초록 ▼

Substance particulate in the general size range of minus 30 Mesh U.S. Standard to about 1 micron is separated into portions based on the densities of those components making up the total by drying to about 1% moisture and air conveying the substance through a duct in which the material assumes a str

Substance particulate in the general size range of minus 30 Mesh U.S. Standard to about 1 micron is separated into portions based on the densities of those components making up the total by drying to about 1% moisture and air conveying the substance through a duct in which the material assumes a stratified arrangement dictated by particle density. Means are provided by air duct configuration and partial flow diversion to remove appropriate laminar segments of the air-solids mixture. Light, medium and heavy ash and pyritic Sulfur in substantial percentages can be removed from bituminous coal fines embodying this principle in a negative air atmosphere. After beneficiation of bituminous coal fines any undesired pyritic or organic Sulfur can be contained by intimately mixing calcium hydroxide with the coal in the amount of 2.24 parts of calcium hydroxide to one (1) part of Sulfur by weight. Approximately 4½% ash by weight will be generated for each 1% elemental Sulphur contained from the fine coal particulate upon heating and combustion.

대표청구항 ▼

A method for separating heavy weight, middle weight and light weight solid particles from an admixture of solid particulate substances containing same which comprises (i) heating and drawing a conveying gas through a closed separation system comprising a series of three separation stages all in comm

A method for separating heavy weight, middle weight and light weight solid particles from an admixture of solid particulate substances containing same which comprises (i) heating and drawing a conveying gas through a closed separation system comprising a series of three separation stages all in communication with each other; (ii) prior to said first separation stage, contacting said heated conveying gas with said admixture with solid particulate substances having a mesh size of minus 30 to minus 250 and introducing said conveying gas and admixture of solid particulate substances into an elongated vertical heating duct having a curved section at the upper end so as to remove surface moisture from said particulate substances; (iii) drawing said heated conveying gas with said dried admixture of particles through the curved section of said elongated heating duct at a flow rate and a solids to heated conveying gas loading that produces a laminar flow wherein heavy weight particles are positioned as a lamina in a different segment of the duct than the remaining middle weight and light weight particles by centripetal force induced therein; (iv) drawing the laminar flow of particles through said first separation stage where the dried particles are passed through a first elbow-shaped duct; (v) splitting away said heavy particle lamina from said remaining middle and light weight particle laminae by a first adjustable splitting means comprising a movable deflector positioned within said elbow-shaped duct; (vi) drawing additional air into said first elbow-shaped duct via an adjustable air inlet means located ahead of said splitting means for controlling the degree of centripetal force generated at the first separation stage; (vii) drawing the remaining middle and light weight particles to said second separation stage where the particles are passed through a second elbow-shaped duct to produce a laminar flow wherein middle weight particles are to be separated from the remaining particles positioned as laminae in different segments of the duct by centripetal force induced therein; (viii) splitting away some of said middle weight particles as a lamina by a second adjustable splitting means comprising a movable deflector positioned within said second duct; (xi) drawing the remaining middle and light weight particles into a circular duct wherein a centripetal force is induced to create a lamina of middle weight particles not separated in step (vii); (x) splitting away more of the middle weight particles in the lamina created in step (ix) by a third adjustable splitting means comprising a movable deflector position within said circular duct; and (xi) drawing the remaining particles to said third separation stage comprising a cyclone separator wherein light weight particles are separated as a cyclone overflow from remaining middle weight particles separated as a cyclone underflow.