Abstract: A compressive grinder for a bed of materials, includes: a cylinder having a horizontal axis, and an inner wall having a raceway for a grinding roller arranged inside the cylinder; elements for rotating the cylinder about the axis; the grinding roller having an axis parallel to that of the cylinder; elements for urging the grinding roller against the raceway; an input for supplying material to be ground at one end of the cylinder and an outlet for ground material at the other end. The grinder includes: a smoothing roller upstream of the grinding roller in the cylinder's direction of rotation; elements for keeping the smoothing roller adjacent to and separated from the raceway, such that, upon each cylinder turn, the material consecutively passes under the smoothing roller and then under the grinding roller, the smoothing roller exerting, on the bed of materials, a pressure that smoothes the surface thereof.

Abstract: A fibrous panel is molded in two or more progressively formed mold members each comprising a porous support plate to which a plurality of rigid mold pieces are affixed. The mold pieces are truncated 3D tapered structures, and are arranged on the support plate in a regular array so that an intersecting grid or lattice of channels is defined between them. A fiber stock is poured into a first mold member and the stock is compressed and dewatered to form a panel. The panel is removed from the first mold member and placed into a second mold member having narrower and shallower channels whose side walls are more upright than those of the first mold member. The panel is further compressed and dewatered in the second mold member, and is densified in both the vertical and lateral directions by virtue of the progressive formation of the mold members.