Mining Solutions

Mining Solutions

 

 

CUC-chem Delivering Innovations for The Global Mining Industry

 

A leading supplier of chemical reagents to the mining industry for over 17 years CUC-chem a member of creative united group enables customers to improve productivity and reduce operating costs while meeting complex economic, environmental and metallurgical challenges. As the demands of the industry are changing, CUC-chem is partnering with mining companies around the GCC to deliver reagent solutions for the recovery and production of copper, alumina, gold, nickel/cobalt, phosphate, iron, polymetallic ores and many other metals and minerals.

 

We provide onsite support, where our experienced team works right alongside you to resolve your challenges with robust solutions. As a recognized global leader, we can offer you peace of mind through our commitment to reliable product supply. CUC-chem is a premier supplier and a long-term partner for your business.

 

Our products have optimized mining operations worldwide in alumina processing, mineral processing and solvent extraction. Please contact a CUC-chem representative to discuss your operational challenges so they can offer a solution to address your specific requirements.

 

 

CUC-chem Mining products:

 

 

·       Flotation Collectors:

 

PICTURE

 

Collectors – CUC-chem ® AR series collectors:

 

A collector is a chemical that attaches to the mineral surface and produces a hydrophobic (water-fearing) surface. While certain minerals are naturally hydrophobic and do not require a collector, recovery is often improved when a collector is used. This water-repellent film facilitates the attachment of the mineral particle to the air bubble. Many different chemicals are used as collectors, such as:

 

o   oils

o   xanthates

o   dithiophosphates

o   petroleum sulfonates

o   fatty amines

 

 

·       Solvent Extractants:

 

PICTURE

 

We offer a broad range of solvent Extractants for purification & concentration of copper, nickel/cobalt, molybdenum, rare earths and various other metals.

 

Our oxime-based CUC-chem AR EXT range of copper Extractants have a proven track record in the industry and are used by the largest copper producing mines in the GCC countries. They include a wide range of modified aldoximes, modified aldoximes, ketoxime blends, as well as specialized nitration-resistant and oxidation-resistant Extractants. We can advise on the optimal reagent formulation to meet the specific conditions and challenges for a given operation.

 

Our phosphinic acid-based CUC-chem AR phos 100 range of Extractants are used in a wide range of metal applications such as:

 

1.     separation of cobalt from nickel

2.     separation of cobalt and nickel from manganese and magnesium

3.     the extraction of molybdenum

4.     recovery of rare earth elements

 

CUC-chem also offers a range of processing aids to promote organic phase quality, improve efficiency of clay treatment or optimize electro winning operations.

 

 

CUC- Solvent Extraction

 

Solvent extraction is a hydrometallurgical process. The process entails:

 

1.     Dissolution of the metal in an aqueous, typically acid, solution

2.     Transfer of the dissolved metal to an organic solution

3.     Transfer of the dissolved metals to a second aqueous solution

4.     Production of a product

 

The product is usually electroplated to produce the pure metal or precipitated from the solution to produce a metal salt. Copper, uranium, vanadium and other metals are produced by solvent extraction. The figure below is a simplified schematic of a typical copper solvent extraction process.

 

PICTURE

 

Oxide copper ore, low-grade copper sulfide overburden, and other copper-containing materials are stacked into a heap. Leach solution (pH approximately 2) is sprinkled or flooded on top of the heap and percolates through. The leach solution containing the dissolved metal eventually flows out of the heap into a collection pond. This material is referred to as pregnant leach solution. Oxide copper minerals are very soluble in the leach solution. Sulfide minerals are rendered soluble by certain bacteria that feed on the sulfide minerals and convert them to soluble sulfates and other soluble forms. This biological action tends to maintain the acidity of the leach solution. Typical operations will leach some areas of the heap, enlarge other sections, and let others rest.

 

The pregnant leach solution is pumped to the extraction mixer where it is intimately mixed with organic solution. The organic solution is a chelating agent diluted in a hydrocarbon solvent. The chelate reacts with the copper and removes it from the aqueous phase. The mixture flows to the settler where the organic phase and aqueous phase separate. The aqueous phase, now called raffinate, is pumped to the raffinateponds and eventually back to the heap to leach more copper.

 

The loaded organic phase goes to the strip circuit where it is mixed with a strong acid solution. The chelate releases the copper to this aqueous phase, called the strip solution. Again the mixture goes to a settler where the organic and aqueous phases separate. The organic solution returns to the extraction circuit to load more copper, thus repeating the cycle.

