GB2148226A

GB2148226A - Stream splitting and feeding to conveying conduits

Info

Publication number: GB2148226A
Application number: GB08426342A
Authority: GB
Inventors: Alex Francis Wormser; Charles Russell Lowell
Original assignee: WORNSER ENG
Current assignee: WORNSER ENG
Priority date: 1983-10-24
Filing date: 1984-10-18
Publication date: 1985-05-30
Also published as: JPS60114622A; GB8426342D0; JPH0511219Y2; SE8405281D0; JPH02119429U; FR2557269A1; DE3438950A1; AU3441884A; SE8405281L

Abstract

Coal is distributed into a plurality of compartments 26 in a housing 12 which is fed with transport air from a conduit 30 to move the contents of the compartments into conduits 28 extending from the said compartments. The coal is distributed from a rotary duct 20. <IMAGE>

Description

SPECIFICATION Stream splitting This invention relates to burning coal, and more particularly to reliably splitting a larger stream of coal into a plurality of smaller streams.

Background of the invention It has proved difficult in the prior art to satisfactorily divide into smaller streams a larger stream of gas-transported coal. One method has been the socalled aerodynamic stream splitter, in which a pipe carrying the coal divides. This approach, however, has drawbacks: accuracy of division is less than is to be desired; there, are problems of stability; speeds of flow cause erosion; and variant low flow rates in particular conduits may cause settling and plugging. Another, but very expensive, prior art approach has been to use separately fed smaller feed conduits. Finally, in a publication entitled "Some Developments in the Feeding of Coal to Fluidized Bed Combustors", by L. G. Caldwell, it was suggested that coal be distributed by a rotary device among compartments, but then de livered therefrom in a dense condition.

Summary of the invention We have discovered that stream splitting of coal may be done evenly and accurately among the smaller streams with stability and at lower velocities greatly reducing erosion by mechanically evenly dividing the large stream among a plurality of compartments and thereafter moving the contents of the compartments respectively in dilute phase into smaller conduits.

Accordingly, therefore the present invention provides a splitter for dividing coal introduced into a housing into a plurality of streams of equal content which comprises a plurality of compartments in said housing, a plurality of conduits extending from said compartments.

means to evenly distribute material to said compartments, and a transport air conduit for introduction into said housing of conduit air for delivery through said plurality of conduits.

The invention also provides a method of dividing a stream of pieces of coal into a plurality of smaller streams of equal size which comprises introducing said coal into the inlet of a rotor, said rotor having an outlet portion offset from an axis.

rotating said rotor about said axis to move said outlet continuously and consecutively over a plurality of compartments, and moving said coal from said compartments out through conduits for said smaller streams by means of transport air.

In the preferred embodiment distribution to the compartments is by means of a hollow rotor .having an outlet offset from the rotor's axis of rotation.

Preferred embodiment We turn now to a description of the drawing and the structure and operation of a preferred embodiment.

Drawing The drawing is a diagrammatic isometric view of said embodiment.

Structure Referring to the drawing, there is indicated generally at 10 a stream splitter which is said preferred embodiment.

The stream splitter is provided with housing 12 in which is rotatably mounted shaft 14 driven through pulley 16 and belt 18. Mounted on shaft 14 for rotation therewith is hollow conduit rotor 20 carrying on its inlet end funnel 22 and offset so that its lower end 24 is not coaxial with shaft 14 but rather is disposed to during rotation sweep the lower annulus divided into compartments by walls 26. From each compartment defined by a pair of walls 26 extends an outlet pipe 28.

Conduits 28 at 121 to 2 inches (38-51 mm) in diameter and inlet conduit 30 is of size to provide air in amount sufficient to maintain desired velocities in the pipes 28.

Operation In operation, sufficient transport air is injected through conduit 30 to maintain outlet air velocity in conduits 28 at 40 feet per second (12.2 m/sec).

This amount of air and air velocity is sufficient to transport the coal through conduits 28 in a dilute (i.e., airborne) form, in contradistinction to the dense or non-airborne form in which delivery from the splitter occurred in the Caldwell publication above referred to. Coal is provided from a crusher through funnel 22 in inch (6.35 mm) pieces.

As rotor 20 rotates, it continuously consecutively deposites equal amounts of coal in the various compartments defined by walls 26. From these compartments the transport air from conduit 30, moving through housing 12, moves equal amounts of coal through pipes 28.

