FORM -2
THE PATENTS ACT, 1970
(39 of 1970)
&
THE PATENTS RULES, 2003
COMPLETE
Specification
(See Section 10; rule 13)
DISTRIBUTION ARRANGEMENT FOR A FLUIDIZED BED COMBUSTION/GASIFICATION SYSTEM
THERMAX LIMITED
an Indian Company
of D-13, MIDC Industrial Area, R.D. Aga Road,
Chinchwad, Pune - 411 019,
Maharashtra, India.
NAME OF THE INVENTORS
1. SINGH GHANSHYAM
2. MARATHE ASMITA MAYURESH
3. GUPTA DEVKUMAR
4. MITRA CHAITANYA B.
The following specification particularly describes the invention and the manner in which it is to be performed.

FIELD OF THE DISCLOSURE
The present disclosure generally relates to an air/ O2 and steam distribution arrangement for a fluidized bed combustion / gasification system.
BACKGROUND
Typically, a fluidized bed combustion / gasification system includes a distribution plate having provision for supplying air/02, steam and fuel. A fluidized bed combustion / gasification system is connected to an opening for ash removal. However, the conventional fluidized bed combustion / gasification system suffers from various limitations, such as:
• problems of falling solids in a wind box;
0 solids removed with contained heat;
• non-uniform distribution of air/02, steam and fuel; and
• ineffective fluidization and ash removal.
Accordingly, there is need of a distribution arrangement that facilitates efficient ash removal and heat recovery.
OBJECTS
Some of the objects of the system of the present disclosure, which at least one embodiment herein satisfies, are as follows:

It is an object of the system of the present disclosure to ameliorate one or more problems of the prior art or to at least provide a useful alternative,
An object of the system of the present disclosure is to provide a distribution arrangement that facilitates better distribution of air/oxygen and steam, thereby enhancing performance of a gasification system.
Another object of the system of the present disclosure is to provide a distribution arrangement that facilitates efficient ash removal.
Yet another object of the system of the present disclosure is to provide a distribution arrangement that recovers heat from ash efficiently.
Additionally, an object of the system of the present disclosure is to provide a distribution arrangement that prevents clinkering.
Furthermore, an object of the system of the present disclosure is to provide a distribution arrangement that improves residence time of solid fuel particles inside a gasification system.
Moreover, an object of the system of the present disclosure is to provide a distribution arrangement that comparatively improves gasification process and improves productivity.

Also, an object of the system of the present disclosure is to provide a distribution arrangement that reduces cost of manufacturing and operation.
Furthermore, an object of the system of the present disclosure is to provide a distribution arrangement that is comparatively more efficient.
Other objects and advantages of the system of the present disclosure will be more apparent from the following description when read in conjunction with the accompanying figures which are not intended to limit the scope of the present disclosure.
SUMMARY
In accordance with one aspect of the present disclosure, a distribution arrangement for a gasification system is disclosed. The distribution arrangement includes a distribution plate, an air/02 and steam distribution plenum and a hopper assembly. The distribution plate supports the combustible material thereon. The air/ O2 and steam distribution plenum is disposed inside a combustion/ gasification chamber. The air/ O2 and steam distribution plenum has a plurality of through vertical passages for ash removal. The hopper assembly is disposed below the air/ O2 and steam distribution plenum and adapted to recover heat from the ash moving down through the hopper assembly.
Typically, the vertical passages are functionally connected to a fluidized bed and the hopper assembly.

The vertical passages are of predetermined geometrical shape.
Typically, the vertical passages are arranged in radial configuration on the plenum.
Alternatively, the vertical passages may be arranged on a circumferential portion of the plenum.
In one embodiment, each of the plurality of through vertical passages has a downward divergent configuration for facilitating smooth flow of ash.
Alternatively, in another embodiment the distribution arrangement is adapted to facilitate utilization of the heat recovered from the ash for preheating the air/ O2 and steam entering into the combustion/ gasification chamber.
In one embodiment, the hopper assembly further includes a fluid jacket for facilitating heating of fluid flowing there through by recovering heat from the ash moving down through the hopper assembly.
Typically, a plurality of nozzles is functionally connected to the air/ 02 and steam distribution plenum for facilitating uniform mixing of air/ 02, steam and fuel.
Typically, the distributor plate is having an inclined configuration.

