DESC:FIELD OF THE INVENTION

The present invention relates to an apparatus for hot slag processing which is a Rapid Pad apparatus to solidify and fragmenting the molten slag generated in steel making process. More particularly, the present invention provides an apparatus for quenching and breaking of slag comprising rapid pad(RP) strips sloping down with curvature, and sub entry intermediate basin(SEIB) to pour along rapid pad strips disposed at selective gaps and provided with vibratory motion, so as to cool and granulating the slag while sliding down the said rapid pad strips and thus solidifying. The invention thus proposes a cost effective process for solidification by quenching and granulation of slag from its liquid state instead of dumping in yard to make the slag handling easier. The present invention advantageously avoids any complex chemical process for quenching and granulation of the slag and is also environment friendly without consuming electricity, water, land area or fuel.

BACKGROUND OF THE INVENTION

In a steel making process, various byproducts are formed during the various reactions that are being carried out in the steel making operation. During this process slag is produced which is one of the major byproduct which is formed while driving out the undesired impurities present in the hot metal that is obtained from the iron making. It is well known that the hot metal is charged with few percent of scrap as a coolant. The process start by blowing/arcing and the slag formation takes place, after many chemical reactions. The steel is made either with the help of L D convertor or Arc furnace by complete removal of impurities from hot metal in the form of slag to make steel. After the steel is produced with slag floating over the molten steel due to the density difference, the tapping of steel is done from the furnace through a hole called tap hole. After the completion of tapping (means metal is collected in a steel ladle), then the leftover product is slag in the furnace. Then this leftover slag is completely dumped in the slag thimble provided. There will be metallic remains/particles that also flow with slag into slag thimble due to the slag metal mixing. This loss of metallic content directly affects the yield of the steel making because it is a processed steel and to recover the metal from that slag adds up to the cost of the steel making and also making the slag handling difficult due to slag and metal fusion which is very hard to break or disintegrate. The metal content in the slag means loss in money and this makes the process complicated and create very unsafe working condition.

In a conventional process of slag handling, slag from the steel furnace is bought to the yard and dumped in allocated area called PIT. After dumping of few numbers (prescribed quantity) of slag thimbles of some prescribed quantity as per the capacity of the slag pit as much it can hold, the slag is cooled with the help of water. It is well known that slag is a brittle and hard mass, bad conductor of heat and hence it is very difficult to process it further. As metal is present in it, it makes the processing even harder and lengthy. The slag is then is loosened after the cooling with the help of heavy earth movers but with many difficulties. This adds up to the cost of processing of slag and steel making because even disposal of gangue material is very important, and even if the metal present comes in contact with the cooling water there are possibilities to oxidation of the metal which is uneconomical to reuse.

In the conventional process there are many deficiencies which not only make the process difficult but also adds up to the cost of steel making and make the process too much unsafe and difficult. Some of the well known deficiencies of conventional slag handling and processing are as follows:

1. Usually the slag is dumped and cooled in a very vast area for further processing. The molten slag which comes in contact with entrapped metal and bonds up to form a hard cake of mass/bolder. This is very hard to loosen/break in to small pieces because of the hardness. However, it must be broken in small pieces for disposal.

2. Metal entrapment in molten slag is another problem by which the metal gets spreads with molten slag. After cooling, that area having metal gets hard and makes the process very much difficult. Due to the metal entrapped in molten slag the metallic losses will be more and steel making yield decreases.

3. Due to the hardness of slag, the use of heavy earth mover used for slag breaking is required for more period of time which results in noise pollution and fuel consumption is also more in this process.

4. Due to more dust formation on slag cooling, equipments and machines required more maintenance.

5. As the slag is loosened, it is disposed/sent to MRP(metal recovery plant) to recover any metallic content that is present in the slag, this adds up to the cost of the process of steel making process. In MRP first the steel mix slag is charged in a hopper and passed through crushers, screens and numbers of conveyers. Then the crushed particles is passed over the magnetic separator to recover the magnetic metal particles. The metal recovered will be in the form of coarse particles and also contains some slag particles. This slag has some amount of impurities like sulphur (S), phosphorous (P), silica (SiO2), alumina (Al2O3) etc. which is uneconomical for reuse and if used it adds up to the cost of steel making.

