Feldspar is the most important rock forming mineral of surface rock. Potassium or sodium feldspar rich in potassium or sodium is mainly used in ceramic industry, glass industry, enamel industry, abrasive grinding tools, chemical and electric welding industries.
Potassium sodium feldspar impurity
The content of iron and calcium in the potassium sodium feldspar determines the advantages and disadvantages of the ceramic products. The iron content is too high, the burnt products will appear black spots. The content of calcium (mainly in carbonate) is too high, and the sintered products will appear bumpy pores. Therefore, the content of iron and calcium must be reduced in the process of feldspar purification. There are two main forms of iron existence, one in free minerals such as hematite, two in mica minerals, and calcium in calcite, and hematite can be removed by high gradient magnetic separation. The mica minerals can be removed by high gradient magnetic separation and flotation. Calcite is mainly floated by floatation. Choose to remove.
Mineral processing method of potassium sodium feldspar
At present, the main sources of potassium and feldspar are pegmatite, fine-grained rock, weathered granite and feldspar sand. For different sources of potassium and sodium feldspar, different mineral processing methods are generally adopted.
1. Vibrite is generally selectively mined or hand-selected, dry processing. Raw mine → rough crushing → fine crushing → grinding → strong magnetic dressing / static dressing → grading → packaging → product.
2. Weathering granite. For mica leavers, only water washing and screening are required; Among mica containing mica, mica and iron minerals are removed and feldspar and quartz are separated by flotation after fragmentation and grinding.
3. Most of the fine crystal rocks that meet the industrial requirements do not contain mica. When the feldspar content is high, it is only necessary to break, grind, sieve, and magnetic separation of iron.
4. After semi-weathered granite is broken by a jaw Crusher, a cone Crusher, and a gravel mill, the mica, iron minerals are first picked up, and the feldspar is picked up and separated from quartz. A similar method can be used for the selection of feldspar sand ores.
Technical requirements for purification of potassium sodium feldspar
1. The grinding of feldspar is mainly divided into two types: dry grinding and wet grinding. Relatively speaking, wet grinding efficiency is higher than dry grinding and is not prone to "over grinding" phenomenon. In order to avoid iron impurities in the grinding process, the grinding process of feldspar ore generally does not use iron medium grinding, mostly using stone wheel rolling, intermittent gravel or porcelain ball milling.
2. Desliming on the one hand reduced the content of Fe2O3 in feldspar and increased the content of Na2O and K2O; on the other hand, it removed the primary slime and secondary slime produced by grinding. The method of hydraulic sedimentation can be used for desliming, or the negative combination of mud and sludge will give priority to the combination of flotation reagents and floatation agents or collectors.
3. The iron minerals, mica and pomegranates in the feldspar have some magnetic properties, while the feldspar has no magnetic properties. Therefore, the separation of feldspar and magnetic minerals can be realized under the external magnetic field. Because of the low magnetism of iron minerals, mica and garnet, it is usually necessary to use strong magnetic separation equipment to remove them effectively. At present, the main magnetic separator used in China are high gradient strong magnetic separator, permanent magnet roll type strong magnetic separator, wet flat ring strong magnetic separator and permanent magnetic cylinder type medium and strong magnetic separator.
4. The potassium sodium feldspar is generally symbiotic with mica, quartz, calcite and iron bearing minerals. In general, the iron in the feldspar minerals is mainly included in mica, hematite, pyrite and ferric alkali metalilicate minerals (such as garnet, tourmaline and amphibole). Flotation is one of the effective ways to remove harmful impurities from feldspar. Feldspar can be floatation with oleic acid collector. Aluminum salt inhibits feldspar in acidic medium and activates feldspar in weak alkaline medium. Amine is also a collector for feldspar, and the effect is good. But we should pay attention to the adjustment of slurry pH and the release of mud.
Equipment for potassium sodium feldspar purification
Breaker equipment: jaw Crusher, cone Crusher / roll Crusher
Grading equipment: vibration sieve, hydraulic classifier / hydrocyclone, airflow classifier
Grinding equipment: ball grinder, gravel grinder
Ore dressing equipment: high gradient magnetic separator, flotation separator
Drying equipment: filter press, dryer
Packaging equipment: baler
Profit of potassium sodium feldspar purification
The market price of potassium sodium feldspar powder for ceramics is about 400 yuan/ton, the price of the original stone is about 100 yuan/ton, and a small potassium sodium feldspar processing plant with a daily output of 500 tons requires about 1 million ore processing equipment. Excluding production costs, it can make nearly 10 million profits annually.