A device for comminuting feed material with first comminuting tools and second comminuting tools, which are arranged inside a housing coaxially to an axis and which are axially spaced apart to form a comminuting zone, and of which at least the first comminuting tools perform a rotational movement about the axis. In a contact area between a first tool carrier and the first comminuting tools and/or in a contact area between a second tool carrier and the second comminuting tools a plurality of channels for the passage of a process gas are provided. The channels each have a radially inner inlet opening through which the process gas enters the channels and a radially outer outlet opening through which the process gas emerges from the channels. Among other things, this achieves improved cooling of the comminuting zone.

The invention relates to a refiner plate segment in a refiner plate for mechanically refining of lignocellulosic material in a refiner, said refiner plate segment comprising at least a first, generally radially extending bar, a second, generally radially extending bar, a groove arranged and defined between said first, generally radially extending bar and said second, generally radially extending bar, and a main dam, which has a height H and is arranged in the groove, wherein a pre-dam is arranged in front of the main dam, said pre-dam has a height h which is less than the height H of the main dam.

The invention describes powders for use in the production of spatial structures, i.e. molded bodies, using layer build-up methods, as well as methods for their efficient production. The powders have the special feature that they have good flow behavior, for one thing, and at the same time, have such a composition that the molded body that can be produced with the powder, using rapid prototyping, has significantly improved mechanical and/or thermal properties. According to a particularly advantageous embodiment, the powder has a first component that is present in the form of essentially spherical powder particles, which is formed by a matrix material, and at least one further component in the form of stiffening and/or reinforcing fibers, which are preferably embedded in the matrix material.

A preparation of niobium nanoparticles, its use, and a process for obtaining it by comminution, that is, a top-down process. The preparation of nanoparticles has a particular composition, purity, granulometric profile, and specific surface area, being useful in a variety of applications. Also taught is a process for obtaining nanoparticles of mineral species containing Niobium, through controlled comminution and without chemical reactions or contamination with reagents typical of the synthesis of nanoparticles. The preparation of niobium nanoparticles provides the large-scale production of niobium pentoxide nanoparticles with high purity, determined granulometric profile and very high specific surface area, enabling its use in practice in several industrial applications.

The present invention concerns a granular material conditioner for optimising grain sizes of granular materials comprising two discs which are rotatable relative to each other and which are arranged in substantially mutually parallel relationship, a granular material inlet through which granular material can be passed into the conditioner into an annular gap between the two discs, and a catch container for receiving the granular material which issues from the gap between the two discs by virtue of centrifugal force. According to the invention it is proposed that the catch container has an elastic curtain, wherein the curtain is spaced at least portion-wise from the catch container wall and limits the trajectory of the granular material issuing from the gap.

The present invention concerns a granular material conditioner for optimising grain sizes of granular materials comprising two discs which are rotatable relative to each other and which are arranged in substantially mutually parallel relationship, a granular material inlet through which granular material can be passed into the conditioner into an annular gap between the two discs, and a catch container for receiving the granular material which issues from the gap between the two discs by virtue of centrifugal force. According to the invention it is proposed that the catch container has an elastic curtain, wherein the curtain is spaced at least portion-wise from the catch container wall and limits the trajectory of the granular material issuing from the gap.

A grinding chamber of a grinding device for vegetal products suitable to form beverages includes, in its interior, a pair of grinders axially overlapping each other, one of which is rotatable with respect to the other which is kept stationary, a grinder support at least for the rotatable grinder, a motor member connected to the grinder support for setting the rotatable grinder in rotation. The grinding chamber is formed by a first bottom wall, perpendicular to the axis of rotation of the rotatable grinder, adjacent and below the support thereof, and at least a second cylindrical wall, connected axially to the first wall at the peripheral boundary thereof. The grinding chamber also includes a first opening for introducing the product to be ground and with a second opening for discharging the ground product. A labyrinth is provided between the peripheral boundary of the first wall and the grinder support.

A grinding chamber of a grinding device for vegetal products suitable to form beverages includes, in its interior, a pair of grinders axially overlapping each other, one of which is rotatable with respect to the other which is kept stationary, a grinder support at least for the rotatable grinder, a motor member connected to the grinder support for setting the rotatable grinder in rotation. The grinding chamber is formed by a first bottom wall, perpendicular to the axis of rotation of the rotatable grinder, adjacent and below the support thereof, and at least a second cylindrical wall, connected axially to the first wall at the peripheral boundary thereof. The grinding chamber also includes a first opening for introducing the product to be ground and with a second opening for discharging the ground product. A labyrinth is provided between the peripheral boundary of the first wall and the grinder support.

Disclosed is a three-stage millstone including an upper stone having a grain inlet and an inlet path, a middle stone disposed under the upper stone for causing grain, introduced through the inlet path, to move to an edge thereof and grinding the grain using compressive force between the upper and middle stones, a lower stone disposed under the middle stone for secondarily grinding the grain using compressive force between the middle and lower stones, the upper surface of the lower stone being wider than the lower surface of the middle stone and being inclined downward to allow the ground grain to inwardly move from the edge of the middle stone to the center of the lower stone, the lower stone having a grain outlet passage, a rotation device for enabling rotation of the middle stone, other than the upper and lower stones, and an actuator for rotating the middle stone.

A refiner includes a main body, a rotation shaft provided inside the main body, a tapered rotor attached to the rotation shaft with a space therein, a stator provided in the main body, a rotor beating portion provided on the rotor and having a groove between bars and through-holes, a stator beating portion on the stator with a groove between bars and through-holes, a raw material supply portion for supplying a raw material into the main body, and a raw material discharge portion for discharging a beaten raw material outside the main body. A portion of the raw material guided to a small-diameter opening portion of the rotor and the space of the rotor is beaten by passing through the through-holes of the rotor beating portion and the stator beating portion, and is discharged outside the stator beating portion from the through-holes of the stator beating portion.