و .
p-value
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(ب- ۹)
Abstract :
Manganese is used as an important and useful metals in metallurgical and non ferrous alloy industries .Because of the importance of this ore , recovery of manganese from low grade ores is economically feasible.In this study, feasibility of concentrating of Jiroft’s Mohammadabad manganese ore has been studied. Based on chemical analysis , the grade of manganese , Fe2O3 and Sio2 are determined 21, 19.66 and 32.07 respectively. Mineralogy Studies of samples showed the existence of fine crystals of manganese bearing ores and also locking with gangue minerals of the sample.In XRF tests, the manganese ores are not distinguished because they were amorphous and their crystality were low. Weight tests were done by using jig separators for grading size -3000 Micron to 1000 micron and the results showed 23.61 % of manganese grade. For particle sizes of -1000 -+300 , -300 and -100 Micron, recovery test has been done by using shaking desk which resulted the best concentration grade of 31.14 % and best recovery grade of 30.34%.In order to increase recovery of the manganese, dry and wet magnetic separators has been used for concentrating of intermediate product of shaking desk for the particles in the range of -300 Micron.In the next phase , floatation tests has been done for -100 Micron particles which resulted manganese with grade of 27.59 % at the best practice.As the results of the study showed, common and ordinary physical and floatation methods are not useful for concentrating the manganese ore of Mohammadabad as the ore has been recognized as hard ore manganese. Therefore the chemical methods such as reductive leaching is more appropriate method for concentrating this ore . The last phase of this study , different phase of reductive leaching has been studied and the results have been analyzed. Reductive leaching showed the best recovery of manganese in comparison to the other methods.Oxalic acid has been adopted as the effective reductive in this method and also it has been distinguished as leaching control parameter.By using Test design software, CDD method with 30 leaching test has been adopted. In this test % 14.4 solid material , 60 g/l Sulphuric acid , 49.93 g/l Oxalic acid in 70 centigrade temperature , recovery of manganese , FE and Sio2 were %88.4 , % 6.57 and %0.66 respectively .
Keywords: Manganese ores concentrating, Mohammadabad – Jiroft Mine , Reductive Leaching , CCD Method.
The University of Kashan
Faculty of
Department of mining engineering
Thesis
Submitted in Partial Fulfillment of theRequirements for the Degree of Master of Science (M.Sc.) in Mining Engineering
Title:
Manganese ore processing feasibility of Jiroft
Supervisor:
Ali Akbar Abdolahzadeh
By:
Newsha Omid Shafaat
March 2015
Manganese ↑
Transition Metals ↑
Endogenetic ↑
Manganese Ore ↑
Manganiferous Ore ↑
Ferrugenous Manganese Ore ↑
Manganiferous Iron Ore ↑
Spotty manganese ↑
USGS ↑
Concentration Criterion ↑
EDTA ↑
cane molasses ↑
Waste tea ↑
EAFD ↑
Molasses ↑
EM ↑
EMD ↑
CMD ↑
XRD ↑
XRF ↑
Shirinking Core Model (SCM) ↑
Concentration Ratio ↑
Enrichment Ratio ↑
One – way analysis of variance ↑
Pooled variance estimates ↑
Variance of group means ↑
Unbiased estimate ↑