Description:FORM 2
THE PATENT ACT 1970
(39 OF 1970)
&
The Patent Rules, 2003
COMPLETE SPECIFICATION
(See Section 10 and Rule 13)

1 TITLE OF THE INVENTION :
IMPROVED ROOF-MOUNTED BURNER MODULE WITH REFRACTORY BLOCKS FOR SINTER MACHINE IGNITION FURNACE.



2 APPLICANT (S)

Name : STEEL AUTHORITY OF INDIA LIMITED;

Nationality : A Govt. of India Enterprise;

Address : Research & Development Centre for Iron & Steel, Doranda, Ranchi, Jharkhand, India,PIN-834002.




3 PREAMBLE TO THE DESCRIPTION

COMPLETE

The following specification particularly describes the invention and the manner in which it is to be performed.

FIELD OF THE INVENTION
The present invention relates to a roof mounted burner module fitted with precast and pre-fired refractory block for sinter machine ignition furnace involving improvement in design of existing curtain flame burner module along with its refractory burner block installed in the ignition furnace for combusting the top layer of sinter bed in order to enhance the life of existing curtain flame burner module.

BACKGROUND OF THE INVENTION

The sinter machine is provided with an ignition furnace for combusting the top layer of sinter bed. The existing curtain flame / multi slit burner modules (Fig. 1) are installed in the roof of sinter machine. The curtain flame / multi slit burner module consists of a number of small capacity burners mounted on the roof of a low height furnace in a single row across the sinter bed, with small gaps in-between. Each burner module consists of multiple burners depending upon the width of sinter machine. The existing curtain flame / multi slit burner module is provided with a refractory burner block made of low moisture castables and Y-shaped metallic anchors located at suitable distances (Fig.2 & Fig.3). The life of existing curtain flame / multi slit burner modules is about 6 months leading to requirement of furnace shutdown for repair/replacing the burner modules.
The various parts shown in above figures 2 – 3 are as follows:
Part 1 and Part 2: Burner outer enclosure plates,
Part 3: Y- shaped metallic anchors,
Part 4: Primary combustion air entry pipe,
Part 5: Secondary combustion air entry openings,
Part 6: Refractory burner block.

However, the tips of the curtain flame burners protected by refractory casting are more prone to failure due to crack generation and thermal spalling. The burner modules are changed / repaired after every 6 months (approx). The replacement of burner modules needs 3 - 4 days shut down time leading to sinter production loss.

OBJECTS OF THE INVENTION
The basic object of the present invention is directed towards a roof mountable burner module for sinter machine ignition furnace favouring enhancing the life of existing curtain flame burner module thereby reducing downtime of furnace resulting enhance sinter production.

SUMMARY OF THE INVENTION

The basic aspect of the present invention is directed to a roof mountable burner module adapted for enhanced life requiring less downtime comprising :

metallic burner modules providing for burners for firing of gaseous fuels ;

said metallic burner module having metallic enclosure including gaseous fuel inlet pipes , primary combustion air entry openings and secondary combustion air entry openings;

said metallic burner module securely supporting precast and pre-fired refractory block suitable for ignition furnace.

A further aspect of the present invention is directed to said roof mountable burner module adapted for enhanced life requiring less downtime wherein said precast and pre-fired refractory block comprises in-situ mullite forming alumina silicate castable including metallic fibers.

A still further aspect of the present invention is directed to said roof mountable burner module adapted for enhanced life requiring less downtime wherein the said precast and pre-fired refractory block comprises in-situ mullite forming alumina silicate castable including metallic fibers comprises of 97 to 99 wt % castable and of 1 to 3 wt % metallic fibres.

A still further aspect of the present invention is directed to said roof mountable burner module adapted for enhanced life requiring less downtime wherein said metallic burner module comprises metallic outer enclosure having gaseous fuel inlet pipes , primary combustion air inlet openings and secondary combustion air entry openings preferably obtained of stainless steel.

A still further aspect of the present invention is directed to said roof mountable burner module adapted for enhanced life requiring less downtime wherein said precast and pre-fired refractory block is fitted securely with respect to said metallic burner module involving locking pins.

Another aspect of the present invention is directed to said roof mountable burner module adapted for enhanced life requiring less downtime comprising locking pins of stainless steel suited for refractory applications.

Yet another aspect of the present invention is directed to said roof mountable burner module adapted for enhanced life requiring less downtime comprising said metallic burner modules supporting plurality of burners for firing of gaseous fuel.

