in the leached product. [ABSTRACT FROM AUTHOR]

Coal plays a major role in the economic development of many countries, especially in metallurgical industries and conventional power generation plants. The removal of sulfur from coal has recently become even more critically important. Existence of sulfur compounds in coal limits its industrial applications due to environmental as well as technical problems. Thus, high sulfur coal is usually upgraded by desulfurization through physical, chemical, and biotechnological processes. In this study, lowering of pyritic sulfur took place after thermal treatment at 500–700°C (pyrolysis) using a wet high-intensity magnetic separation process. The samples were subjected to size reduction to −25 µm and characterized with X-ray diffraction (XRD), proximate and ultimate analysis, and differential thermal analysis (DTA). Then, the experiments were performed based on central composite rotatable design (CCRD) and response surface methodology (RSM) after thermal treatment of coal containing 3.30% total sulfur. Statistical analysis was performed to examine the significance of the effect of different operating parameters. A maximum sulfur rejection of 90.10% with the lowest sulfur content of 0.59 was obtained at 8.38% solid concentration, 4.59 g/min feed rate, and 7810 gauss magnetic field intensity. The confirmation tests at the optimum conditions produced 0.54–0.56% total sulfur with 90.25–92.33% sulfur rejection. [ABSTRACT FROM AUTHOR]

In this study, an Egyptian siliceous/calcareous sedimentary phosphorite was subjected to beneficiation by unsophisticated economic means. The mineralogical and chemical examination showed that the ore sample is a typical example for the East Mediterranean phosphorites with 21.80% P2O5, 10.93% acid insoluble and 16.61% loss on ignition. The primary crushed sample was classified into three size fractions without any milling and they were separately subjected to an integrated attrition scrubbing study. Screening and classification on the 2.30 mm and 0.071 mm sieves were sequentially introduced with the attrition process. The effect of solid%, attrition speed and time were studied and optimized for each size fraction. Results showed that three products were produced and could be categorized according to their P2O5 content into the coarse tailing (+2.30 mm), the attrition concentrate (−2.30 + 0.071 mm) and the phosphate fines (−0.071 mm). The P2O5 contents of these products reached 12.24%, 28.72% and 18.77%, with P2O5 distribution reached 6.74%, 51.75% and 41.51%, respectively. A global P2O5 of 28.72% was obtained with a recovery of about 52%. A tentative flow-sheet for the whole process was postulated. [ABSTRACT FROM AUTHOR]

The present study aimed at studying the recycling of shredded currency waste of The Egyptian Central Bank, ECB, in the form of good-quality products. The techniques used include soaking with chemicals, screening to separate the detached ink particles from the soaking step, pulping at high temperature, screening to separate large nylon pieces and small ink particles, flotation to separate large ink particles and small pieces of nylon and bleaching as the final step to increase the whiteness of the product. [ABSTRACT FROM AUTHOR]

Minerals in ore were evaluated by XRD & XRF. A number of parameters including solid/liquid ratio S/L, bowl rotation frequency, back water flow rate were studied on the process performance. At the optimum conditions a concentrate contain 62.16% Fe, and 7.62% SiO2 from the original contains 49.33% Fe, 21.18% silica was obtained and be used in the reduction process. This concentrate used in studying the different reduction processes after mineralogical study. [ABSTRACT FROM AUTHOR]

Cationic flotation is one of the most widely accepted technologies for upgrading siliceous iron ore using polysaccharides (mainly starches) as depressing agents for iron bearing minerals while floating silica with amines. In this paper, a group of starches are investigated as depressants for hematite. These starches are: wheat, corn, rice, potato, and dextrin. The role of starch type of the selectivity of separation process has been studied through zeta potential, adsorption measurements as well as flotation tests. The effects of type of starch and pH of the medium have been studied. The results indicated that the selectivity of the separation process is strongly affected by the type of starch used where better results are obtained with corn starch or wheat starch in comparison to the other types. FTIR measurements indicated that the interaction between starches and iron oxide surface are intermolecular interaction. [ABSTRACT FROM AUTHOR]