Claims
- 1. An unfired drying and sorting apparatus for preparation of solid fuel prior to firing in a combustion furnace incorporating:
- a supply of sized moisture bearing solid fuel and inert material to be dried and sorted;
- a vertical chamber;
- a fluidized bed comprising a mixture of said sized particles of said solid fuel and inert material;
- means for continuously adding a stream of said sized particles to said bed for drying and sorting;
- a sorter at the base of said vertical chamber having a floor for supporting said fluidized bed within said vertical chamber;
- ports in said floor;
- means continuously furnishing unsaturated air/gas to said ports;
- said ports adapted to discharge said unsaturated air/gas into said bed directionally and in a distributed pattern over said sorter floor fluidizing said mixture of sized particles of solid fuel and inert material and driving said mixture in a retraceable path around said floor of said bed, said unsaturated air/gas upflow through said bed vaporizing moisture borne by said particles and transporting said vapor in said air/gas stream exiting from said bed;
- means for removal of said inert particles from said bed through a first collection point including a trough-like depression in said bed floor wherein means are provided for directing a portion of said directional fluidizing air toward said first collection point at the bottom of said trough and adapted for transporting a heavier/more dense non-combustible portion of said solid material through said trough in a direction transverse to the general direction of particle flotation above said trough and toward said first collection point;
- said trough-like depression being located downstream of the point where said moisture bearing sized solid particles are introduced to said bed;
- means for segregating said solids directed to said first collection point adapted to pass said heavier/more dense solid materials through said first collection point and to reject lighter/less dense fuel portions of said particles to said bed upper portion;
- a second collection point at said upper portion of said bed adapted for removing said lighter/less dense combustible portion of said solid material from said vertical chamber;
- said means for adding a continuous supply of said sized particles to said bed and said first and second collection points being located with reference to said retraceable path in a manner to provide retention time for said particles in said bed and to cause particles from said point of entry to said bed in a fluidized state to flow to said second or third collection points selectively by virtue of particle density and over a period of time to facilitate sorting;
- means located at the outlet of said vertical chamber for removal of air/gas and water vapor;
- means connected to said outlet means adapted to separate solid particles entrained in said air/gas and water vapor stream; means for measurement of differential pressures across said bed at various elevations and adapted to determine bed height; and
- means for injecting secondary air horizontally at the top elevation of said bed at varying elevations and adapted for selectively skimming fine solids from said top of said bed, entraining said fines in said outlet air/gas stream.
- 2. An apparatus as defined in claim 1 and including:
- means for measuring differential pressure across said bed for a given bed depth and adapted for adjustment of removal rate of said heavier/more dense solid material through said first collection point, an increase in differential pressure requiring an increase in removal rate and vice-versa.
- 3. An apparatus as defined in claim 1 and including;
- means for raising or lowering said bed overflow level in response to quality of material to be processed, raising level to accomodate lower density solid materials processed and vice-versa.
- 4. An apparatus as defined in claim 1 and including:
- a means for collecting and sorting said solid particles withdrawn from any of said first or second collection points; and
- means for recycling said stored withdrawn solid particles as a batch to said bed as a continuous supply of solid particles to said bed for classification of said solids by density through said first and said second collection points.
Parent Case Info
This invention is a continuation-in-part of U.S. patent application Ser. No. 06/464,062 filed 02/03/83 now U.S. Pat. No. 4,449,483 and is a variation thereupon.
US Referenced Citations (9)
Continuation in Parts (1)
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Number |
Date |
Country |
Parent |
464062 |
Feb 1983 |
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