This process of conventional Metal Recovery Plant (MRP) is very lengthy process and it takes more time and requires more area. In this process dust generation is more, which is not environmental friendly and also uses more electricity, water, land, fuel, manpower and other heavy equipments and earth movers. Safety parameter wise, conventional slag handling/process is very much unsafe.

Thus there has been always a need for developing an apparatus and a method which would be adapted to facilitate the slag management procedure in a metal or steel making industry and solve the problem associated with the conventional Metal Recovery process. In other words the basic need was to develop an apparatus and a method which would efficiently recover metal content from the slag without generating dust and without involving resources like electricity, water, land or fuel, in safe reliable and cost effective manner.

OBJECTS OF THE INVENTION

The basic object of the present invention is directed to provide a Rapid Pad apparatus for quenching and breaking of molten slag generated during steel making involving rapid pad strips and sub entry basin for pouring, cooling, disintegrating the slag in small pieces for further processing in a safe, efficient, cost effective and environment friendly manner.

A further object of the present invention is directed to a Rapid Pad apparatus for quenching and breaking of molten slag wherein water is not used directly to cool slag and dust formation is avoided during slag cooling and breaking into pieces.

A still further object of the present invention is directed to an apparatus for quenching and breaking of molten slag wherein the slag handling and processing do not require electricity, water or fuel or use of vast land area.

A still further object of the present invention is directed to an apparatus for quenching and breaking of molten slag wherein simple to and fro vibratory motion provided to the rapid pad strips enable disintegrating the slag into small granules for further processing, thus requirement of any large capacity earth moving equipment for slag handling/breaking is eliminated.

A still further object of the present invention is directed to an apparatus for quenching and breaking of molten slag wherein rapid pad strips are selectively sized and provided with long curve path inclined downward such that the required cooling of molten slag is achieved during its travel down the slope.

A still further object of the present invention is directed to an apparatus for quenching and breaking of molten slag wherein the cooling system is working surface of rapid pad and accordingly the slag flow over the rapid pad is controlled with the help of the sub entry intermediate basin(SEIB) by tilting the SEIB involving an actuating mechanism.

SUMMARY OF THE INVENTION

The basic aspect of the present invention is directed to an apparatus for hot slag processing favouring efficient and environment friendly metal recovery comprising:

atelast one hot slag pathway assembly for quenching and breaking of the hot slag during motion thereon including (a) an inclined slag pathway having curvature adapted to carry the flow of liquid slag poured at top along its surface; and (b) vibratory means causing breaking of the slag in motion into smaller easily handlabale sizes while solidifying for subsequent collection and recovery.

A further aspect of the present invention is directed to said apparatus for hot slag processing which is a Rapid Pad apparatus for quenching and breaking of the hot slag from the Steel melting shop for further processing comprising

a rapid pad assembly comprising a plurality of rapid pad strips inclined with respect to vertical column and having curvature at the tail end of the rapid pad strips at the bottom, adapted to carry the flow of liquid slag poured at top along the surface of the rapid pad strips inclined downwards;

a sub entry intermediate basin(SEIB) disposed at top of the rapid pad on a supporting platform for allowing controlled flow of molten slag poured from slag ladle in to the said sub entry intermediate basin which is being passed on over the said rapid pad for desired cooling and solidification of slag;

said rapid pad is segmented in to a plurality of equal individual said rapid pad strips and placed at equal distance with a prescribed gap between every individual strips, wherein the numbers of rapid pad strips are odd in the rapid pad and every alternative rapid pad strips are provided with vibratory motion for breaking of slag into pieces of suitable sizes while solidifying;

a discharge mechanism at the bottom end of rapid pad assembly for collection and transportation of solidified and fragmented slag for further processing.

A further aspect of the present invention is directed to a Rapid Pad apparatus wherein each said rapid pad strips are supported and movably suspended on a vertical wall like concrete structure on the rear side of rapid pad with the help of corresponding hangers and a pin inside the hanger for hanging the rapid pad strips connected to co-operating groove cut at top end of rapid pad strips, having equidistant placement of individual hanger on the concrete structure for each rapid pad strip and half/full bearing mounted on the pin to support the movement of the strips.

