FORM-2
THE PATENTS ACT, 1970
(39 of 1970)
&
THE PATENTS RULES, 2003
COMPLETE Secification [See Section 10 and rule 13]

1 Title of the Invention.
"Process for direct reduction of iron utilizing solid coal and producer gas in reduction reactor"
2 Applicant (s)
1 Applicant Radhe Renewable Energy Development Pvt. Ltd
Nationality India

Address Plot no. 2621/2622, Gate NO. 1, Road D/2, Lodhika GIDC, Kalawad Road, PO Metoda, Dist. Rajkot. (Gujarat), India
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 method for the production of direct reduced iron (DRI) from iron ore in a rotary kiln or a reduction rector by reduction with solid coal feed stock as well as producer gas/coal gas support with increased production rate per day at lowered costing in environment friendly manner.
BACKGROUND OF THE INVENTION
The sponge iron is mainly produced from raw iron ore by two different routes (a) by reducing gases (CO and H2) in a shaft furnace, and (b) through direct treatment with carbon containing compounds such as coal in a reduction rector.
Different variations has been incorporated in said routes in last few decades, with use of different sources for carbon feedstock in order to make the method more efficient in terms of efficiency of sponge iron production at minimized cost. In coal fired reduction reactor fixed carbon requirement are complied with fixed carbon present in coal being fed in the reactor. Whereas in gas fired reduction reactor fixed carbon requirement are met with natural gas having required amount of the fixed carbon for the reduction of iron ore.
Coal fired sponge iron rotary kiln for reduction of iron with coal base reduction is well known in the state of arts. In this route in one of the known method for direct reduction of iron with solid coal support in a rotary kiln, the solid coal is introduced in the kiln at three points, by virtue of the addition of feeding coal along with raw iron at upper end of the kiln whereas injection of coarse coal and fine coal at lower end of the kiln. In such process feeding coal at upper end mainly utilized to maintain the temperature of the bed area whereas the coarse coal generally of 4-8 mm and fine coal takes part in the reduction of iron ores and concurrently also maintains the required temperature inside the kiln. However in such methods it is found that the carbon content in resultant char is quite high leading higher coal consumption per ton of sponge production with higher smoke and fly ash ratio polluting the surrounding environment.

The system and method described in U.S. Patent No. 5531424 suggests the use of natural gas for the reduction of raw iron ores, despite being very efficient in sponge iron production with less pollution in surrounding environment, this method is quite expensive and not much widely acceptable due to requirement of natural gas that is hard to obtain in such large amount for a plant located away from the natural gas resources.
Further, European Patent No. 0916739 suggests the use of syngas produced during a partial oxidation gasification process of hydro-carbonaceous feedstock to produce a synthesis gas to be used as the feedstock in a process for the direct reduction of iron, which is theoretically may be quite efficient nevertheless is practically unviable as difficult to work successfully depending upon only synthesis gas support for reduction of iron ore due to lack of required amount of fixed carbon that is the crucial necessity of reduction process being carrying out in the reactor.
Hence, a need continues for an improved and viable process for production of sponge iron by direct reduction in a reduction rector providing an improved reduction process with higher efficiency at lower cost in environment friendly manner.
Therefore the present invention is proposed to solve the above mentioned problems in an economic and environment friendly manner and at the same time to provide a process for direct reduction of iron with higher Fe grade quality at lower consumption of coal in order to provide an efficient process with increased production rate of sponge iron at lesser cost in an eco-friendly manner.
OBJECT OF THE INVENTION
The major object of the present invention relates to provide a process for direct reduction of raw iron ore in a rotary kiln or reduction reactor wherein the reduction process is supported through solid coal feed stock at upper end and at lower end of the reactor as well as producer gas/ coal gas support injected at lower end of the reactor providing an improved reduction process with cost benefits.
In a preferred aspect, the invention presents the highly efficient process suggesting the use of producer gas/ coal gas at lower end of the reduction reactor replacing the

