Bentonite is an absorbent aluminium phyllosilicate, generally impure clay consisting mostly of montmorillonite. There are different types of bentonites and their names depend on the dominant elements, such as potassium (K), sodium (Na), calcium (Ca), and aluminum (Al).
Bentonite usually forms from weathering of volcanic ash, most often in the presence of water. However, the term bentonite, as well as a similar clay called tonstein, have been used for clay beds of uncertain origin. For industrial purposes, two main classes of bentonite exist: sodium and calcium bentonite.
Bentonite crusher is a type of stone crushers that is used to crush Bentonite. Bentonite is the raw materials for construction, road, bridge and railway buiding and small gravel are also important for the manufacture of concrete. Bentonite has all kinds of shape and size. So it is not suitable for buiding material. Bentonite crusher can crush native rock into all kinds of size to create Bentonite for use in the concrete for the dam and other buiding. Bentonite crusher is the esssential mining and construction machine. And you can grind the bentonite into powder with bentonite grinding mill.
Bentonite haw wide using application fields
* Because of its good physical and chemical properties, do binder, suspending agent, thixotropic agent, stabilizer, purification bleaching agent, filling material, feed, catalyst, etc., bentonite are widely used in agriculture, light industry and cosmetics, medicine and other fields.
* Bentonite can be used in cement, adhesives, ceramic bodies, and cat litter. Bentonite is also used as a binding agent in the manufacture of taconite pellets as used in the steelmaking industry.
* The ionic surface of bentonite has a useful property in making a sticky coating on sand grains.
* The same effluvial deposition of bentonite clay onto beaches accounts for the variety of plasticity of sand from place to place for building sand castles.
Bentonite Grinding mill
The bentonite must be grinded into bentonite clay powder before furture processing. The most suitable bentonite Grinding mill is SBM YGM high pressure Grinding mill.
High pressure Grinding mill, widely using in metallurgy, building materials, chemical, mining and other mineral materials' grinding process, can make a wide range of final product particle size in grinding bentonite, whose thick size is up to 0.95 mm (20 mesh) and thin size is up to 0.038 mm (400 mesh). Compared with the common Raymond Grinding mill under the same power conditions, the capacity of YGM high pressure Grinding mill can be increased by 10%; moreover, under the performance of high-pressure springs, the rollers grinding pressure on raw materials can be raised by 800-1200kgf. Its dust-removing effect fully meets the national dust discharge standard and its classifier is easy for adjustment.
SBM also supplies other Grinding mills, which can be used in bentonite grinding process. These Grinding mills include ball mill, LM vertical mill, Raymond mill, MTW trapezium mill and so on.
In the early years, all naturally occurring activated clays having good bleaching properties were called fuller's earths. The word fuller's earth has been named after the practise of fulling or cleaning the grease and stains from wool and cloth.
The essential difference between bentonite and fuller's earth is in their modes of occurrence and other physical properties. Bentonite is regarded to have been formed by the alteration of volcanic ash deposits, mostly in upper Cretaceous formations. Fuller's earth represent a shaly facie of Tertiary rock. Two types of bentonite are generally identified. One is called the swelling type or sodium bentonite, which has single water layer particles containing Na+ as the exchangeable ion. The other has double water layer particles with Ca++ as the exchangeable ion. It is called calcium bentonite or non-swelling type. Na+ or Ca++ is exchanged by Mg++ or Fe++. A third type of montmorillonite has been identified with zero water layer particles and is probably electrostatically neutral. Calcium bentonite is usually referred to as fuller's earth by a number of authorities because chemically and also in physical properties it is identical to calcium-montmorillonite.
Bentonites having low iron content, have been found to be good catalytic agents in petroleum refining. The bentonites having Ca and / or Mg as exchangeable ions are good decolourizers. Bentonites can absorb water to a greater extent than ordinary plastic clays. Fuller's earth, on the other hand, is non-plastic or semi-plastic in character. It has a foliated structure. Dry or dehydrated fuller's earth adheres strongly to the tongue. The absorption of water in sodium bentonite proceeds with a considerable increase in volume (as much as 14 times its original volume) creating an excellent gel and viscous material which is invaluable for the preparation of drilling muds and in grouting of dams, wells etc. Sodium bentonite has an excellent thixotropic property, i.e. the gel becoming stiff on standing and reverting to fluidity when shaken. The swelling type bentonite when dispersed in water, separates into suspendible flakes which are all finer than 0.5 micron. Calcium bentonite yields about 35% finer than 0.5 micron. Calcium bentonite yields about 35% finer than 0.5 microns. The difference in bentonite and other clays lies in lattice structure. The sheet of atoms in bentonite are much thinner and more easily separable in water. That is why bentonite occupies more surface area than other clays. This property is known as dispersibility, which is unique to swelling type of bentonite.