A leading international supplier of flame retardant chemicals, in expanding it's European capacity, chose Atritor Ltd, Coventry, England as it's main supplier of the drying, de-agglomeration & powder classification plant, based on Atritor's Cell Mill-Dryer-Classifier technology.

The key to Atritor's success in the face of hard international competition, was the Cell Mill-Dryer's low residence time, high energy operation, which gives such a high degree of de-agglomeration to ensure that the particle size distribution is easily adjusted for the application. Also, because of the nature of Atritor's Cell Mill-Dryer integral classifier unit, coarse particles can either be returned to the mill body for further size reduction or rejected completely at certain points in the process, where hard flakes might be  formed  during  the   reaction.

This facility gives the producer increased flexibility.

Cell Mill-Dryer technology also gives the customer the opportunity to feed the wet precipitate as either a press cake or as a water based slurry, the latter being sprayed into the dryer body direct, where moisture is instantly flashed off while the suspended particles are kept apart as they migrate upward in the highly turbulent gap between the rotor and the serrated body liner. Although most coating is completed in the wet phase prior to drying, the customer was also impressed by the Cell Mill-Dryer's high integrity particle coating capability, by injecting the coating - wet or dry - into the mid body of the unit.

All told, the Atritor solution gives maximum flexibility in a relatively small package, when compared to separate drying, milling & classification process steps, still in use in some plants.

Atritor's package, with all contact parts in stainless steel, included a special agitated live hopper feed unit to deal with a sticky wet cake of colloidal precipitate, an air heater package for 20,000 m³/h hot air to the dryer, a CM1250-IC 132kW Cell Mill-Dryer including an integral 30kW classifier unit with recycle / reject reversible screw system, a cylindrical reverse pulse product collection filter, discharging via a rotary valve into a product cooling/conditioning screw, a pneumatic conveying system to distribute the products to storage, a system fan and full ductwork and transitions supply. Atritor designed, built, mechanically installed and commissioned the complete system.