FORM - 2
THE PATENTS ACT, 1970
(39 OF 1970)
COMPLETE SPECIFICATION
(See Section 10)
TITLE OF INVENTION
"A Distributing Device for Solids"
(a) Thermax Limited (b) having administrative office at D-1, MIDC, Chinchwad, Pune 411 019 India
The following specification particularly describes the nature of the invention and the manner in which it is to be performed.

Field of Invention
The present invention relates to a device for distributing solids in a combustion zone, in particular of a fluid bed combustion system.
Background of the Invention
In firing systems, a device is necessary to feed, introduce and inject solids in combustion zone. Generally, solids are injected pneumatically in combustion zone, in particular of fluid bed combustion systems. It is necessary to effectively distribute and spread the solids. The solid used may be combustible substances, fuel, and sized fuel but not limited to it. The said device is placed in the combustion zone and is subjected to high temperature as well as impingement of pneumatically pressured solid flow on various parts. This results in severe wear of these parts. Maintainability of these devices is of great concern and to reduce down time of the firing system, ease of replacing worn parts is of paramount importance.
US Patent 4,660,768 discloses a nozzle for injecting solids pneumatically. It comprises of a pipe with end that extends into the treatment space surrounded by a hood consisting of a base and a conical wall. The base has vertical deflection surface. The deflecting surface is prone to wear / erosion due to impingement from the pneumatically fed fuel. The invention suffers from the drawback that the base with deflecting surface is attached and not bolted with the conical walls of the hood and the hood is also attached to the pipe. This arrangement leads to replacement of the complete hood in case of wearing out of the deflecting surfaces. Since the hood, base, conical wall and pipe are attached and not bolted, it results in severe restriction on the maintainability of the nozzle. Further, machining the deflecting surface of the shape shown in the invention requires plate of substantial thickness leading to increase in initial cost.
US Patent 4526111 discloses nozzle for fluid bed firing system. It comprises of a pipe for transporting coal/air mixture has an end surrounded by a hood. This pipe extends into the fluid bed, and an axial exit opening is located between the hood
2

and the pipe. The pipe is provided with the axial exit opening, while the hood is spaced from this exit opening. A deflecting face is located in vicinity opposite to the exit opening. A downwardly-pointing baffle is attached underneath a lower edge of the hood to the pipe so as to be adjustable in height.
Thus the study of the related prior art reveals several technological gaps such as:
• Difficult and costly process of replacement of the worn parts, in particular deflecting surfaces where solid impinges; because of permanent attachment of components with each other.
• Substantially increased cost of raw material and in turn manufacturing due to the typical construction of the deflecting surfaces of the nozzles.
• Improper distribution of the solids in reaction zone.
Necessity has constantly been felt to develop a simple, economical, easily replaceable solid-distributing device
The present invention addresses drawbacks of the prior art.
Summary of the Invention
The main object of the present invention is to provide simple, lightweight, economical and easily maintainable device for distributing sized solids in a combustion zone obviating the use of curved shaped deflecting surfaces.
Another object of the invention is to obviate permanent attachment of the deflecting surface with other parts of the device.
Yet another object of the invention is to provide a distribution device for sized fuel in a fluid bed combustion system.
Thus in accordance with the present invention, the device comprises of: A solid fuel distributing device for fluid bed combustion system comprising: a conduit with substantially flat surfaces at the end extending outwards in radial direction to form an inverted bell like structure;
3

a substantially flat plate attached with a member disposed towards outer edge of
the said plate;
wherein the said plate is distanced from the said flat surface of the said conduit to
provide passage for solids;
means for bolting the said flat plate with the said flat surface of the said conduit.
Description of the Invention
Features and advantages of this invention will become apparent in the following detailed description and the preferred embodiments with reference to the accompanying drawings.
Figure 1 Cross section of the solid distributing device (Sheet 1)
The solid fuel distributing device as shown in Figure 1 comprises of a substantially flat lamina / plate that is plate 1 herein after called as flat plate. The flat plate 1 is attached with a member 3 at the periphery. The member 3 acts as a deflecting surface for the fuel. The flat plate 1 is positioned at a distance from the pipe / conduit 2 as shown in the Figure. The pipe 2 has substantially flat surface seen as 4 and 5 in the cross section of the figure extending outwards in radial direction to form inverted bell like structure. The distance between the said flat surfaces 4, 5 and the flat plate 1 provides passage for fuel. The flat plate 1 is bolted with the said flat surfaces of the pipe. As a representation, some of the bolts are shown as 6, 7, 8 in the figure. The bolts may be provided along the periphery of the flat plate 1. The pipe 2 is provided with mounting surface seen as 9 and 10 in the Figure 1.
In one of the embodiment capped bolts are used.
In another embodiment a solid to be distributed is a sized fuel.
In another embodiment, the said member is welded to the flat lamina/plate.
4

In another embodiment the cross section of the said member is cylindrical, oval, flat oval, rectangular, square or combination thereof.
5

We Claim:
1. A solid fuel distributing device for fluid bed combustion system comprising:
a conduit with substantially flat surfaces at the end extending outwards in
radial direction to form an inverted bell like structure;
a substantially flat plate attached with a member disposed towards outer
edge of the said plate;
wherein the said plate is distanced from the said flat surface of the said
conduit to provide passage for solids;
means for bolting the said flat plate with the said flat surface of the said
conduit.
2. A solid fuel distributing device for fluid bed combustion as claimed in claim 1 wherein the said member is welded to the surface of the said flat plate that faces the said conduit.
3. A solid fuel distributing device for fluid bed combustion as claimed in claims 1-2 wherein the said member is of cross section such as cylindrical, oval, flat oval, rectangular, square, profiled or a combination thereof.
4. A solid fuel distributing device for fluid bed combustion system as claimed in claims 1-3 wherein the means for bolting the flat plate with the said flat surface of the pipe is capped bolts.
5. A solid fuel distributing device for fluid bed combustion system as claimed in claims 1-4 wherein the member is made of wear resistant material.
Date: 4/09/2006
Applicant
Thermax Limited
6

Abstract
In firing systems, a device is necessary to feed, introduce and inject solids in
combustion zone. Generally, solids are injected pneumatically in combustion zone, in particular of fluid bed combustion systems. The solid used may be combustible substances, fuel, and sized fuel but not limited to it. The effective distribution and spread of the solids is important. In the conventional devices, because of permanent attachment of components with each other, it is a ddifficult and costly process to replace worn parts, in particular deflecting surfaces where solid impinges with considerable velocity. The present invention provides a simple, economical, easily replaceable solid-distributing device for distributing solids in a combustion zone; in particular of a fluid bed combustion system obviating the use of permanently attached curved shaped deflecting surfaces.