Vertical roller mill
A vertical roller mill provided with a cyclone-type fixed separator that separates fine powder and allows the separated powder to flow out to the outside, the cyclone-type fixed separator being provided inside a housing, wherein the fixed separator is configured so that a solid-gas two-phase flow is introduced from a fixed blade inlet window opening on a cone into the inside and the solid-gas two-phase flow is swirled using a fixed blade attached in the inside vicinity of the fixed blade inlet window, whereby the fine powder flows out to the outside from a pulverized coal outlet in an upper portion of the vertical roller mill through the lower end side of an inner cylinder provided inside the cone, a surface layer in which the rebound coefficient of collided particles is higher than in an iron plate surface being formed in the outer surface of the inner cylinder.
1. A vertical roller mill comprising, in a housing, a fixed cyclone separator configured to separate, when a solid-gas two-phase flow for delivering powder obtained by pulverization of a solid passes through the fixed cyclone separator, fine powder having a small particle size by centrifugal force to flow out to an outside,
wherein the fixed cyclone separator is configured such that after the solid-gas two-phase flow is introduced into the fixed cyclone separator through a fixed blade inlet window opening at a cone-shaped member, the fine powder is flowed out from an upper outlet to the outside by way of a lower end portion of an inner cylinder provided inside the cone-shaped member by swirling the solid-gas two-phase flow by a fixed blade attached to a vicinity of the fixed blade inlet window inside the fixed blade inlet window, and
a surface layer made of copper is formed on a back surface of the fixed blade.