Wet or slurry process
The wet or slurry process uses the same primary and secondary crushers as the dry process. However, rather than a blend of raw clays being loaded into the primary crusher, raw clays are placed in a batch hopper in a certain order so that different clays enter the process first for each batch. These are then fed into a blunger via conveyor belt. The blunger contains hot water and predetermined chemicals, depending upon the product being made. Clays loaded first react with the chemicals to enable the digestion of organics and lignins which form part of their composition. Other clays follow as determined and required. The blunger mixes for a programmed period of time. Control checks are made to test gravity and carry out screen analysis.
The material is then transferred to 0.06 mm scalper screens. From there it is pumped over several 0.175 mm finish screens, put through a ferro filter and moved into a storage tank where it is examined.
After checking its specifications, the material is mixed to increase its consistency for shipping. Products are transported as 61% solids or higher via tank truck or tankcars.