requirement of fine coal feedstock being injected at lower end of the reactor correspondingly permitting extra volume for more iron ore feedstock inside the reactor consequently increasing the sponge iron production per day at lower coal consumption leading cost benefit
In further preferred aspect, the invention presents the process with lesser discharge of smoke and fly ash in the surrounding environment due to lowered coal consumption making the process ecofriendly.
BREIF DESCRIPTION OF THE DRAWINGS
The invention will hereinafter be described by way of preferred embodiments with reference to the drawings, where the exemplary drawings refers to the specific size of reduction reactor with 100 Ton per Day (TPD) production capacity, wherein
Fig. 1 is a schematic structural view of the system carrying out the direct reduction of iron with solid coal as well as coal gas or producer gas support, according to the preferred embodiment of the present invention, wherein the component parts are as followed
1. Main Storage Open Hopper.
2. Closed Storage hopper,
3. Rotary Feeding conveyer,
4. Bunker,
5. Shell,
6. Rotary Grate,
7. Water seal for gasifier,
8. Steam pipe line,
9. FD blower for gasifier,
10. Air pipeline,
11. Gas pipe line,
12. Cyclone,
13. Water seal valve for gas pipeline,
14. Turbulent flame high pressure gas burner,
15. Pressure air pipe line,

16. Air Pressure blower with motor,
17. Air blower with motor,
18. Air pipe line,
19. Rotary cooler,
20. Sponge iron and char,
21. Magnetic separator,
22. Char collector bucket,
23. Sponge iron collector bucket,
24. Hopper for dolomite feed stock, 25.Hopper for feeding coal,

26. Hopper for iron ore,
27. Shell air fan(Quantity of shell air fan depends on capacity of kiln),
28. Inlet for course coal/ Injection coal,
29. After burning chamber(ABC),
30. Outlet pipe,
31. Waste heat recover system (Optional),
32. Electro Static Precipitator(ESP),
33. Chimney;
Fig. 2 is a schematic structural view of the sponge iron reduction reactor of the capacity of 100 TPD along with the connecting parts in accordance with the Fig.l, where the reactor is distributed in different zones, wherein the seven zones of reduction process occurring inside the reactor are as followed
34. Reduction reactor,
a. Zone 1,
b. Zone 2,
c. Zone 3,
d. Zone 4,
e. Zone 5,
f. Zone 6,
g. Zone 7.
According to one of the preferred aspect of the present invention, no. of zones being created inside the reactor may vary according to the production capacity of the reactor.

DETAILED DESCRIPTION OF THE INVENTION
Advantages and features of the claimed invention will be apparent from the following detailed description to be read in conjugation with the accompanying drawings. An improved process for sponge iron production utilizing solid coal feed stock as well as producer gas/ coal gas support, establishing a process with increased production rate at lowered coal consumption according to preferred embodiment of the present invention is described herein after. In describing the present invention any related known function or structures are not described in detail so as to not vague the gist of the present invention.
In the preferred embodiment of the present invention, a process for direct reduction of raw iron ore in a rotary kiln or reduction reactor wherein the reduction process is supported through feeding coal feed stock at upper end and coarse coal feed stock at lower end of the reactor as well as producer gas/ coal gas support injected at lower end of the reactor eliminating the requirement of fine coal(0-4mm) feedstock being pneumatically injected at lower end of the reactor in the state of arts, thus permitting extra volume for more iron ore feedstock inside the reactor consequently increasing the sponge iron production per day, undeniably providing an improved reduction process with cost benefits, establishing the most efficient and environment friendly process that releases lesser discharge of smoke and fly ash in the surrounding environment due to lowered coal consumption.
In further preferred aspect, the present invention demonstrates an efficient reduction reaction occurring inside the reduction reactor due to use of producer gas/ coal gas instead of fine coal (0-4mm) at the lower end of the reactor. The said elimination of fine coal feed stock reduces the quantity of coal consumption approximately 20-25% compare to method depended upon coal based DRJ imparting the cost benefits.
Fig. I illustrates a schematic structural view of the system carrying out the preferred method of direct reduction of iron with solid coal as well as coal gas or producer gas support, wherein the reduction process is distributed in different zones, according to the preferred embodiment of the present invention.
A gasifier (high pressure high velocity gas injection system) is combined with the direct reduction plant producing DR1, wherein the gasifier (high pressure high