Specifically, the distributor plate is inclined towards the passage for ash removal for facilitating smooth flow of ash to the passage for ash removal.
Alternatively, the distributor plate has a conical configuration.
Particularly, the distributor plate is provided with tangential apertures configured thereon and the passage for ash removal is centrally disposed on the distributor plate.
In accordance with another embodiment, the distributor plate has an inverted cone configuration
Typically, with the passages for ash removal are disposed circumferentially around the distributor plater
BRIEF DESCRIPTION OF ACCOMPANYING DRAWINGS
The disclosure will now be explained in relation to the non-limiting accompanying drawings, in which:
Figure 1 illustrates a top view of a distribution arrangement for a gasification system in accordance with one embodiment of the present disclosure;
Figure 2 illustrates a sectional view of the distribution arrangement of Figure 1 along a sectional line X-X;

Figure 3a illustrates a side view of a fluidized bed gasifier having a tapered/ inclined distributor plate and an ash pipe in accordance with an embodiment of the present disclosure;
Figure 3b illustrates a top view of the distributor plate shown in fluidized bed gasifier of Figure 3a;
Figure 4a illustrates a fluidized bed gasifier having a conical distribution plate in accordance with an embodiment of the present disclosure;
Figure 4b illustrates the conical distribution plate of the fluidized bed gasifier of Figure 4a;
Figure 4c illustrates an enlarged view of a section "H" of the conical distribution plate of Figure 4b configured with tangential apertures in accordance with an embodiment of the present disclosure;
Figure 5a illustrates a fluidized bed gasifier having an inverted cone type distributor plate in accordance with an embodiment of the present disclosure; and
Figure 5b illustrates a close up view of the ash discharge slits of the fluidized bed gasifier of Figure 5a.

DETAILED DESCRIPTION
The present disclosure will now be described with reference to the accompanying drawings which do not limit the scope and ambit of the disclosure. The description provided is purely by way of example and illustration.
The embodiments herein and the various features and advantageous details thereof are explained with reference to the non-limiting embodiments in the following description. Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the embodiments herein. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly, the examples should not be construed as limiting the scope of the embodiments herein.
The description hereinafter, of the specific embodiments will so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of

preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the embodiments as described herein.
Referring to Figures 1 and 2, a distribution arrangement 100 is disclosed for a gasification system. The distribution arrangement 100 includes an air/ O2 and steam distribution plenum 102 and a hopper assembly 104.
The air/ O2 and steam distribution plenum 102 is disposed inside a combustion/ gasification chamber 106. The air/ O2 and steam distribution plenum 102 has a plurality of through vertical passages 108 for ash removal. The vertical passages 108 are functionally connected to a fluidized bed (not shown) and the hopper assembly 104. Further, the vertical passages 108 can be configured of various predetermined geometrical shapes. In one embodiment, the vertical passages 108 are arranged in radial configuration on the plenum 102. Alternatively, in another embodiment, the vertical passages 108 can be arranged on circumferential portion of the plenum 102 (not shown). However, the present invention is not limited to any particular arrangement of the vertical passages 108 on the plenum 102. In one embodiment, each of the plurality of through vertical passages 108 has a downward divergent configuration for facilitating smooth flow of ash.
The hopper assembly 104 is disposed below the air/ 02 and steam distribution plenum 102 and adapted to recover heat from the ash moving down through the hopper assembly 104 after combustion. The hopper assembly 104 further includes a fluid jacket 110 for cooling the ash by the

heat recovery from ash moving down through the hopper assembly 104. The fluid jacket 110 includes a fluid inlet 114 for facilitating entry of fluid. Also, the fluid jacket 110 includes a fluid outlet 116 for facilitating exit of heated fluid by recovering heat from the ash, out of the fluid jacket 110. Exit of the ash from the hopper assembly 104 is represented by a reference numeral "120".
Also, the heat recovered from the ash is utilized for pre-heating the air/ O2 and steam entering into the combustion/ gasification chamber 106. Inlet of the air/ O2 and steam is represented by a reference numeral "118" in Figure 2. In one embodiment, the heat recovered from the ash is utilized for preheating the air/ O2 and steam entering into the combustion/ gasification chamber 106 by passing over the air/ O2 and steam through a jacket of the hopper assembly 104. However, the present invention is not limited to any particular devices and methods used for pre-heating the air/ O2 and steam.
Further, the distribution arrangement 100 includes a plurality of nozzles/ bubble caps 112 functionally connected to the air/ 02 and steam distribution plenum 102 for facilitating uniform mixing of air/ 02, steam and fuel. In one embodiment, for very small diameter (100-250mm) of a fluidized bed, the bubble caps/ nozzles 112 are few, so the ash can flow through an annular gap provided at the periphery of the fluidized bed.
The fluidized bed gasifier may further include a distributor plate. The distributor plate of the fluidized bed gasifier may have different configurations. For example, Figure 3a illustrates a side view of a fluidized

