Normally Sodium-type Bentonite drying begins with the bentonite being placed in large stockpiles with a moisture content of 30% or higher.  The bentonite is then tilled with a farm tractor and a disk to reduce moisture content and break large chunks into a workable size, a process know as field drying.  Depending on the season and weather, the moisture content would typically be reduced to approximately 25% using this method, which is dependent on hot dry summer days to be effective.

The above is the same regardless of coal or sun drying.   At this point in the process, the difference begins.  Coal fired dryers are used for two reasons: to allow for year round operation without storing large volumes of finished product and more importantly, to dry it quickly.  Coal fired drying can reduce the the moisture content to less than 10% in minutes; sun drying takes days even during the best conditons to reach a similar moisture content.  

To achieve this rapid drying, coal fired dryers reach temperatures in excess of 1300 degrees fahrenheit.  This flash drying superheats the bentonite, which degrades the quality of the clay.  The most obvious change is that the normally soft texture of bentonite becomes hard to the touch.  Also, it reduces the clumping ability and degrades the quality of the clay.

Conversely, sun drying removes a similar amount of moisture without damaging the bentonite clay.  The process is long but simple.  The clay continues to be turned using a farm tractor and disk as in field drying.  We have also developed several secret innovations that naturally aid the drying process, which we will leave to your imagination.

Turning is usually done several times on hot days.  Due to the moisture content the clay is a dark color when stockpiled.  This aids in the drying process as the dark color causes the clay to absorb millions of natural BTUs of the sun's rays, while the arid wind sweeps the evaporated moisture away.  The clay never exceeds 120 degrees Fahrenheit so the quality is not degraded.   The clay is ready to be turned when the dark color vanishes and becomes a greyish white.  This is done for several days until the change in color is nearly unnoticeable.  The dry clay is removed and the process is repeated.

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