Scientific Mining Journal

ABSTRACT

Small-scale rock cutting test (core cutting test) is one of the most frequently used rock cutting testing arrangements. Thanks to the experimental outcomes obtained from these testing arrangements, roadheader and bucket-wheel excavator performance prediction and rippability classification might be performed. However, these rigs are stable arrangements, are hard to be reproduced and they can be found in a very limited number of research centers. In the present study, application of small-scale rock cutting test with vertical rock cutting rig (VRCR), which is designed as a mobile rig and as an attachment to hydraulic bending test machines, was exclusively demonstrated. VRCR was basically introduced and results from previous studies were shown. It has been shown that small-scale rock cutting test may be applied easily and successfully with VRCR. Furthermore, a roadheader work site was visited and samples were collected. Cutting rate of the roadheader was predicted with the results of cutting tests in VRCR. As a result, cutting rate of the roadheader was estimated successfully. In the light of the obtained experiences and experimental results, it was shown that a rock cutting test may be performed as a routine rock mechanics test in VRCR.

ABSTRACT

In this study, pre-concentration possibilities of Murgul copper ore was investigated by using a laboratory scale teetered bed separator (TBS). Also effect of operational parameters on different minerals in the ore was evaluated. Results indicated that silica removal achieved in high mass and recovery before flotation. Gold and sulfur recoveries of TBS underflow was similar. An increase in pressure set point increases gold and sulfur recovery of TBS underflow. But an increase in teeter water rate decreases gold and sulfur recovery of TBS underflow. TBS tests were presented significant results about behavior of different density minerals under hindered settling conditions. The TBS underflow product which has highest gold and sulfur recovery was subjected to shaking table test as a pre concentrate. According to test results 11.63% of the shaking table feed can be concentrated with 4.39 ppm gold grade and 64.42% recovery as a final concentrate. The concentrate has also a higher sulfur grade as 48.46%.

ABSTRACT 

In this study, strategies for enrichment of iron ore samples of Demir Export A.Åž. via conventional magnetic separation were evaluated. Fe% and SiO₂ % of the iron ore used in the study is measured as in between 53.20-53.78 and above 10.5, respectively. Also, Al₂O₃ content is 2.3% and total alkali content (K₂O + Na₂O) is over 0.6%. Fe content of the ore meet the basic market sales requirements. On the other hand, silica, alumina and alkali contents are close to or slightly above the value defined as rejection limit. Experimental studies have been carried out in order to overcome these problems, especially the impurity content. Considering the current production method, it has been determined that the developed method should be a dry separation method, and therefore dry magnetic separation tests were planned and carried out. In addition, heavy liquid tests have been applied to reveal the best quality products that can be produced from the ore. Experimental studies have shown that 68% (61.26% Fe) and 92% (55.39% Fe) of products can be obtained from size fractions of -30 + 10 mm and -10 mm, respectively.

ABSTRACT

In recent years, several studies have been conducted to reduce the defects that may occur during the production phase with a view to ensure that the products introduced to the market under developing technology and competitive conditions meet the desired quality requirements. Statistical quality control is vital for the process of enhancing, improving and controlling the production phase. In this study, Shewhart control charts (the control charts for variables) are obtained for the purpose of identifying any potential change in the thickness and brightness values for two different natural stone samples produced in the natural stone plant in Afyonkarahisar / Turkey. Statistical process control techniques, which play a key role in those quality studies, help businesses improve, enhance and control the production processes. Thanks to statistical process control techniques, the problems experienced during the production processes could be identified and the causes of those problems could be analysed to take action in order to prevent recurrence of the situation.

ABSTRACT

Today, nearly all commercial production of alumina is obtained from standard Bayer process using bauxite ores as a raw material. One of the most important criteria for metallurgical-grade bauxites that can be directly fed to the Bayer process is the total silica content of bauxite. Because, reactive silica which tends to dissolve during bauxite leaching causes excessive caustic soda consumption and alumina losses in the Bayer process. For this reason, the reactive silica content in bauxite plays a critical role in the viability and economics of the Bayer process. Removing reactive silica from bauxite prior to leaching (also known as pre-desilication) is a major focus of effort for most alumina production plants. In recent years, it has been known that beneficiation methods such as froth flotation have been tried to pre-desilication. In this study, the major problems caused by reactive silica in bauxite ore and several beneficiation methods used for pre-desilication have been reviewed from the current literature. Among these methods, it has been determined that froth flotation is more important in terms of silica removal performance and industrial practice, and so investigations on bauxite flotation have been discussed extensively.