D-logo.gif (3033 bytes)The Dryden Engineering Company (Pty) Ltd.

Up BRICKING SOLUTIONS ATRITOR LIMITED

ATRITOR DRYER-PULVERISER
The Atritor Dryer-Pulveriser.  A long established product for the simultaneous drying and milling of minerals, chemicals, waste materials etc. It is also capable of blending materials and of surface modifying performance minerals. It is a compact flash dryer with a high evaporative capacity and drying efficiency. Inlet temperatures as high as 600deg C are used and evaporatine capacities up to 6000kgs/hour are achievable from a single unit.

ATRITOR CELL MILL
The Atritor Cell Mill.  A recent development of a multi-rotor vertical shaft mill for producing very fine powders by the utilisation of impact, shear and attrition forces. Modular in construction, it can be tailored to the specific need of a project. It can be fitted with an integral classifier for control of product top-size. It is an efficient dryer with inlet temperatures up to 4 00deg C. Special designs are available for the efficient application of surfactants to modify the surface chemistry of products.

ATRITOR DCM MILL
The Atritor DCM Mill (Dynamic Classifier Mill).  A high speed grinding mill with an integral, independently driven dynamic classifier producing a narrow size distribution. The feed first enters the classifier to remove in-specification material before the oversize enters the grinding zone.
INTERNAL FAN ATRITOR

Size reduction occurs in three stages. The material to be processed is delivered to the Atritor by suitably designed feeding equipment and is immediately entrained in the incoming air stream.

It first enters the swing hammer zone where it is reduced from 50mm to 5mm by the action of swing hammers attached to the main rotor centre and operating inside a ring of screens. The lower section of the screen ring provides a receptacle where foreign contaminants in the feed can be rejected. This swing hammer section is omitted for certain applications. Secondary size reduction occurs in the first pulverizing zone of the Atritor by the action of fixed hammers on the main rotor.

Passing over the periphery of the rotor, the material enters the main pulverising chamber where it is subjected to a combination of opposing centrifugal and centripetal forces, superimposed on intensely turbulent air patterns generated by alternate rings of rotating and stationary pegs. As the size of the particle is reduced the centripetal air drag forces become dominant and draw the material towards the size control zone at the centre of the rotor, where rotating rejectors intercept and return larger particles to the attrition zone, whilst permitting the free passage of finer particles from the Atritor. The number of rejectors thus controls ultimate particle size.