Hydrated lime is a fine white powder that plays a major role in various industries and sectors like metallurgy, construction, water treatment, agriculture, and chemical manufacturing. Such a varying use results from its several properties, like its alkalinity and affordable costs. Among its roles in several different industries, hydrated lime for copper industry tends to be an important material too.

Use of Hydrated Lime in Copper Industry

In today’s time, hydrated lime has a huge purpose to play in metal extraction. This role is also relevant in the copper ore processing and hence in the copper industry as a whole. The following are several processes in the copper industry where hydrated lime is deemed the most effective:

pH Control in Flotation Circuits

During froth flotation, it is used to maintain an alkaline pH. Typically, its pH should be around 9-11, and hydrated lime is added to the flotation circuits to raise and maintain pH at that level. This ideal pH is used to enhance the flotation of copper sulfide minerals like chalcopyrite, which improves copper recovery rates and concentrate quality.

For Unwanted Minerals

Unwanted minerals or gangue minerals are altered by the presence of hydrated lime. These unwanted minerals include pyrite and iron sulfide, whose interaction with collectors is reduced when they are depressed by the hydrated lime. This depression results in cleaner and higher-grade copper concentrates, which in turn reduce smelter penalties and downstream refining costs.

Water Treatment

During ore processing, smelting, and tailings disposal, wastewater is generated, which contains acidic effluents dissolved in it, such as heavy metals, sulfates, and toxic residues. As hydrated lime raises the pH, all such materials are precipitated, which settle out of the water and are removed along with sludge.

Slime Coating Prevention

In fine grinding circuits, very small particles of slime are generated. These slimes coat the surface of ore particles, which then interfere with the action of flotation reagents like collectors. In turn, the flotation performance severely declines. To prevent such a problem, hydrated lime helps in many ways, starting with the pH adjustment due to which slime doesn’t stick to each other or the ore surface. It also promotes flocculation, which makes the slime settle out. 

Tailing Stabilization

Once valuable minerals are separated from the ore, the tailings remain behind. These contain acid-generating sulfides, residue heavy metals, and many toxic compounds, which can cause a lot of harm to the environment. Hydrated lime is used here to stabilize them and make them safe for storage. This stabilization includes neutralizing acidity, precipitating metals, and reducing leachability.

Affordability

Besides all the help the chemical properties of the material provide, cost is also a factor that should be kept in mind. Keeping that in mind, hydrated lime is a very affordable reagent too. It offers a very high functional value at a relatively low cost compared to sodium hydroxide, soda ash, or any other such chemicals.

What makes it so cost-effective is its abundance in nature. Additionally, any effect that other materials produce in a high volume, a comparatively much lower volume of hydrated lime is needed for the same effect. Lime produces a less corrosive environment and has multiple functions in the process of mining, too.

Conclusion

The demand for hydrated lime in today’s time makes it one of the most important materials in the mining and metallurgy industries, more particularly in the copper industry. To fulfill this huge demand, Rajasthan Lime has been successfully serving the customers according to their needs for the last 40 years.

Rajasthan Lime is the leading lime supplier for mining industry in India today. We supply the best quality lime in various sectors like iron steel, copper, paper, and much more.

Frequently Asked Questions (FAQs)

Q. What is hydrated lime?

Hydrated lime is a white, alkaline powder used in mining and metallurgical industries.

Q. What is the use of hydrated lime in the copper industry?

Hydrated lime is used in the copper industry for various purposes like wastewater treatment, tailing stabilization, pH control, slime coating prevention, etc.

Q. Is hydrated lime affordable?

Yes, hydrated lime is more affordable than other chemical reagents used, like soda ash, sodium hydroxide, etc.