velocity gas injection system) is used to prepare producer gas/ coal gas from the hydro carbonaceous material like coal (Indian/Imported), wood, charcoal lignite, petcock or biomass briquettes of specific size, which is passed by gas pipe lines (11) and injected into reduction reactor (34) through Turbulent flame high pressure gas burner (14) in order to introduce the gas with required velocity and balanced pressure inside the reactor (34) to complete the reaction inside the reactor (34), replacing the injection of fine coal at that point;
Feeding coal of preferred size 8-20mm is added in to the reactor (34) through the feeding coal hopper (25) whereas the feeding stock of iron ore is added to reactor (34) through hopper for iron ore stock (26) and dolomite if required can be added through hopper (24) into the reactor (34); and
Coarse coal of preferred size 4-8mm is added in to the reactor (34) through coarse coal inlet (28).
Fig. 2 illustrates a schematic structural view of the sponge iron reduction reactor with the capacity of 100 TPD, distributed in seven zones and other component parts associated with, in accordance with the Fig. 1 of the present invention, wherein from the different zones of reduction process occurring inside the kiln:
The feeding coal maintains the temperature inside the bed area and plays partial role in reduction process in initial zones created at upper part of the reactor i.e. 34a, 34b and 34c;
The coarse coal plays major role in conversion of iron ore into sponge iron by reduction and also helps in maintaining the temperature inside the bed area in middle zones of the reactor i.e. 34d, 34e and partially in final zone(s) created at lower part of the reactor i.e. zone 34f;
Injection of fine coal is replaced with the injection of producer gas/ coal gas that takes part in the reduction of iron ore and also helps in maintaining the temperature partially in partially in zone(s) created at the end of the middle part i.e. 34f and completely in the zone(s) created at lower part of the reactor i.e. 34g.
In further preferred embodiment of the present invention, said direct reduction is possible to be carried out in the different zones inside the reactor according to different production capacity of the reactor to be used, wherein the reactor with the 50 TPD capacity will be distributed in 5 zones, reactor with the 100 TPD capacity will be distributed in 7 zones, reactor with the 350 TPD capacity will be distributed in 10

zones and reactor with the 500 TPD capacity will be distributed in 12 zones thereof. With the increase in size of the reactor, size of the gasifier also increases to meet up with the gas requirement accordingly. Correspondingly size of the turbulent flame high pressure gas burner (14) varies depending upon the size of the reactor (34), along with the size variation of corresponding parts of the burner including Air blower with motor, Pressure air blower with motor, Control valve for air / gas; and Refractory for burner.
With this arrangement according to Figure I & 2, due to complete (100%) replacement of fine coal and partial replacement of feeding coal and coarse coal with producer gas / coal gas, coal consumption decreases as shown in the table 1 point no.
1 (Al), it can be understood that coal input is decreased around 20-25% as 0.350 T coal /Ton of DRI is required in present method instead of 0.485 T coal /Ton of DRI in conventional coal based DRI method. Further to this, due to decrease in feeding coal consumption, thus allowing extra volume for more iron ore feedstock inside the reduction reactor (34), according to point no. I (B) and (C) of Table 2 it can be understood that feeding of Iron ore increases per hour, accordingly per Day of feeding of iron ore increased from 156 TPD to 192 TPD. Hence, sponge iron production increases from 3.705 Ton per hour (TPH) to 4.560 TPH as shown in Table 2 point no.
2 (C), around 20-22 % increase in sponge iron production is observed. Metallization is increased up to 3-4 % with increased Fe grade ratio up to 2-3%.
TABLE 1: Coal Consumption on Direct Coal Firing v/s. Coal Gas Support

SN Description Unit Coal fired DRI Solid coal plus producer gas fired DRI

Feeding
rate
(Tph) Feeding rate
(T/T of DRI) Feeding
rate
(Tph) Feeding rate
(T/T of DRI)
1 Coal (FC at 37-38%)
A Feeding of coal
Al Feeding at upper end (8-20mm) TPH 1.8 0.485 1.6 0.35
A2 Feeding at lower end (4-8mm) TPH 2.6 0.70 2.5 0.55
A3 Injection coal/fine coal (0-4mm) TPH 1.2 0.324 NIL NIL
A4 Producer gas (20-5 0m, 40% FC) TPH NIL NIL 0.46 0.10
B Total coal consumption TPH 5.6 1.51 4.56 1

In further preferred aspect, from data displayed in table 2 it can be understood that total coal consumption per hour and therefore per T of DRJ is decreased from 1.51 TV T of DRJ to 1 T/T of DRI imparting greater cost benefits. Further to this, decrease in coal consumption also exhibits decrease in smoke and fly ash in the surrounding environment of the plant, making the process lesser hazardous compared to conventional processes, at economical rate.
TABLE 2: Sponge Production on Direct Coal Firing v/s. Coal Gas Support

