In this research, the effect of microwave radiation on the surface chemistry and liberation degree of copper Sulfide minerals (Sarcheshmeh and Palangi ores) was investigated. In flotation studies on the effect of microwave radiation on the surface chemistry, after 90 seconds radiation, the concentrate grade and recovery of the Sarcheshmeh samples increased 7 and 2 percent; respectively but the concentrate grade and recovery of the Palangi samples decreased 4 and 8 percent, respectively. Also, in flotation studies on the effect of microwave radiation on the liberation degree, after 180 seconds radiation, the concentrate grade and recovery of the Sarcheshmeh samples increased 4 and 6 percent respectively but for the Palangi samples, a same increase in the grade and recovery was obtained in 600 seconds of microwave radiation. Furthermore, flotation rate constant of the Sarcheshmeh and Palangi samples increased 0. 2 and 0. 1 per minute respectively, after 120 seconds microwave radiation.

Generally, mineral processing plants generate a large quantity of waste in the form of fine particles. The flotation speed of mineral microbubbles by coarse bubbles is dramatically higher than that of individual particles. The advantage of microbubbles is due to the increase of binding efficiency of conventional bubbles with fine particles coated with microbubbles. Here, the focus is on reducing chemicals consumption and improving recovery. After preparing a representative sample, XRF, XRD, and mineralogical analyses were performed. Then 50 experiments were selected by experimental design using the response surface method (RSM), and in the form of central Composite design (CCD) by (design expert) DX 13 software. The interactions of collector consumption, frother agent, pH, particle size, and solid percentage were investigated, and 25 experiments using typical flotation and without nano-microbubbles and others with nano-microbubbles were conducted. The laboratory standard limit of the collector used in the pilot plant of the Sarcheshmeh copper copper complex is 40 g/t (25 g/t of C7240 plus 15 g/t of Z11). Here, by consuming 20 g/t of collector in the absence of nanomicrobubbles, a recovery of 79.96% and in the presence of nanomicrobubbles, a recovery of 80.07% was obtained, that is a 50% reduction in collector consumption and a 0.11% increase in recovery was observed. Also the laboratory standard limit of frother used in the pilot plant of Sarcheshemeh copper Complex is 30 g/t (15 g/t of MIBC plus 15 g/t of A65). Here, by using 10 g/t of frother in the absence of nanomicrobubbles, a recovery of 78.12%, and in the presence of nanomicrobubbles, a recovery of 82.05% was obtained. In other words, a decrease of 66.6% in the consumption of frother and an increase of 1.93% in recovery was observed.

flotation is the most important method for processing Sulfide copper ores. Due to the high cost and environmental hazards caused by the chemical reagents used in this process (collectors, frothers, pH regulators, depressants, etc.), the possibility of replacing all these reagents or at least some of them are of special importance through environmentally friendly methods such as bio-flotation using halophilic bacteria. These bacteria have the ability of growth and proliferation in salty media and relatively neutral pHs such as sea salty water. In this research work, the four types of halophilic bacteria Halobacillus sp., Alkalibacillus almallahensis, Marinobacter sp., and Alkalibacillus sp. are studied to replace frothers (MIBC and F7240), depressant (sodium metabisulfite), and pH regulator (lime) in Sulfide copper flotation using a Denver laboratory flotation cell. The results obtained indicate that each of the four types of bacteria mentioned above along with collectors (gasoil, Z11, and C7240) as the only chemical reagents (bio-flotation + collector) can depress pyrite better than the bacteria-free mode (flotation + all chemical reagents). Iron recovery in tailings in the standard flotation test is 46.8%, which is, respectively, increased to 91.9%, 74.5%, 70.3%, and 76.9% using the halophilic bacteria of Halobacillus sp., Alkalibacillus almallahensis, Marinobacter sp., and Alkalibacillus sp. On the other hand, the recovery of chalcopyrite using the bio-flotation method is lower than its recovery using the flotation method. copper recovery in the concentrate in the standard flotation test is 89.1%, which is reached to 58.8%, 71.4%, 62.5%, and 69.4%, respectively, using the above bacteria in the bio-flotation method.

A Sulfide copper ore was crushed to 100% passing 3. 36mm followed by grinding the crushed product through bed breakage process in a piston-die cell or ball mill into to 100% passing 250μ m. Revealed by the results of particle size analysis made on the ground products, the bed breakage method provides a finer product compared to the ball mill approach. The liberation analysis of the products in eight size-fractions showed that the chalcopyrite in the ball mill product was more liberated compared to the bed breakage product. The overall percentage of chalcopyrite liberation in the ball mill product was higher than the bed breakage product by 1. 82%. The shape properties of particles in the breakage products were examined by analysis of scanning electron (SEM) images. Accordingly, it was found that the circularity and roundness of particles broken by the bed breakage method are higher than the particles broken by the ball mill method, while the ball-milled particles are more elongated. The results of micro-flotation tests indicated the efficiency rate of Cu recovery and separation in the ball mill product were respectively 11% and 15% higher than the bed breakage product. This better metallurgical performance can be attributed to the fact that the bed breakage product was finer, the chalcopyrite was more liberated in the ball milling product, and particles in the ball milling product had less circularity and roundness. Contrary to many previous studies, the results of this study indicated that the bed breakage method did not increase the mineral liberation and improved the performance of the flotation process.