The above and other aspects and advantages of the present invention are described hereunder in greater details with reference to the following accompanying non limiting illustrative drawings.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWING
Fig.1: Schematic view of existing curtain flame burner module.
Fig.2: Schematic top view of existing refractory burner block showing position of burner outer enclosure plates and primary combustion air entry pipe.
Fig. 3: Schematic side view of refractory burner block showing position of burner outer enclosure plate & primary combustion air entry pipe.
Fig.4: Schematic top view of the curtain flame burner module fitted with precast & pre-fired refractory block of present invention showing position of burner outer enclosure plates & primary combustion air entry pipe.
Fig. 5: Schematic side view of the curtain flame burner module fitted with precast & pre-fired refractory block of present invention showing position of burner outer enclosure plate & primary combustion air entry pipe.

DETAILED DESCRIPTION OF THE INVENTION WITH REFERENCE TO ACCOMPANYING DRAWINGS

This invention pertains to the modification carried out in the existing curtain flame burner modules having refractory blocks provided with Y-shaped metallic anchors. More particularly, the present invention is directed to a precast and pre-fired refractory blocks made of in-situ mullite forming alumina silicate castable added with metallic fibers for curtain flame burner modules. The precast and pre-fired refractory blocks are fitted into the metallic curtain flame burner modules with the help of locking pins; which keep the refractory blocks in their positions securely.

Fig. 4 & 5 illustrates schematically top and side views of the curtain flame burner module fitted with precast and pre-fired refractory block. The modified curtain flame burner module of the invention having its configuration comprising of a metallic outer enclosure plates of burner module (Part 1 and 2) having gaseous fuel inlet pipes, primary combustion air entry openings (Part 3), secondary combustion air entry openings (Part 4), a precast and pre-fired refractory block made of in-situ mullite forming alumina silicate castable added with metallic fibers (Part 5) and suitable nos. of locking pins (Part 6) of suitable size. The metallic outer enclosure plates of burner module (Part 1 and 2) and metallic fibers are fabricated with stainless steel in order to withstand the high temperature. The locking pins (Part 6) are made with stainless steel or suitable refractory materials in order to bear load of refractory blocks at the high temperature. The refractory block (Part 5) is fitted securely into metallic outer enclosure plates of burner module (Part 1 and 2) with the help of metallic pin (Part 6).

To get rid of this problem, precast and pre-fired refractory blocks for curtain flame burner modules were manufactured from a user friendly in-situ mullite forming alumina silicate castable added with metallic fibers. To fit this special castable, burner modules were required to be redesigned with special anchors, increased space between burners and installed in ignition furnace of sinter machine. Precast and pre-fired refractory blocks were fitted in the metallic burner modules and installed in the ignition furnace of sinter machine. Burner modules which used to be changed / repaired twice every year, now expected to be changed / repaired twice every 3 years after modification.
, Claims:We Claim:

1. A roof mountable burner module adapted for enhanced life requiring less downtime comprising :

metallic burner modules providing for burners for firing of gaseous fuels ;

said metallic burner module having metallic enclosure including gaseous fuel inlet pipes, primary combustion air entry openings and secondary combustion air entry openings;

said metallic burner module securely supporting precast and pre-fired refractory block suitable for ignition furnace.

2. The roof mountable burner module adapted for enhanced life requiring less downtime as claimed in claim 1 wherein said precast and pre-fired refractory block comprises in-situ mullite forming alumina silicate castable including metallic fibers.

3. The roof mountable burner module adapted for enhanced life requiring less downtime as claimed in anyone of claims 1 or 2 wherein the said precast and pre-fired refractory block comprises in-situ mullite forming alumina silicate castable including metallic fibers comprises of castable 97 to 99 wt % and of fibers 1 to 3 wt %.

4. The roof mountable burner module adapted for enhanced life requiring less downtime as claimed in anyone of claims 1 to 3 wherein said metallic burner module comprises metallic outer enclosure having gaseous fuel inlet pipes, primary combustion air inlet openings and secondary combustion air entry openings preferably obtained of stainless steel.

5. The roof mountable burner module adapted for enhanced life requiring less downtime as claimed in anyone of claims 1 to 4 wherein said precast and pre-fired refractory block is fitted securely with respect to said metallic burner module involving locking pins.

6. The roof mountable burner module adapted for enhanced life requiring less downtime as claimed in anyone of claims 1 to 5 comprising locking pins of stainless steel suited for refractory applications.

7. The roof mountable burner module adapted for enhanced life requiring less downtime as claimed in anyone of claims 1 to 6 comprising said metallic burner modules supporting plurality of burners for firing of gaseous fuel.

Dated this the 10th day of February, 2023
Anjan Sen
Of Anjan Sen & Associates
(Applicant’s Agent)
IN/PA-199