 

The strip solution is pumped to the tank house where the copper is electrowon (electroplated). This solution then returns to the extraction circuit to repeat the cycle. Direct electrical current is applied to the electro winning solution in the tank house. A copper starter sheet functions as the cathode, and additional copper deposits on the surface of the sheet. When the copper cathode has reached a certain size it is removed from the electro winning tank, washed, and prepared for sale. The cathode will be copper of greater than 99% purity.

 

 

·       Flocculants:

 

PICTURE

 

CUC-chem developed the Tramfloc series flocculants, produced in USA over 17 years ago and has remained the premier supplier for mining industry. Our flocculants are constantly improved to better meet the industry's requirements. Tramfloc® AR 192 Series is the latest advancement in flocculants chemistry for the industry.

 

We offer a variety of flocculant technologies to meet the industry's changing needs today and in the future, including anionic, nonionic and cationic flocculants, for optimum performance in many types of applications. Specialized flocculants for the alumina industry and high performance flocculants for the processing of copper and other metals are also part of the product portfolio.

 

 

·       Frothers:

 

PICTURE

 

CUC-chem AR ® frothers include a wide range of products that are either alcohol based, glycol-based or blends formulated for optimum effectiveness in all types of flotation systems. This complete line of products, in conjunction with our unique collector/depressant chemistries together provide all of the tools for optimized flotation processes. In addition, CUC-chem can take advantage of Minefloc MS 100, a holistic approach to mineral flotation optimization combining our 17 years of experience in flotation, unique chemistries, and our application expertise and insights to consistently deliver measurable improvements in operational performance of the frothers.

 

CUC-chem frothers include a wide range of products that are either alcohol, glycol-based or blends formulated for optimum effectiveness in all types of flotation systems. This complete line of products with our unique collector/depressant chemistries provide all of the tools for optimized flotation processes.

 

Froth Flotation

 

Froth flotation is considered to be the most widely used method for ore beneficiation. In ore beneficiation, flotation is a process in which valuable minerals are separated from worthless material or other valuable minerals by inducing them to gather in and on the surface of a froth layer. Sulfide and non-sulfide minerals as well as native metals are recovered by froth flotation.

 

Other chemicals are used to generate the froth and still others are used to adjust the pH. Certain chemicals are even capable of depressing the flotation of minerals that are either to be recovered at a later time or are not to be recovered.

 

PICTURE

 

The process of froth flotation entails crushing and grinding the ore to a fine size. This fine grinding separates the individual mineral particles from the waste rock and other mineral particles. The grinding is normally done in water with the resultant slurry called the pulp. The pulp is processed in the flotation cells, which agitate the mixture and introduce air as small bubbles.

 

PICTURE

 

The ability of a mineral to float depends upon its surface properties. Chemical modification of these properties enables the mineral particles to attach to an air bubble in the flotation cell. The air bubble and mineral particle rise through the pulp to the surface of the froth or foam that is present on the flotation cell. Even though the air bubbles often break at this point, the mineral remains on the surface of the froth. The mineral is physically separated from the remaining pulp material and is removed for further processing.

 

Frothers - ARfom® AR series frothers:

 

Frothers are liquids that produce the froth or foam on which the flotation process depends. The froth resembles soap suds and provides the physical separation between the mineral(s) floated and the pulp containing the waste. The froth must be strong enough to support the weight of the mineral floated and yet not be tenacious and non-flowing. It should have the tendency to break down when removed from the flotation cell. The frother should not enhance the flotation of unwanted material. Many other characteristics are required for a foaming agent to be a good flotation frother. Typical frothers include:

 

o   pine oil

o   certain alcohols

o   low molecular weight polypropylene glycols

 

 

·       Depressants:

 

Depressants are chemicals that inhibit the flotation of minerals. They are used to improve the selectivity of a flotation process. They often make it feasible to separate minerals that were initially floated together.

 

The response of many minerals to the flotation process is often dramatically affected by pH. Flotation circuits are often operated at a pH range of 7.5 to 11.5. The exact range at any given plant is optimized for the ore at that site. Lime is often used to raise the pH of the pulp and also reduce the flotation of iron pyrite.

 

PICTURE

 

Depressants make it possible to increase final recovery consistently without sacrificing concentrate grade. They can either depress the effect of hydrophobic gangue minerals in the ore that would otherwise report with the froth along with the desired mineral or hold down the desired mineral while floating the undesirable gangue. CUC-chem has developed highly efficient and versatile sulfide mineral depressants in diverse applications. In the Cu-Mo separation system, the CUC-chem® AR 200 brand of depressants assists in the depression of copper and iron sulfides at lower dosages than traditional depressants such as NaHS and Nokes reagent.

