Beneficiation Process For Removing Impurities From Feldspar

Feldspar ores are key raw materials for the ceramic and glass industries and often contain impurities that must be removed to improve their quality. Feldspar is frequently associated with other minerals, such as quartz and mica, making selective separation a complex task. Impurities can affect the quality and characteristics of the final product, reducing its value and usefulness. By removing impurities such as iron oxide and titanium dioxide, feldspar can achieve higher purity, making it suitable for a broader range of industries such as ceramics, glass making, and other industrial applications.
These impurities can increase equipment wear in feldspar ore beneficiation, leading to higher maintenance costs and shortened equipment life. Removing iron impurities helps protect processing equipment and maintain its operating efficiency. Its purification process involves a variety of technologies, such as magnetic separation, flotation, acid leaching, or combined processes to achieve the required purity level.

About Feldspar Mineral Information

Feldspar is an aluminum silicate mineral containing calcium, sodium, and potassium. There are many kinds of it, such as albite, anorthite, barium feldspar, barium feldspar, microcline, orthoclase, feldspar, etc. It is widely used in ceramic blanks, ceramic glazes, fireproof calcium silicate boards, the glass industry, and enamel industry, abrasive grinding tools, etc. The beautiful color can be used as decorative stones and secondary gemstones. In addition, feldspar can also be used to make potassium fertilizer; better quality feldspar is used to make television imaging glass bulbs, etc.

Process for removing impurities from feldspar ore

  • Iron oxide is one of the main impurities that is usually eliminated, which gives the feldspar a reddish hue and reduces its quality. Iron oxide can be effectively separated from feldspar ores through magnetic separation or flotation.
  • Another impurity that often needs to be removed is titanium dioxide, which can also affect the color and clarity of feldspar. To solve this problem, various purification methods, such as froth flotation or high-intensity magnetic separation, are used to extract titanium dioxide from the ore. In addition, other impurities, such as mica and quartz, can also be eliminated during the processing stage to improve the overall purity and quality of the feldspar product.

Feldspar Ore (Impurity Removal) Beneficiation Process

1. Magnetic separation process

The magnetic separation process mainly uses the different magnetic properties of the iron minerals in the ore to formulate corresponding magnetic separation processes, which can remove most of the highly magnetic ores. However, for some highly weathered ores, the iron minerals are prone to muddying during the grinding process. , it is difficult to remove this part of iron minerals with strong magnetic separation.
For weakly magnetic minerals such as iron oxide, mica, and garnet in feldspar ores, strong magnetic separation should be used for separation. The selection of magnetic separation equipment needs to be determined based on the properties of the ore. Commonly used magnetic separation equipment include wet cylindrical magnetic separators, vertical ring pulsating high gradient magnetic separators, and flat plate magnetic separators.

2. Flotation process

The flotation process can effectively remove iron from clay and fine-grained iron-containing minerals, but the effect is not good for hard ores. For severely weathered ores, secondary sludge may be produced during the crushing and grinding stage, which may easily cause the flotation foam to be highly viscous, resulting in reduced collector selectivity and poor effectiveness. In addition, when the iron-containing impurities in the feldspar are iron-containing alkali metal silicate minerals such as pyrite, mica, garnet, tourmaline, and hornblende, flotation is often used to remove the impurities. The conditions for flotation to remove feldspar impurities are as follows:

  • Sulfide ore is removed by flotation using xanthate collector under the natural pH conditions of the slurry;
  • Mica minerals can be removed in an amine collector system with a slurry pH of 2.5-3.5;
  • For silicate minerals, when the pH of the pulp is 3-4, a sulfonate collector can be used to separate them to the surface.
Beneficiation Process For Removing Impurities From Feldspar

3. Magnetic separation-flotation combined process

For some difficult-to-select feldspar ores, not only the iron content is high, but also some impurities penetrate into the cleavage gaps of the feldspar in the form of iron staining. First, most of the iron minerals are removed through magnetic separation, and then the fine-grained iron minerals and iron-dyed feldspar are removed by flotation. The feldspar concentrate has a much lower grade of iron than a single magnetic separation, and is much lower than a single flotation concentrate. The grade is also low, and the yield is close. Dry magnetic separation first and then flotation can get the best separation effect. However, in industry, dry magnetic separation requires dehydration and drying, which is relatively expensive, so wet magnetic separation first and then flotation. The selected process is more widely applicable.
With the decrease of high-quality feldspar resources, low-grade feldspar has become the main resource for feldspar ore processing. In addition, downstream enterprises have increasingly higher requirements for the grade of feldspar concentrate, which will inevitably put forward new requirements for the processing of feldspar ore. Due to the high requirements, a single mineral processing and purification process can no longer meet the needs of the market. The use of multiple separation operations, such as desliming, magnetic separation, flotation, etc., to form a combined process will become the main way to process feldspar ore.

4.Acid leaching process

The acid leaching process is a method that uses acid to selectively dissolve iron-containing minerals and remove iron from feldspar. It is an effective method to treat feldspars containing extremely fine impurities embedded in the crystal structure. Commonly used acids include hydrofluoric acid, hydrochloric acid, sulfuric acid, nitric acid, oxalic acid, etc.
The acid leaching process can very well deal with ores that are severely weathered and prone to sludge after grinding. The acid leaching process has high iron removal efficiency, but the acid leaching waste liquid contains a large amount of iron, aluminum, potassium, magnesium and other metal ions, which must be processed After treatment, it can be discharged only after it meets the national emission standards.

Compared with traditional flotation processes, magnetic separation of feldspar ores is more efficient in some cases and provides a more environmentally friendly method. By exploring flotation, magnetic separation, acid leaching and other methods, mining companies can optimize their operations, reduce waste and improve the purity of feldspar products, ultimately leading to higher quality end products for various industries. JXSC will customize the feldspar mineral processing technology and equipment for you to help you obtain the ideal mineral processing technology and equipment.