A still further aspect of the present invention is directed to a Rapid Pad apparatus wherein said rapid pad strips are selectively provided with a particular prescribed gap forming the rapid pad assembly in which every alternative rapid pad strips are movable at the adjacent ones with too and fro transverse vibratory motion for breaking of slag into small fragments, being operatively connected to an actuating mechanism wherein different rapid pad strips have different striking time.

A still further aspect of the present invention is directed to a Rapid Pad apparatus wherein said sub entry intermediate basin(SEIB) is placed near the top front of the rapid pad and said SEIB is pivoted so that the SEIB can be tilted with an actuating/tilting mechanism.

Another aspect of the present invention is directed to a Rapid Pad apparatus wherein said sub entry intermediate basin(SEIB) can be tilted through desired angle involving a tilting mechanism to regulate the flow of liquid slag on the rapid pad strips at a controlled rate commensurate with the rate of desired cooling, solidification and fragmentation of slag during its travel down the inclination of the rapid pad strips.

Yet another aspect of the present invention is directed to a Rapid Pad apparatus wherein said sub entry intermediate basin(SEIB) is mounted on an horizontal working platform at the top portion of rapid pad assembly supported on steel column structure for convenience of operators.

A further aspect of the present invention is directed to a Rapid Pad apparatus wherein the cooling system is working surface of rapid pad comprising a cooling arrangement that is actuated as the flow of slag over the rapid pad is started and turns on the water cooling of rapid pad so that the slag is cooled/quenched over the rapid pad with spraying water on the pads or strips and the cooled slag is disintegrated with the to and fro motion of the rapid pad strips as the impact force exerted by the rapid pad strips the slag particles gets broken.

A still further aspect of the present invention is directed to a Rapid Pad apparatus wherein said discharge mechanism comprise a discharge chute below the rapid pad and a chain conveyer below the discharge chute for collecting and transporting the broken pieces of solidified slag.

A still further aspect of the present invention is directed to a Rapid Pad apparatus wherein a vibrating type screen is provided at the discharge end of the chain conveyer to differentiate the different sizes of broken slag for further processing.

A still further aspect of the present invention is directed to a Rapid Pad apparatus wherein said rapid pad strips having decreasing thickness from top to bottom and each rapid pad strip is made in three parts which are connected to each other to form a single rapid pad strip being connected by lap joint or bevel joint.

The above and other objects 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 DRAWINGS

Figure 1: is the Side view of the apparatus for quenching and breaking of molten slag from steel melting shop according to the present invention.

Figure 2: is the Top view of the apparatus for quenching and breaking of molten slag from steel melting shop according to the present invention.

Figure 3: is the Isometric view of the apparatus for quenching and breaking of molten slag from steel melting shop according to the present invention.

Figure 4: illustrates the upper portion of the rapid pad with grove.

Figure 4a: illustrates the prescribed gap between the rapid pad strips.

Figure 4b: illustrates the cooling arrangements for rapid pad.

Figure 5a, 5b & 5c: illustrates the top, front & isometric view of the SEIB.

Figure 6: illustrates the arrangement for mounting of rapid pad strips on wall like concrete structure on the rear side of Rapid Pad with the help of hangers and pins.

Figure 7: illustrates the working platform at top of rapid pad in front of SEIB.

Figure 8: illustrates the vibrating screen.

DETAILED DESCRIPTION OF THE INVENTION WITH REFERENCE TO THE ACCOMPANYING DRAWINGS

The present invention is directed to provide an apparatus for hot slag processing which is a Rapid Pad apparatus for quenching and breaking of molten slag generated during steel making involving rapid pad strips and sub entry basin for pouring, cooling, disintegrating the slag in small pieces for further processing in a safe, efficient, cost effective and environment friendly manner.

