• Resources Recycling
• /
• v.29 no.3
• /
• pp.11-23
• /
• 2020

This study aims to investigate breakage and liberation characteristics of iron ore from Shinyemi mine, Jeongseon by ball mill. Parameters of breakage functions for three grade samples of iron ore were obtained using single-sized-feed breakage test and back-calculation based on nonlinear programming. The results showed that with the increase in the grade of iron ore, the breakage rate factor decrease whereas the particle size sensitivity decreases. This results from retardation of microcrack-propagation by magnetite grain in the ore. Breakage distribution analysis showed that the breakage mechanism appear to be impact fracture dominant with the increase of grade owing to the stress distribution effect by magnetite grain. Degree of liberation (DOL) increased with the increase in grade and decrease in particle size, respectively. Using the breakage function and size-DOL relationship, a model that can predict time-dependent-DOL is established. When scale-up factors from operating condition are available, the model is expected to be capable of predicting size and DOL with time in actual mining process.

• Resources Recycling
• /
• v.31 no.2
• /
• pp.12-19
• /
• 2022

The study was conducted to develop a vanadium recovery process using reduction pre-treatment in the Vanadium TitanoMagnetite (VTM) The sample for the research was provided by the Gwan-in Mine in Pocheon, Gyeonggi-do. The vanadium content of the sample is 0.54 V₂O₅% and vanadium is concentrated mainly in magnetite and ilmenite. Magnetic separation of the sample can increase vanadium content up to 1.10 V₂O₅%. To increase the vanadium content further, reduction pre-treatment was performed, which is a process of concentrating vanadium present in the iron by reducing iron in magnetite using carbon(C). Based on this reduction pre-treatment, the magnetic separation process was developed, which achieved a vanadium grade of 1.31V₂O₅% and 79.68% recovery. In addition, XRD analysis of the vanadium concentrate before and after reduction and the final vanadium concentrate was performed to confirm the behavior of vanadium by reduction pre-treatment.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.32 no.4
• /
• pp.387-396
• /
• 2012

A study was conducted to determine the dietary effects of Na-bentonite (NaB) and probiotics on meat characteristics and health of Hanwoo steers fed rice straw as a sole roughage source. A total of 24 growing Hanwoo steers (avg BW 232 kg) were assigned to two treatments which included a control diet (concentrate mix and rice straw) and a treatment diet (control diet + 0.5-1.0% NaB + 0.5-1.0% probiotics. The diets were fed for 22 months up to the time the animals were slaughtered. Dietary treatment increased (p<0.05) concentrations of trace minerals such as Zn, Cu, and Fe in the longissimus muscle compared to the control. The treatment diet did not affect cold carcass weight, yield traits such as backfat thickness, longissimus muscle area, yield index, yield grade and quality traits such as marbling score, meat color, fat color, texture, maturity and quality grade. Blood profiles of growing steers were within the normal ranges for healthy cattle. In conclusion, feeding a combination of clay mineral and probiotics to Hanwoo steers fed rice straw as a sole roughage source could have a desirable effect on improving trace mineral retention in longissimus muscle without any deleterious effects on carcass traits of steers.

• Journal of the Mineralogical Society of Korea
• /
• v.28 no.1
• /
• pp.1-7
• /
• 2015

Korea Institute of Geoscience and Mineral Resources (KIGAM) and Mineral Resources Authority of Mongolia (MRAM) performed test drilling in the right side of Deposit 2 in Ugii Nuur Fe-Mn occurrence area, Mongolia. It was decided to perform the drilling with 65 degree of drilling angle due to the technological limit of low angle drilling and designed to find ore bodies in cores between 50 m and 70 m. Ore bodies were found in lower depths than expected probably due to the folds in the subsurface in three drilling sites other than drilling position 3. Ore body in drilling position 3 was found in the similar depths with the expected depths. In drilling position 1, high Fe bearing ore body (more than 40%) was found between 47.45 and 50 m and between 56.35 and 57.1 m. The rest of ore body in drilling position 1 and ore bodies in other three sites have low Fe contents with about 10% of Fe. In drilling position 1, maximum and average Mn contents are about 10% and 1%, respectively, and in other three sites, average Mn contents are about 0.2%. Whereas Mn contents are low, Fe and Mn contents show very similar variations with varying depths, suggesting that they were moved and concentrated together in the ore genesis process. Proved resources estimated for the ore bodies confirmed by drilling are Fe 231,661 tonne with 11.82% of the average Fe grade. Possible resources supposing that ore bodies of DP-1 and DP-2 are connected and those of DP-3 and DP-4 are connected are Fe 4,415,296 tonne with 11.82% of the average Fe grade. The possibility of development of this area based on the estimated resources is low because the ore grade is low.

• Ocean Science Journal
• /
• v.41 no.3
• /
• pp.149-161
• /
• 2006

The aims of this study are 1) to construct a database using geostatistics and Geographic Information System (GIS), and 2) to derive the spatial relationships between manganese nodule abundance and other geological factors such as metal grade, slope, water depth, topography, and acoustic characteristics of the sub-bottom. Using GIS, it is possible to analyze a large amount of data efficiently, and to maximize the practical application, to increase specialization, and to enhance the accuracy of the analyses. The greater the copper and nickel grade, the higher the rating. The distribution pattern of nickel grade is similar to that of copper grade. The slopes are generally less than $3^{\circ}$ except for seamounts and cliff areas. The rating shows no correlation with slope. The rating is highest for slopes between 2.5 and $3.5^{\circ}$ in block N1 and between 4.0 and $4.5^{\circ}$ in block N3. The topography is classified into five groups: seamount, hill crest, hill slant, hill base or plain, and seafloor basin or valley. The rating proves lowest for seamount and hill crest. Our results show that the rating increases with the water depth in the study area. Nodule abundance dose not show any significant relationship with the thickness of the upper transparent layer in the study area.