 

Other applications of depressants include the flotation of simple metal sulfide and complex polymetallic bearing ores, where we provide products that depress iron sulfides such as pyrite and marcasite. CUC-chem also offers products for the depression of magnesium silicates such as talc, pyrophyllite, serpentines, olivines and pyroxenes.

 

 

·       Dust Control Agent:

 

PICTURE

 

Unpaved mine ramp and haul roads produce excessive dust causing many health and safety hazards for employees and residents.

 

CUC-chem AR 300 dust control agent binders are dust control agent and a polymeric soil stabilizer. It serves as a suppressant of nuisance dust generated during the transport of dry material created from dry, windy conditions. In addition, it functions to reduce and eliminate surface erosion caused by wind and rain. At low treatment levels, CUC-chem AR 300 binders works as an effective binding agent which also forms a surface film coating when used in higher concentrations.

 

Collectors - ARfom® AR 400 series collectors:

 

A collector is a chemical that attaches to the mineral surface and produces a hydrophobic (water-fearing) surface. While certain minerals are naturally hydrophobic and do not require a collector, recovery is often improved when a collector is used. This water-repellent film facilitates the attachment of the mineral particle to the air bubble. Many different chemicals are used as collectors, such as:

 

o   oils

o   xanthates

o   dithiophosphates

o   petroleum sulfonates

o   fatty amines

 

Particle Size

 

The particle size to which the ore is ground depends on the nature of the ore. The grind must be fine enough to liberate the mineral grain from associated rock, but producing too small a particle size is both expensive and detrimental to recovery. Froth flotation is generally limited to size fractions between roughly 65 and 100 mesh. Particles larger than 65 mesh Tyler (210 micron) are difficult for the air bubble to lift while particles smaller than 400 mesh (37 micron) often will not attach to the air bubble.

 

Reagent Dosage Rate

 

Many factors influence the amount of reagent required for a particular application. Variations in particular size, mass of particle, quantity of mineral, and the character of the host rock are some of the many factors that influence reagent usage. Water quality, flotation equipment size and type, temperature, and ore body variation are just a few of the variables affecting the flotation process.

 

 

·       Copper/Molybdenum Ore:

 

PICTURE

 

The figure above is a simplified flow sheet showing the basic steps involved in a copper mill producing the byproduct molybdenum. The crushed copper ore (containing, for example, 0.75% Cu and 0.015% Mo) is fed to the grinding circuit where water is added and the ore is ground to the proper size. Lime and an oil for collecting molybdenum are usually added in the grinding circuit. A copper collector may also be added at this point.

 

The pulp progresses to the flotation cells. The frother and copper collector are usually added to the pulp just before the roughers. Additional copper collector is often added to the scavenger flotation cells and may be added at several other points. The froth, enriched in copper and molybdenum, is removed from the flotation roughers and scavengers. This enriched material is now called the rougher concentrate or cleaner feed. The combined rougher-scavenger concentrate may be 5% Cu and 0.06% Mo (a concentration factor of 3 to 10 times is typical).

 

The scavenger or combined rougher/scavenger concentrate may go to regrind where it is ground to further liberate the minerals. The rougher and scavenger concentrates ultimately reach the copper molybdenum cleaners. The cleaners, which represent another cycle of froth flotation, provide additional cleaning and upgrading of the rougher scavenger concentrate.

 

The concentrate, which is now approximately 30% Cu and 0.35% Mo, is pumped to the molybdenum plant where the molybdenum disulfide is separated from the copper sulfide. Chemicals referred to as depressants are added to the pulp to reduce the flotation of the copper minerals while allowing the molybdenum minerals to float. The tailings from the molybdenum plant are the final copper concentrate (typically greater than 30% copper). Following molybdenum rougher flotation and several stages of cleaning, a final molybdenum concentrate is produced. The final molybdenum concentrate is typically greater than 55%.

 

 

·       Lead/Zinc Ore:

 

PICTURE

 

Lead and zinc often occur in the same ore. Copper is also present in some ores. Froth flotation is again employed to produce marketable concentrates of both. The process is identical in principle to the flotation of other minerals. The figure on the right is a simplified version of a Pb/Zn flotation circuit. The main difference in lead/zinc flotation is that zinc is usually depressed while lead (and copper) is floated. The tailing from the lead flotation circuit is the feed to the zinc circuit. The ability to selectively float the separate minerals depends on the ore, the chemicals, and other factors.

 

Conclusion

 

Gold, silver, copper, lead, zinc, molybdenum, iron, potash, phosphate, and even sand for glass are often processed by froth flotation. Without froth flotation, many of the metals and minerals used every day in our modern world would be much more expensive.