Method and apparatus for the two-stage crushing of brittle material for grinding

US4783011A · kind A · utility

Assignee

• Krupp Polysius AG · DE

Inventors

• Gotthardt Blasczyk · Beckum, DE
• Norbert Patzelt · Beckum, DE
• Heinz-Georg Mersmann · Beckum, DE
• Franz-Josef Adrian · Lippetal, DE
• Hardy Kropf · Oelde, DE

Key dates

• Filing date: Dec 10, 1987
• Grant date: Nov 8, 1988
• Expiry date: Dec 10, 2007

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B02C25/00
• WIPO field: Chemical engineering
• WIPO sector: Chemistry

Abstract

A method and apparatus for the two-stage crushing of brittle material comprising a roll mill and a mill connected downstream thereof, the output of the second mill being delivered to a sifter in which a second branch stream of the grit obtained in the sifting operation is returned to the roll mill and a further branch stream is returned to the second mill. A first control circuit keeps the sum of the quantity of fresh material and the quantity of grit constant, while a second control circuit divides the quantity of grit into two branch streams in such a way that the drive power of the roll mill remains constant.