Abstract: A method for comminuting heat-sensitive feedstock, particularly thermoplastics, rubber, caoutchouc, and elastomers, to a particle size of less than 500 ?m, preferably less than 425 ?m. Process steps are provided to achieve an economic material processing without the use of cryogenic comminution. First, a precomminution of the feedstock to a size smaller than 4 mm is performed in a rotating comminuting device through which a first process gas PG1 flows. Then, a fine grinding is performed of the precomminuted feedstock to a size smaller than 500 ?m, preferably smaller than 425 ?m, in a rotating fine grinding device through which a second process gas PG2 flows. Whereby the temperature of the precomminuted feedstock in the outlet of the fine grinding is regulated in a second control circuit by adding water to the precomminuted feedstock before and/or during and/or after the fine grinding.

Abstract: To avoid sandwiching of a sucked object in a gap between an inner wall of a fan case and a fan of a hand-held suction apparatus, an entering regulation part is positioned to extend into the air intake opening to return sucked objects back into the air intake opening and prevent sandwiching in the gap.

Abstract: An apparatus and process for naturally recycling poultry carcasses for use as a nutritional supplement, the apparatus generally consists of four modules: an enzymatic digest medium mixing assembly that self adjusts for pH; a mobile grinding assembly mounted on a truck trailer; a digesting and emulsifying assembly which includes a heated tank and separator; and a drying system. Carcasses are loaded into the grinder, and the ground carcasses are pumped into a storage tank with the enzymatic digest medium to produce a protein soluble mixture. The particle size of this mixture is then further reduced, and transported to a centralized and stationary processing plant for digesting and emulsifying. The remaining emulsified proteins are then dried. The resulting pellet-like pieces are uniformly sized for packaging.

Abstract: A method of controlling the operation of the bowl mills in a coal-fired steam generating power plant is disclosed; and in particular a method of controlling the operation of such bowl mills such that the furnace of a steam generating power plant can more rapidly respond to abrupt changes in the demands placed upon the output of the furnace due to abrupt changes in the power requirements of an electric power grid.

Abstract: Apparatus for reducing the particle size of material subjected to the impact of the hammers of a material reducing hammer mill in which oversize material impacted by the mill hammer is prevented from getting into the stream of properly sized material by being thrown against a flow impeding member which makes such material difficult to pass a material sizing fan having spinner blades that can not effectively intercept particles that are hard, improperly reduced, and require reduction. Material flow impeding angular passages which offer resistance to flow of material that is hard and/or oversized are located to intercept the oversized material and return such material to the material reducing hammer mill for further size reduction before it is able to get into the product stream.

Abstract: A material reducing mill having a construction which operates to create a circulation of material in the mill to effect a thorough reduction of material added to the material undergoing reduction. The mill is further constructed with a rotary device which is associated with an external collection system, which device constantly samples the circulation in the mill so as to withdraw that portion which can be fed into the collection system. Furthermore, the external collection system is provided with sensors which are adapted to regulate the circulation of the material intended to be reduced to micron size portions.

Abstract: An improved vertical grinding mill is provided which has a shell, a vertical helically bladed shaft rotatably mounted in the shell, a collector, a drive for the shaft, and a fan or a pump. The shaft is hollow and its lower end is open at the bottom of the shell. This assures a uniform distribution of the material to be treated, the grinding medium and the product particles and thus high production efficiency.

Abstract: A particle classifier apparatus and method for separating coarse particles from a mixture of particles carried in a gas stream, for preferred use in combination with a coal crushing mill. In the classifier, the gas-solids stream is passed through a plurality of internal upper angled fixed vanes for imparting a rotational motion to the particles. The rotating gas-solids stream then flows downwardly past 3-6 pivotable deflector vanes located entirely within the rotating gas-solids stream for effectively separating the larger size particles in the gas stream from the smaller particles. The smaller particles are then carried upwardly by the gas stream, such as coal particles carried by an air stream into a combustion zone of a boiler, while the larger size particles are returned downwardly, such as to a crusher for further size reduction and for recycling the particles through the classifier.

Abstract: A pulverizing bowl mill embodying improved air deflector means and particularly suited for use in effecting the grinding of material. The subject bowl mill includes a substantially closed separator body in which a grinding table is supported for rotation. A plurality of grinding rolls are supported within the separator body and cooperate with the rotating grinding table to effect the grinding of the material, which is disposed upon the grinding table. Air deflector means corresponding in number to the number of grinding rolls are mounted within the separator body so as to be located in juxtaposed relation to the inner surface of the separator body and so that an air deflector means is interposed between each pair of adjacent grinding rolls. An air supply means suitably formed in the separator body is associated with each of the air deflector means. Each of the air supply means is operable to supply air from an external source thereof therethrough to the interior of the separator body.