1. A splitter for dividing coal introduced into a housing into a plurality of streams of equal content which comprises a plurality of compartments in said housing, a plurality of conduits extending from said compartments, means to evenly distribute material to said compartments, and.

a transport air conduit for introduction into said housing of conduit air for delivery through said plurality of conduits.

2. The splitter of claim 1 in which said means to evenly distribute material is a rotatably mounted hollow conduit, said conduit having an outlet portion offset from from the axis of rotation of said rotor and disposed over a zone occupied by said compartments.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Stream splitting This invention relates to burning coal, and more particularly to reliably splitting a larger stream of coal into a plurality of smaller streams. Background of the invention It has proved difficult in the prior art to satisfactorily divide into smaller streams a larger stream of gas-transported coal. One method has been the socalled aerodynamic stream splitter, in which a pipe carrying the coal divides. This approach, however, has drawbacks: accuracy of division is less than is to be desired; there, are problems of stability; speeds of flow cause erosion; and variant low flow rates in particular conduits may cause settling and plugging. Another, but very expensive, prior art approach has been to use separately fed smaller feed conduits. Finally, in a publication entitled "Some Developments in the Feeding of Coal to Fluidized Bed Combustors", by L. G. Caldwell, it was suggested that coal be distributed by a rotary device among compartments, but then de livered therefrom in a dense condition. Summary of the invention We have discovered that stream splitting of coal may be done evenly and accurately among the smaller streams with stability and at lower velocities greatly reducing erosion by mechanically evenly dividing the large stream among a plurality of compartments and thereafter moving the contents of the compartments respectively in dilute phase into smaller conduits. Accordingly, therefore the present invention provides a splitter for dividing coal introduced into a housing into a plurality of streams of equal content which comprises a plurality of compartments in said housing, a plurality of conduits extending from said compartments. means to evenly distribute material to said compartments, and a transport air conduit for introduction into said housing of conduit air for delivery through said plurality of conduits. The invention also provides a method of dividing a stream of pieces of coal into a plurality of smaller streams of equal size which comprises introducing said coal into the inlet of a rotor, said rotor having an outlet portion offset from an axis. rotating said rotor about said axis to move said outlet continuously and consecutively over a plurality of compartments, and moving said coal from said compartments out through conduits for said smaller streams by means of transport air. In the preferred embodiment distribution to the compartments is by means of a hollow rotor .having an outlet offset from the rotor's axis of rotation. Preferred embodiment We turn now to a description of the drawing and the structure and operation of a preferred embodiment. Drawing The drawing is a diagrammatic isometric view of said embodiment. Structure Referring to the drawing, there is indicated generally at 10 a stream splitter which is said preferred embodiment. The stream splitter is provided with housing 12 in which is rotatably mounted shaft 14 driven through pulley 16 and belt 18. Mounted on shaft 14 for rotation therewith is hollow conduit rotor 20 carrying on its inlet end funnel 22 and offset so that its lower end 24 is not coaxial with shaft 14 but rather is disposed to during rotation sweep the lower annulus divided into compartments by walls 26. From each compartment defined by a pair of walls 26 extends an outlet pipe 28. Conduits 28 at 121 to 2 inches (38-51 mm) in diameter and inlet conduit 30 is of size to provide air in amount sufficient to maintain desired velocities in the pipes 28. Operation In operation, sufficient transport air is injected through conduit 30 to maintain outlet air velocity in conduits 28 at 40 feet per second (12.2 m/sec). This amount of air and air velocity is sufficient to transport the coal through conduits 28 in a dilute (i.e., airborne) form, in contradistinction to the dense or non-airborne form in which delivery from the splitter occurred in the Caldwell publication above referred to. Coal is provided from a crusher through funnel 22 in inch (6.35 mm) pieces. As rotor 20 rotates, it continuously consecutively deposites equal amounts of coal in the various compartments defined by walls 26. From these compartments the transport air from conduit 30, moving through housing 12, moves equal amounts of coal through pipes 28. CLAIMS

3. The method of dividing a stream of pieces of coal into a plurality of smaller streams of equal size which comprises introducing said coal into the inlet of a rotor, said rotor having an outlet portion offset from an axis, rotating said rotor about said axis to move said outlet continuously and consecutively over a plurality of compartments, and moving said coal from said compartments out through conduits for said smaller streams by means of transport air.

4. A splitter for dividing coal introduced into a housing into a plurality of streams substantially as described with reference to the drawing.