bed gasifier 200 having a tapered/inclined distributor plate 202 and an ash pipe 204 in accordance with an embodiment of the present disclosure. The fluidized bed gasifier 200 includes a plurality of bubble caps 206 disposed over the distributor plate 202. The coal enters the fluidized bed gasifier 200 along the line represented by "C", the air / 02 and steam enters the gasifier along the line represented by "A+S". The ash is removed from the gasifier via the ash pipe 204. More specifically, the coal enters the fluidized bed gasifier 200 along the line represented by "C" so as to dispense coal above the tapered/inclined distributor plate 202. The air / 02 and steam enters the gasifier along the line represented by "A+S" to provide air / 02 and steam to underside of the tapereoVinclined distributor plate 202.
The fluidized bed gasifier 200 with tapered/inclined distributor plate 202 is useful when the column is operated near the softening temperature of the coal and there is tendency of formation of good amount of clinker. The arrangement of fluidized bed gasifier 200 with tapered/inclined distributor plate 202 as illustrated in Figure 3a and Figure 3b facilitates in rolling down of the clinkers formed on the tapered/inclined distributor plate 202 down to the ash pipe 204 located at the other end of the taper/ inclination. The orifice are designed such that the same pressure is felt by each bubble cap 206 by adjusting the hole size and the cross-sectional area.
Figure 4a illustrates a fluidized bed gasifier 300 having a conical distribution plate 302 in accordance with an embodiment of the present disclosure. Figure 4b illustrates the conical distribution plate 302 of the fluidized bed gasifier 300. The coal enters the fluidized bed gasifier 300

along the line represented by "CI", the air / 02 and steam enters the gasifier 300 along the line represented by "Al+Sl". The ash is removed from the gasifier 300 via the ash pipe 304 that is centrally located inside the gasifier 300. Figure 4c illustrates an enlarged view of a section "H" of the conical distribution plate 302 of the fluidized bed gasifier 300 that is configured with tangential apertures 306 in accordance with an embodiment of the present disclosure. More specifically, the coal enters the fluidized bed gasifier 300 along the line represented by "CI" so as to dispense coal above the conical distribution plate 302. The air / 02 and steam enters the gasifier along the line represented by "Al+Sl" to provide air / 02 and steam to underside of the conical distribution plate 302.
This conical distributor plate 302 for fluidized bed gasifier 300 as illustrated in Figure 4a, 4b and 4c is provided with provision for tangential entry of the air /02 mixture. Such a configuration of the fluidized bed gasifier 300 assists in creating swirling motion on the surface of the distributor plate 302 which provides better mixing and contact between the solids and gas. The central opening/ ash pipe 304 is for ash removal that also helps collecting the heavy /clinker particles in the ash pipe.
Figure 5a illustrates a fluidized bed gasifier 400 having an inverted cone type distributor plate 402. The fluidized bed gasifier 400 is further provided with ash discharge slits 404 for facilitating removal of the ash. The fluidized bed gasifier 400 further includes a plurality of bubble caps 406 disposed over the distributor plate 402. The coal enters the fluidized bed gasifier 400 along the line represented by "C2", the air / 02 and steam enters the gasifier