• Resources Recycling
• /
• v.26 no.5
• /
• pp.39-47
• /
• 2017

In this study, the precipitation of rare earth-sodium sulfate with sodium sulfate was conducted in order to separate rare earth from Fe in rare earth sulfate solution. Neodymium (Nd) was easily precipitated as Nd-sulfate salt with sodium sulfate, on the other hand, excessive sodium sulfate was needed for the precipitation of Dy-sulfate salt. Also neodymium not only promoted the precipitation of dysprosium sulfate salt but also increased recovery of dysprosium sulfate salt in sulfuric acid solution. At the condition of $60^{\circ}C$ precipitation temperature, 3 h reaction time, 7 equivalents sodium sulfate, the recovery of neodymium and dysprosium sulfate salt was 99.7% and 94.3% respectively from the sulfuric acid solution containing Nd of 23.39 mg/ml and Dy of 8.67 mg/ml. Lastly, from the results of separation of Dy to Nd by the method of sulfate double salt, the effect of salting out with NaCl is important to increase the grade of Dy, and 98.7% of Dy grade could be obtained in this study.

• Geophysics and Geophysical Exploration
• /
• v.19 no.4
• /
• pp.212-219
• /
• 2016

The development of more advanced geophysical exploration techniques is necessary because the orebodies as yet discovered are increasingly changing in characteristics from shallow/high-grade to deep/low-grade. In this work, laboratory measurement of physical properties of rock samples and a field survey and interpretation of spectral induced polarization (SIP) have been conducted in a skarn metallic deposit, Gagok mine. The purpose of this study is that the applicability of SIP in the exploration of skarn metallic deposits is verified by the comprehensive interpretation between SIP characteristics of rocks obtained from the laboratory measurements and inverted survey results from the field data. In order to understand the SIP characteristics of each lithology, the data of eighty nine rock samples utilized in the previous studies were revaluated. The field survey was carried out using frequency of 0.25 Hz along a survey line designed for intersecting lithological boundaries and evaluating mineralized zones. The mineralized rocks were more conductive (low-resistivity) and capacitive (high-chargeability or strong-phase) than other rocks. Thus, SIP can be one of the very useful tools for the mineral exploration of the skarn deposits.

• Journal of the Korean earth science society
• /
• v.35 no.6
• /
• pp.422-428
• /
• 2014

Korea Institute of Geoscience and Mineral Resources (KIGAM) and Mineral Resources Authority of Mongolia (MRAM) performed a joint survey on Ugii Nuur Fe-Mn mineralized area. Following the survey, we carried out magnetic survey and 3D magnetic susceptibility inversion. Based on the inversion results, basic feasibility study and 3D imaging of Fe-Mn mineralized area were performed using 3D geological modeling technique. Using the distribution of total magnetic field data, we were confirmed for the possibility of horizontal extension of ore bodies from surface outcrops. The 3D magnetic susceptibility model, which is highly related with Fe content, analyzed by inversion shows that the ore bodies of Deposit 1 and Deposit 2 are extended to the underground and ore bodies that are not exposed on the surface are largely distributed in the underground. If we perform the integration analysis using this magnetic susceptibility model and the ore grade data analyzed by drilling survey, it is possible to carry out the effective potential evaluation of Ugii Nuur Fe-Mn ore deposit.

• Journal of Ginseng Research
• /
• v.26 no.4
• /
• pp.196-201
• /
• 2002

This study was carried out to compare the contents of saponins and minerals component in Korean Red Ginseng (Heaven, Earth, Good grade), North Korean Red Ginseng (Heaven, Earth, Good grade), Japanese Red Ginseng (Oonju, Sinju 1, 2, 3 grade, respectively) and Chinese Red Ginseng (Seokju, Gilim, 1, 2, 3 grade, respectively). Crude saponin contents were different on according to the grade and cultivation area, and was 3.05-3.76% in Korean Red Ginseng, 2.09-3.21% in North Korean Red Ginseng, 2.82-3.71% in Chinese Seokju Red Ginseng, 2.72-3.62% in Chinese Gilim Red Ginseng, 2.11-2.44% in Japanese Oonju Red Ginseng, 2.18-2.87% in Japanese Sinju Red Ginseng, and the amount of ginsenoside-Rb1, -Re, -Rg$\_$1/ in Korean Red Ginseng were higher than those of North Korean, Chinese and Japanese Red Gingsen. The contents of mineral components were similar, but La, Na and Sn component in Korean Red Ginseng showed the higher amount than those of other Red Ginsengs.

• Korean Journal of Microbiology
• /
• v.11 no.4
• /
• pp.189-195
• /
• 1973

With the gradual expansion of copper demands, the utilization of enormous tonnages of waste copper mineral containig up to 0.5% copper becomes available. In order to investigate the possibilities on the application of bacterial leaching method to waste dumps or abandoned mines, the authors had carried out microbial leaching of copper minerals by F.ferrooxidans isolated from the Dalsung copper mine water. The results obtained were as follows : 1. The copper extraction rate from the Dalsung chalcopyrite has been a little accerelated by using flasks in place of percolators. 2. The percentage of copper extracted from the Dalsung chalcopyrite sample was 100% in 30 days in the presence of iron-oxidizing bacteria F.ferrooxidans while 9.27% in the absence of bacteria. 3. F.ferroxidans was capable of producing sufficient quantities of ferric sulfate and sulfuric acid from ferrous iron to bring about the dissolution of 100% of copper from the Dalsung chalcopyrite.