Roller mill.

摘要

Raw coal (1) is caused to fall through a coal feed pipe (2) on a table (3) and pulverized by a roll, fine coal particles (5) and coarse coal particles (6) resulting from pulverization are moved upward between an auxiliary classifier cone (7) and a mill casing (19) by means of hot air (4) supplied from below the mill casing (19), the hot air (upward stream) carrying fine coal particles (5) and coarse coal particles (6) moves across a space of triangular cross section formed between the inverted conical body of the auxiliary classifier cone (7) and the mill casing (19) and flows through blowoff openings (8) defined between deflector plates (9) so that it is changed to a lateral rotative stream toward a rotary classifier (11), upon impinging on downward-inclined rotating vanes (10) of the rotary classifier (11), coarse coal particles (6) are sprung back toward a lower portion of the auxiliary classifier cone (7) and separated from fine coal particles (5), and fine coal particles (5) separated from coarse coal particles (6) are ejected together with the upward stream through a pulverized-coal eject pipe (12) out of the roller mill. Coarse coal particles (6) sprung back toward the lower portion of the auxiliary classifier cone (7) move along the inner surface of the auxiliary classifier cone (7) and fall on the table (3) so that they are re-pulverized by the roll. <IMAGE>