فهرست مطالب خداکرم غریبی

Froth stability is of particular importance and  has a significant impact on the flotation process. Froth stability can be defined based on the formation of froth (maximum froth height or froth retention time) or the froth decay (froth half-life). Froth stability is influenced by various factors such as the superficial air velocity (Jg), the collector dosage (CC), frother dosage (FC) and the sample particle size (d50). In this work the effects of these factors were examined. The results showed that increasing the Jg, the CC and the FC will increae the froth stability. For example, by increasing the FC from 60 to 140 g/liter, the froth retention time (FRT) and the half-life froth (t1/2) increased by 92% and 71%, respectively. Sample particle size behaved differently in froth formation and decay, so that by reducing the d50, the froth retention time increased but the froth half-life decreased.

The froth phase plays an important role in the recovery of minerals and the grade of concentrates in flotation machines. In the present work, the concept of bubble load was used to calculate the froth recovery. The results showed that the froth depth, aeration, and frother concentration are the most important operational parameters affecting the froth recovery in the flotation cell of hematite circuit of Gol Gohar Iron Ore. The results showed that increasing the aeration and frother concentration, and reducing the froth depth were caused to increase the froth recovery; For example, when aeration, frother and froth depth are respectively 146 m3/h, 150 ml/min and 5 cm, the froth recovery is more than 84%. Also, increasing the depth froth, aeration, and frother concentration were caused to increase the amount of sulfide minerals in the froth phase. Moreover increasing the aeration and frother concentration, and reducing the froth depth were caused to increase the amount of sulfide minerals in the concentrate.

More than 80 percent of the water used in the flotation process Sarcheshmeh Copper Mine is provided from recycled water of tailing dam. Due to the water shortage problem in the current condition, evaporation is considered the most important factor of losses from this important resource. In this study, were introduced two chemicals including hexadecanol and octadecanol. The two chemicals have a significant impact in reducing evaporation from open water reservoirs of mine that these reservoirs is provided much of the water in the flotation circuit. In the following, the combination of these two substances were added to five different water samples and were examined its impact on the recovery of the three mineral, copper, pyrite and molybdenum and then, the significance of the observed differences flotation tests on water samples were analyzed using Duncan's multiple range test. The results showed, fatty alchohol not only have not been a negative impact on the recovery of three mineral copper, pyrite and molybdenum, but also have increased 0.1% recovery of copper and 3.5% molybdenum recovery. Moreover, have increased pyrite arrested an estimated 30%.

Mine and deposit are the one of the major part of economic fundamentals in any country. Sistan and Bloochestan located in the south-east of Iran has the noticeable and mineable deposited. Chromite's reserve is the considerable potential for development in this province.
By attention to the reserve of Chromite in Sistan and Beloochestan province Manufacturing and running a mineral processing plant for Chromite is necessary. This research is carried out for Site selection of Mineral processing plant for Chromite in Sistan and Beloochestan province.
The research method in this article is practical by looking to aims and surveying based on the data collection methods. The research were carried out by using of Groups AHP and SAW methods and BORDA combined method. By helping of fifteen members of university and industrial expert in mining technology, also by data collection of government offices, For selected the best selection eight criteria were investigated after nomination the suitable selection.
Zahedan was selected by Groups AHP and SAW methods. It is using of the multiplied Borda method for the better judgment and multiplied these methods. Finally Zahedan was recognized as the best place for manufacturing and running a mineral processing plant for Chromite.

In this research the application of external potential to reduce the amount consumption of depressant in a copper- molybdenite flotation circuit was studied. Control of the pulp in electrochemical flotation can be carried out by changing the electrochemical parameters like Eh، pH and oxidation and reduction reactions. One of the electrochemical flotation methods is application of external potential in which the flotability of minerals is considered. In this paper the feasibility of chalcopyrite removal from a copper-molybdenite concentrate is presentedinvestigated. The rResults showed that usage ofing external potential can be consideredbe considered as an alternative method for reducing the other depressants usageconsumption.

Solvent extraction was applied for the purification of a solution obtained from acid leaching of Mehdiabad oxidized zinc ore. The zinc PLS contained manganese and iron ions. D2EHPA was selected as a suitable organic extractant. At the begining, the effect of pH of aqueous phase and D2EHPA concentration in krosene were studied. Then the necessary numbers of stages were obtained by Mccabe Thiele diagram. D2EHPA at low pH (2.5) and 30% concentration was able to extract 87% of zinc from aqueous phase by 3 stages in the presence of Mn ions. At the end of process stripping experiment was performed by fresh sulfuric acid solution. At this stage, about 95% Zn ion was transferred from organic phase to aqueous phase.

This paper presents the results of first stage investigation of phosphate recovery from fine particles in Esfordi phosphate beneficiation plant. The aim of this investigation was the optimization of flotation process for increasing the phosphate recovery and decreasing the Iron content of concentrate. Experimental design, Taguchi method, was applied to investigate the effects of 8 factors namely, collectors ratio, collectors dosage, pH, starch dosage, pulp density, conditioning time for starch, conditioning time for collectors and frothing time. 4 responses, namely phosphate recovery, phosphate grade, iron recovery and iron grade were measured and evaluated to determine the optimum conditioning of each response. The orthogonal array L27(313) was used for the evaluation of the above factors on the responses of design. Statistical analysis of results showed that starch dosage, pulp density an frothing time had more impact on the phosphate recovery. The optimum condition for each response was introduced and the best condition for phosphate grade in concentrate was compared with the ruling condition in beneficiation plant. The comparison of results showed acceptable improvement in concentrate quality.