Accompanying Figure 1, 2 & 3 show the Side view, Top view & Isometric view of the apparatus for quenching and breaking of molten slag from steel melting shop according to the present invention wherein the following different components of the apparatus have been shown:
1. Sub Entry Intermediate Basin(SEIB)
2. Rapid Pad
3. Chain Conveyer
4. Operation/working Platform
5. Round Shaft
6. Concrete wall structure
Following different components/features of the apparatus have been shown in accompanying Figures 4-8:
7. Groove of rapid pad.
7&8. Prescribed gap between Rapid pad strips.
9. Structure for platform.
10. Cooling arrangement.
11. screen

It can be seen from accompanying Figure 1-3, that the apparatus for handling the hot slag from the SMS (Steel melting shop) for quenching and breaking of slag comprise of inclined rapid pad(2) with respect to the vertical column structure. The rapid pad(2) which is inclined to the vertical column has the curved tail at its end at the bottom. The Rapid pad(2) is segmented into equal individual rapid pad strips and placed at equal distance with a prescribed gap(7,8) between every individual strips. The numbers of rapid pad strips are odd in the rapid pad. Accompanying Figure 4a illustrates the prescribed gap between the rapid pad strips.

The rapid pad strips are grooved(6) at the top end such that the groove can fit in hanger and pin provided on the concrete structure(6) behind the Rapid Pad(2) assembly. Accompanying Figure 4 illustrates the upper portion of the rapid pad with groove. The round shaft(5) which is placed over the vertical column hosts the number of rapid pad strips over it. Accompanying Figure 6 illustrates the concrete structure(6a) with hangers(7a) and pins(8a) that hosts the individual half/full bearing(not shown in figure) from its left end to its right and the rapid pad strips are mounted over the half bearing. The odd number of rapid pad strips with a particular prescribed gap(7,8) forms the rapid pad in which every alternative rapid pad strips are movable at the adjacent ones with too and fro motion being operatively connected to an actuating mechanism(not shown in figure).

A sub entry intermediate basin(SEIB)(1) is placed near the top front of the rapid pad(2). The SEIB(1) is pivoted so that it can be tilted with a tilting mechanism(not shown in figure). There is a working platform(4) subsequent to the SEIB supported on steel frame structure(9). Accompanying Figure 5a, 5b & 5c illustrate the top, front & isometric view of the SEIB. Accompanying Figure 7 illustrates the working platform at top of rapid pad in front of SEIB.

To put the apparatus according to the present invention in operation, the molten slag is transported to the slag yard with the help of slag pot via slag pot transfer car, the slag pot with molten slag is lifted with the help of EOT crane and the molten slag is poured into SEIB. The SEIB enables to control the flow of the slag (slag is poured into the SEIB to regulate the slag flow over the rapid pad). The SEIB is tilted with the help of actuating mechanism(not shown in figure) to regulate the slag flow, once the slag started flowing over the rapid pad.

The cooling system of the apparatus is working surface of rapid pad. Accordingly the slag flow over the rapid pad is controlled with the help of the SEIB by tilting the SEIB. Once the flow over the rapid pad started the cooling arrangement(10) actuates and turns on the water cooling of rapid pad(2). Subsequently every alternative rapid pad strips is provided with to and fro motion, the slag is quenched over the rapid pad(2) with the cooling system(10) and the cooled slag is disintegrated with the to and fro motion of the rapid pad strips with the impact force exerted by the rapid pad strips the slag particles gets broken. Accompanying Figure 4b illustrates the cooling arrangements for rapid pad.

According to yet another aspect of the present invention there is the discharge chute below the rapid pad and the chain conveyer(3) which is below the discharge chute(not shown). The broken slag is discharged into chain conveyer(3) with the help of discharge chute. At the discharge ends of the chain conveyer(3), a screen(11) which is a vibrating type is provided to differentiate the different size. Accompanying Figure 8 illustrates the vibrating screen. The quenched and broken slag is discharged in to said screen(11) and sized slag fragments are transported for further required processing to be carried out.

It is thus possible by way of the present invention to provide a Rapid Pad apparatus for quenching and breaking of molten slag from steel melting shop in a user friendly and cost effective manner without requiring electricity, water, fuel and land area for dumping, favouring ease of slag handling in an environment friendly way by controlled flow of molten slag on rapid pad for cooling/quenching, solidifying and also simultaneous fragmenting to smaller size fractions for further processing, instead of dumping large volume of slag in yard.

,CLAIMS:I Claim:

1. An apparatus for hot slag processing favouring efficient and environment friendly metal recovery comprising:

atelast one hot slag pathway assembly for quenching and breaking of the hot slag during motion thereon including (a) an inclined slag pathway having curvature adapted to carry the flow of liquid slag poured at top along its surface; and (b) vibratory means causing breaking of the slag in motion into smaller easily handlabale sizes while solidifying for subsequent collection and recovery.