400 along the line represented by "A2+S2". The ash is removed from the gasifier 400 via the ash discharge slits 404 that are disposed around the inverted cone type distributor plate 402. More specifically, the coal enters the fluidized bed gasifier 400 along the line represented by "C2" so as to dispense coal above the conical distribution plate 402. The air / 02 and steam enters the gasifier along the line represented by "A2+S2" to provide air / 02 and steam to underside of the conical distribution plate 402.
The inverted cone type distributor plate 402 as illustrated in Figure 5a is having a configuration that facilitates in easy mobility of the heavy or clinker particles to the ash discharge points i.e. the ash discharge slits 404 and hence aids in continuous operation of the gasifier 400. In accordance with an embodiment, the ash discharge slits 404 are disposed at the periphery of the gasifier 400 for collecting the heavy particles.
TECHNICAL ADVANCEMENTS AND ECONOMICAL SIGNIFICANCE
The technical advancements offered by the system of the present disclosure which add to the economic significance of the disclosure include the realization of:
• a distribution arrangement that facilitates better distribution of air/oxygen and steam, thereby enhancing performance of a gasification system;
• a distribution arrangement that facilitates ash removal;

• a distribution arrangement that prevents clinkering;
• a distribution arrangement that improves residence time of solid fuel particles inside a gasification system;
• a distribution arrangement that comparatively improves gasification process and improves productivity;
• a distribution arrangement that reduces cost of manufacturing and operation; and
• a distribution arrangement that is efficient.
Throughout this specification the word "comprise", or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated element, integer or step, or group of elements, integers or steps, but not the exclusion of any other element, integer or step, or group of elements, integers or steps.
The use of the expression "at least" or "at least one" suggests the use of one or more elements or ingredients or quantities, as the use may be in the embodiment to achieve one or more of the desired objects or results. Any discussion of documents, acts, materials, devices, articles or the like that has been included in this specification is solely for the purpose of providing a context for the disclosure. It is not to be taken as an admission that any or all of

these matters form part of the prior art base or were common general knowledge in the field relevant to the disclosure as it existed anywhere before the priority date of this application.
The numerical values mentioned for the various physical parameters, dimensions or quantities are only approximations and it is envisaged that the values higher/lower than the numerical values assigned to the parameters, dimensions or quantities fall within the scope of the disclosure, unless there is a statement in the specification specific to the contrary.

We claim:
1. A distribution arrangement for a gasification system, said distribution
arrangement comprising:
• a distribution plate for supporting combustible material thereon;
• an air/ 02 and steam distribution plenum disposed inside a
combustion/ gasification chamber, said air/ O2 and steam distribution
plenum having a plurality of through vertical passages for ash
removal; and
• a hopper assembly disposed below said air/ 02 and steam distribution
plenum and adapted to recover heat from said ash moving down
through said hopper assembly.
2. The distribution arrangement as claimed in claim 1, wherein said vertical passages are functionally connected to a fluidized bed and said hopper assembly.
3. The distribution arrangement as claimed in claim 1, wherein said vertical passages are of predetermined geometrical shape.
4. The distribution arrangement as claimed in claim 1, wherein said vertical passages are arranged in radial configuration on said plenum.
5. The distribution arrangement as claimed in claim 1, wherein said vertical passages are arranged on a circumferential portion of said plenum.
6. The distribution arrangement as claimed in claim 1, wherein each of said plurality of through vertical passages has a downward divergent configuration for facilitating smooth flow of ash.

7. The distribution arrangement as claimed in claim 1, wherein said hopper
assembly further comprises a fluid jacket for cooling the ash by recovering
heat from ash moving down through the hopper assembly.
8. The distribution arrangement as claimed in claim 1, wherein said fluid
jacket is adapted to facilitate utilization of the heat recovered from said ash
for pre-heating said air/ 02 and steam entering into said combustion/
gasification chamber.
9. The distribution arrangement as claimed in claim 1, further comprising a
plurality of nozzles functionally connected to said air/ 02 and steam
distribution plenum for facilitating uniform mixing of air/ 02, steam and
fuel.
10.The distribution arrangement as claimed in claim 1, wherein said distributor plate has an inclined configuration.
11. The distribution arrangement as claimed in claim 1, wherein said
distributor plate is inclined towards said passage for ash removal for
facilitating smooth flow of ash to said passage for ash removal.
12. The distribution arrangement as claimed in claim 1, wherein said
distributor plate has a conical configuration.
13. The distribution arrangement as claimed in claim 1, wherein said
distributor plate is provided with tangential apertures configured thereon
and said passage for ash removal is centrally disposed on said distributor
plate.

14. The distribution arrangement as claimed in claim 1, wherein said distributor plate has an inverted cone configuration.
15.The distribution arrangement as claimed in claim 1, wherein said passages for ash removal are disposed circumferentially around said distributor plate.