Dry Mill Rejects Handling in PCF Power Plants
MRS® - Magaldi Mill Rejects System

The MRS® (Magaldi Mill Rejects System) is a new process concept designed to mechanically handle rejects from coal mills, in a dry way.
Rejects are a mixture of different materials (pyrites, stones, tramp iron, etc.) with pulverized coal, requiring a reliable and safe removal system.
Discharged from coal mills, the rejects are collected in pyrite boxes for temporary storage. The material is extracted from the pyrite boxes by MRS® extracting conveyors or vibrating feeders and then dosed onto the main MRS® conveyor, which collects the rejects produced by all the coal mills. Downstream the main MRS® conveyor, the rejects can be discharged onto a movable container or into a storage silo.
The MRS® easily accommodates an increase in rejects and coal rate (for example during mill trip) without creating any fire or explosion hazard.
In addition to the Superbelt® technology, the MRS® reliability is also guaranteed by the “open execution” design that allows:

• visual inspection while protecting operators from accidental contact with moving parts. On the contrary, in a closed machine, the inspection cannot be carried during the operation due to the potentially explosive atmosphere (EN 13463-1);
• fire and explosion risks reduction. In a closed machine, the coal dust settles on the bottom of the casing, thus increasing the risk of fire/explosion. The MRS® system allows the continuous monitoring of dust accumulation and includes (optionally) a dedusting system with consequent further reduction of fire risk;
• simpler design. A closed machine, with an explosive atmosphere inside, must be designed for an overpressure of 3.5 bar or higher. This prescription is not required for the Magaldi MRS® system thanks the “semi-open” execution.