Patent Pending Retractable Enhanced Flow Discharge System | Improve Fineness

The Flapper Valves on the MPS and MBF are designed to catch coal that has been rejected at the classifier level. The weight of the accumulated reject coal trips the Flapper Door and releases it for regrind.

Air flow studies show that oversized coal released from the Flapper Assembly is re-entrained into the primary airflow and can be carried back through the classifier to be rejected again, thus short circuiting the classifier process. This increases mill inventory, DP and motor amps. Thus, resulting in reduced capacity. In some cases the Flapper Door sticks open allowing coal to blow back through the door. The Patent Pending SAS Retractable Enhanced Flow Discharge System will eliminate the Flapper Assembly along with the mechanical and operational problems associated with it. 

The illustration below shows the retractable extension lowered from the bottom of the transition cone directly into the heart of the grinding zone. This forces the coal to the center of the bowl for regrind and does not allow it to become re-entrained in the upward airflow. Test have shown an 11-12% improvement in fineness over mills using  old style Flapper Assemblies.