2. An apparatus for hot slag processing as claimed in claim 1 which is a Rapid Pad apparatus for quenching and breaking of the hot slag from the Steel melting shop for further processing comprising

a rapid pad assembly comprising a plurality of rapid pad strips inclined with respect to vertical column and having curvature at the tail end of the rapid pad strips at the bottom, adapted to carry the flow of liquid slag poured at top along the surface of the rapid pad strips inclined downwards;

a sub entry intermediate basin(SEIB) disposed at top of the rapid pad on a supporting platform for allowing controlled flow of molten slag poured from slag ladle in to the said sub entry intermediate basin which is being passed on over the said rapid pad for desired cooling and solidification of slag;

said rapid pad is segmented in to a plurality of equal individual said rapid pad strips and placed at equal distance with a prescribed gap between every individual strips, wherein the numbers of rapid pad strips are odd in the rapid pad and every alternative rapid pad strips are provided with vibratory motion for breaking of slag into pieces of suitable sizes while solidifying;

a discharge mechanism at the bottom end of rapid pad assembly for collection and transportation of solidified and fragmented slag for further processing.

3. A Rapid Pad apparatus as claimed in anyone of claims 1 or 2 wherein each said rapid pad strips are supported and movably suspended on a vertical wall like concrete structure on the rear side of rapid pad with the help of corresponding hangers and a pin inside the hanger for hanging the rapid pad strips connected to co-operating groove cut at top end of rapid pad strips, having equidistant placement of individual hanger on the concrete structure for each rapid pad strip and half/full bearing mounted on the pin to support the movement of the strips.

4. A Rapid Pad apparatus as claimed in anyone of claims 1 to 3 wherein said rapid pad strips are selectively provided with a particular prescribed gap forming the rapid pad assembly in which every alternative rapid pad strips are movable at the adjacent ones with too and fro transverse vibratory motion for breaking of slag into small fragments, being operatively connected to an actuating mechanism wherein different Rapid pad strips have different striking time.

5. A Rapid Pad apparatus as claimed in anyone of claims 1 to 4 wherein said sub entry intermediate basin(SEIB) is placed near the top front of the rapid pad and said SEIB is pivoted so that the SEIB can be tilted with an actuating/tilting mechanism.

6. A Rapid Pad apparatus as claimed in anyone of claims 1 to 5 wherein said sub entry intermediate basin(SEIB) can be tilted through desired angle involving a tilting mechanism to regulate the flow of liquid slag on the rapid pad strips at a controlled rate commensurate with the rate of desired cooling, solidification and fragmentation of slag during its travel down the inclination of the rapid pad strips.

7. A Rapid Pad apparatus as claimed in anyone of claims 1 to 6 wherein said sub entry intermediate basin(SEIB) is mounted on an horizontal working platform at the top portion of rapid pad assembly supported on steel column structure for convenience of operators.

8. A Rapid Pad apparatus as claimed in anyone of claims 1 to 7 wherein the cooling system is working surface of rapid pad comprising a cooling arrangement that is actuated as the flow of slag over the rapid pad is started and turns on the water cooling of rapid pad so that the slag is cooled/quenched over the rapid pad with spraying water on the pads or strips and the cooled slag is disintegrated with the to and fro motion of the rapid pad strips as the impact force exerted by the rapid pad strips the slag particles gets broken.

9. A Rapid Pad apparatus as claimed in anyone of claims 1 to 8 wherein said discharge mechanism comprise a discharge chute below the rapid pad and a chain conveyer below the discharge chute for collecting and transporting the broken pieces of solidified slag.

10. A Rapid Pad apparatus as claimed in anyone of claims 1 to 9 wherein a vibrating type screen is provided at the discharge end of the chain conveyer to differentiate the different sizes of broken slag for further processing.

11. A Rapid Pad apparatus as claimed in anyone of claims 1 to 10 wherein said rapid pad strips having decreasing thickness from top to bottom and each rapid pad strip is made in three parts which are connected to each other to form a single rapid pad strip being connected by lap joint or bevel joint.

Dated this the 18th day of January, 2016
Anjan Sen
Of Anjan Sen & Associates
(Applicants Agent)