copper oxide minerals such as malachite do not respond well to the traditional copper Sulfide collectors, and require alternative flotation schemes. In many copper ore mines, significant copper oxide minerals, especially malachite, are associated with Sulfide minerals. Considering that xanthates are most widely used in the flotation of Sulfide minerals as well as copper Sulfide minerals and, hydroxamate has shown a good selectivity for copper oxide minerals. Use of the synergistic effect of xanthate and hydroxamate can be an effective way to increase the flotation efficiency of copper oxide minerals along with Sulfide minerals. In this work, we investigate the individual interactions of potassium amyl xanthate (PAX) and potassium alkyl hydroxamate (HXM) with the natural malachite and explore their synergistic effects on the malachite flotation. The results of solubility of malachite in collector solutions, changes in the malachite surface potential, adsorption kinetics, adsorption densities, dynamic contact angles, FT-IR analyses, and small-scale flotations, are discussed. The results obtained demonstrate that PAX and HXM are chemically co-adsorbed on the malachite surface, and the amount of PAX adsorbed on the malachite surface is considerably increased in the mixed PAX/HXM systems because of the co-adsorption mechanism. The flotation results confirm that the mixed PAX/HXM exhibit a superior flotation performance of malachite compared to the individual system of PAX or HXM. Based on these results, the mixed PAX/HXM exhibit a remarkable synergism effect on malachite surface hydrophobicity.

Nowadays, seawater usage in mineral processing has become a fairly topical issue. Due to rapid population growth and industrial development, the amount of fresh water is decreasing rapidly, so that fresh water is a critical component, especially in many industrialized arid countries, such as Iran. One of the main methods of mineral processing is flotation process that occurs in aquatic environments and consumes large volumes of water. The purpose of this paper was to investigate the use of sea water in the Cu-Mo ores froth flotation. In the experimental work, seawater was utilized as process water in the laboratory rougher flotation tests and compare the results with fresh water. The ore sample was porphyry Cu-Mo ore, which was delivered from Sarcheshmeh copper complex. Results show that recovery of copper maintained almost the same level in both mediums. However, lime consumption was observed to be increased significantly under flotation conditions in seawater. In addition, the floatability of molybdenum was affected negatively above the pH 9.5-10. Recovery reduction of molybdenum was suggested to occur due to the magnesium hydroxide complexes and magnesium hydroxide precipitates, which began to form in seawater in higher pH levels. The experimental work showed that the conventional flotation of Cu-Mo ore conducted in seawater has serious conflicts, when pyrite is depressed with lime.

Optimization of the processes is one of the most important tasks today, for highly competitive industries. High cost of research and development activities has necessitated development of the experimental methods by which the factors affecting a process could be determined by performing a minimum number of experiments. These types of experimental designs have been used since 1980.Among different methods of experimental designs, the Taguchi method -because of its comprehensive nature and its ability to enable designs which are resistant to uncontrollable parameters has found wide spread applications.The Sarcheshmeh copper ore, which mainly consists of Chalcopyrite, was studied by Taguchi method. The effect of seven factors namely collectors, Z11 and R407, frothers, pine oil and A65, particle size, pH and residence time were investigated. The results showed that an increase of minimum of 5% in copper recovery could be obtained using the Taguchi type of experimental design.

The cleaner circuit at Miduk copper concentrator consists of 3 parallel flotation columns (4m in diameter and 12m in height). The cleaner concentrate is re-cleaned by 3 parallel flotation columns (3. 2m in diameter and 12m in height), when the desired concentrate grade is not reached by the cleaner columns alone. This research work deals with simulation of the cleaner column flotation circuit at Miduk copper concentrator using USIM PAC simulator with the aim of improving the process metallurgical performance. For that purpose, the parameters of the models including flotation rate constants (kf, ks), residence time distribution (RTD), gas hold-up in collection zone (ε g), mean bubble size (db), collection (Rc) and froth (Rf) zone recoveries along with some operating and geometrical variables were determined. The flotation rate constants were calculated by fitting the experimental data to the fast and slow floating components model. The residence time distribution of the flotation columns was measured by the tracer injection technique (using saturated NaCl solution as tracer). The gas hold-up and mean bubble size in the collection zone of the cleaner columns were estimated from the pressure difference and the drift flux techniques, respectively. The froth recovery was quantified by measuring the concentrate mass flow rate at different froth depths and extrapolation to the zero froth depth. The cleaner circuit was sampled five times, of which three times were used for calibration and two times for validation of the models. The mass flow rate, copper content and size distribution of the cleaner columns concentrate and tailings were accurately predicted using the simulation models. Increasing the number of operating cleaner columns improved the copper recovery (from 45. 67% to 54. 64%) at the expense of a reduction in the final concentrate (from 26. 17% to 24. 22%). The number of recleaner stages in all cases improved the the final concentrate (from 26. 17% to 36. 99% in the circuit with 2 cleaners and from 24. 22% to 36. 13% in the circuit with 3 cleaners). Increasing the feed slurry solids concentration reduced the size-by-size fractional copper recovery of the cleaner columns. Increasing the feed slurry solids concentration reduced the cleaner columns copper recovery in all size fractions. The best configuration of the cleaner and recleaner flotation columns was proposed.