Soda Feldspar Washing Plant Equipment and Process

Soda feldspar is a key raw material widely used in glass manufacturing, ceramics, and the chemical industry. However, raw soda feldspar ore often contains impurities such as quartz, mica, and iron-bearing minerals. To effectively increase the Al₂O₃ content and reduce impurity levels, ore washing is a crucial step in the beneficiation process.

When designing a soda feldspar washing plant, Xinhai Mining fully considers the equipment compatibility and process integration. The resulting process flow is highly efficient, energy-saving, and features a high degree of automation.

01Key Equipment for Soda Feldspar Washing Plant

In the processing of soda feldspar, there are three main challenges in the beneficiation process:

The physical properties of soda feldspar and potassium feldspar are similar, making separation difficult;

It is challenging to remove fine-grained clay minerals;

Efficient removal of impurities such as iron and titanium remains complex.

To overcome these challenges, the key equipment in a soda feldspar washing plant includes:

1. Crushing and Grinding Equipment

Jaw Crusher: Used for the primary crushing of soda feldspar ore, reducing the particle size to below 100 mm. Hydraulic jaw crushers are recommended for their large reduction ratio and low energy consumption.

Cone Crusher: Responsible for secondary and tertiary crushing, further reducing the ore to below 30 mm. The laminated crushing principle ensures a more uniform product size, which is suitable for medium-hard ores like soda feldspar.

Ball Mill: The crushed ore is sent to a ball mill for wet grinding to a fineness of -200 mesh. Since iron impurities can significantly affect concentrate quality, it is advisable to use rubber linings in the ball mill to minimize iron contamination.

Classification Equipment: Ball mills are often paired with hydrocyclones or spiral classifiers to form a closed-circuit grinding and classification system.

2. Beneficiation (Sorting) Equipment

Trough Scrubber:

Used to remove surface-attached clay, fine mud, and other impurities, especially effective for weathered feldspar ore. Through impeller stirring, it peels off surface clay, achieving over 85% desliming efficiency on high-mud ores.

Magnetic Separation Equipment:

Permanent Magnetic Drum Separator: First-stage separation, with a magnetic field strength of 0.1–0.3 T, for removing strongly magnetic minerals.

Wet High-Gradient Magnetic Separator (HGMS): Second-stage fine separation, with 1.0–1.5 T field strength, to remove weakly magnetic minerals such as hematite and ilmenite.

Flotation Equipment:

Used to remove gangue minerals such as quartz and mica.

For quartz separation: Adjust pH to acidic, use hydrofluoric acid as an activator and amine collectors to float feldspar while inhibiting quartz.

For mica separation: Adjust pH to alkaline and use cationic collectors to float mica.

Equipment recommendation: Use KYF flotation cells for roughing and scavenging, and flotation columns for cleaning to improve concentrate grade.

Photoelectric Sorter:

Applied to separate potassium feldspar from soda feldspar based on differences in color and reflectivity. Using high-speed air valves, it achieves sorting accuracy over 90%.

3. Dewatering and Drying Equipment

Thickener and Filter Press: After sorting, the concentrate pulp is thickened to about 50% solid content using a thickener and then dehydrated by a filter press to reduce the moisture content to ≤15%.

Rotary Dryer: Finally, a rotary drying kiln reduces moisture to below 5%, ensuring ease of transportation and storage.

02Soda feldspar Washing Plant Process Flow

According to the ore type and impurity composition, soda feldspar can be divided into two main types:

(1) coarse-grained weathered ore and

(2) fine-grained disseminated ore.

Below is a typical process flow for treating each type.

1. Coarse-Grained Weathered Ore

Process Flow:

Soda feldspar ore → Jaw crusher (crushed to ≤50 mm) → Drum ore washing screen (with water flushing and screening) → Trough scrubber (clay removal) → Spiral classifier (desliming) → Dry magnetic separator (for removal of strongly magnetic iron minerals) → Concentrate dewatering → Final product

This process relies primarily on physical cleaning methods, features low equipment investment, and is suitable for the preliminary treatment of low-grade ores.

The typical concentrate quality can reach:Al₂O₃: 20–22%;Fe₂O₃: 0.5–0.8%.

2. Fine-Grained Disseminated Ore

Process Flow:

Albite ore → Jaw crusher → Cone crusher → High-pressure grinding roller (HPGR) (to ≤3 mm) → Ball mill (80% passing -200 mesh) → Hydrocyclone classification → Desliming (removal of fine particles <10 μm) → High-gradient magnetic separation (removal of iron and titanium impurities) → Flotation (HF activation of albite; reverse flotation of quartz) → Thickening → Filter press → Drying → Final concentrate

This process integrates magnetic separation and flotation, requiring precise control of pH levels and reagent dosage.

The final concentrate meets high-end ceramic raw material standards, with specifications of:Al₂O₃ ≥ 26%;Fe₂O₃ ≤ 0.3%.

03Soda feldspar Washing Plant Project Case

The soda feldspar washing plant project undertaken by Xinhai Mining is located in Hebei Province, China. The main valuable minerals are soda feldspar and potassium feldspar, with a combined content of 60–80%.

The major gangue minerals include:Quartz (10–30%);Biotite (1–5%);Muscovite (1–5%). With trace amounts of magnetite and tourmaline.

Crushing and Grinding Stage

The crushing circuit adopts a two-stage closed-circuit process, consisting of a jaw crusher and circular vibrating screen for primary crushing, followed by a cone crusher for secondary and fine crushing.

The grinding and classification stage adopts a two-stage closed-circuit grinding process:

A grate-type ball mill and spiral classifier are used for coarse grinding

An overflow-type ball mill is used for fine grinding

Separation Process

The separation operation involves three key steps:

Medium-intensity magnetic separation

Desliming

Reverse flotation

A magnetic separator is first used to remove magnetite impurities.

The magnetic tailings are sent to a desliming tank to eliminate fine clay particles.

After desliming, the slurry is sent to a mixing tank, where it is thoroughly mixed with reagents, and then pumped to the XCF/KYF flotation unit for reverse flotation, effectively removing iron oxides and mica.

The concentrate is then dewatered using a hydrocyclone and dewatering screen.

Project Results

Feldspar concentrate yield: 73.37%;Annual output: 87,972 tons of high-quality feldspar concentrate

Conclusion

This project highlights the key equipment and typical process flow involved in a soda feldspar washing plant.

With over 30 years of experience in the mineral processing industry, Xinhai Mining has undertaken thousands of feldspar beneficiation projects, accumulating a wealth of practical knowledge.

The mineral processing plants designed and constructed by Xinhai feature:High automation and intelligence levels;Advanced manufacturing technology;Concentrate grades of Al₂O₃ ≥ 26%, Fe₂O₃ ≤ 0.3%;Recovery rates exceeding 85%, meeting or exceeding industry-leading standards.

If you are looking for an efficient and reliable solution for soda feldspar beneficiation, feel free to contact us for customized support.