SN Description Unit Coal fired DRI Solid coal plus producer gas fired DRI
1 Iron ore
A Grade % 61-62 61-62
B Feeding of Iron Ore TPH 6.5 8.0
C Feeding of Iron Ore TPD 156 192
2 Sponge production
A Conversion ratio of IO % 57 57
B Total Sponge production TPD 88.92 109.44
C Total Sponge production TPH 3.705 4.56
The data according to TABLE-1 & TABLE-2 exhibits output achieved by the preferred aspect of the present process, in terms of the feeding of iron ore per day and coal consumption per Ton of sponge iron production, wherein the specific reactor size, coal size, quality of coal and quality of iron ore / iron ore pellet are mentioned. This output may vary on reactor size, coal size, quality of coal & quality of iron ore / iron ore pellet thereof.
In further preferred embodiment, fix carbon requirement for reduction reaction may * vary depending upon the form of iron being introduced in the reactor. In case of iron ore, the fix carbon requirement for production of 1 T sponge iron from iron ore was 480-550 kg/T (may vary as per coal quality, iron ore quality) whereas in present method, fine coal requirement replaced with gas being introduced through high pressure & high velocity gas injection system, the fix carbon requirement is reduced around 360-440 kg/T (may vary as per coal quality, iron ore quality) whereas in case of iron ore pellet, the fix carbon requirement for production of 1 T sponge iron from iron ore was 400-480 kg/T (may vary as per coal quality, iron ore quality). In present method, fine coal requirement replaced with gas being introduced through high

pressure & high velocity gas injection system, the fix carbon requirement is reduced around 300-400 kg/T (may vary as per coal quality, iron ore quality). Here, it can be clearly understood, that in either case the amount of coal consumption is reduced around 20-25%.
The said invention is purposed to provide an improved process for high Fe grade sponge iron production with increased production rate at lowered coal consumption in order to provide the process with higher efficiency at lower cost, in environment friendly manner. Although the subject matter has been described with reference to certain preferred embodiments thereof, other embodiments are possible. Further, the range for the reduction reactor may vary from 50 - 500 TPD or even customized to all possible sizes of reactors depending upon the requirement thereof. Furthermore, replacement ratio of coal with gas can be modified in possible customized manner. As such, the spirit and scope of the subject matter described herein should not be limited to the description of the embodiment contained herein.

We Claim:
1. A process for direct reduction of raw iron ore/ iron ore pellet in a reduction reactor (34) where the reduction process is supported through solid coal feed stock, feeding coal at upper end (25) and coarse coal at lower end (28) of the reactor (34) as well as supported through producer gas that is injected at lower end of the reactor (34) via turbulent flame high pressure gas burner (14), permitting the extra volume for more iron ore feedstock inside the reactor (34), consequently increasing the sponge iron production per day, providing an improved reduction process with cost benefits in environment friendly manner, wherein the reduction process inside the reactor is distributed in different zones according to the size of production capacity of the reactor.
2. The process as claimed in claim 1, wherein said reduction reactor (34) is fed with feed stock consisting of iron ore, coal, and dolomite.
3. The process as claimed in claim 1, wherein said reduction reactor (34) is fed with feed stock consisting of iron ore, coal, or dolomite.
4. The process as claimed in claim 1, wherein said feeding coal added in the reactor at upper end (25) is of 8-20mm in size and coarse coal feed stock added at lower end (28) is of 4-8mm in size.
5. The process as claimed in claim 1, wherein said producer gas is prepared from the hydro carbonaceous material like coal, wood, charcoal or biomass briquettes, Lignite, Petcock in a gasifier (high pressure high velocity gas injection system).
6. The process as claimed in claim 1, wherein said introduction of producer gas completely replaces the requirement of the fine coal to be injected at the lower end of the reactor (34) and partially replaces there requirement of feeding coal and coarse coal.

7. The process as claimed in claim 1, wherein the feeding coal maintains the temperature inside the bed area and performs partial role in reduction process in initial zones created at upper part of the reactor.
8. The process as claimed in claim 1, wherein said coarse coal performs major role in conversion of iron ore into sponge iron by reduction process and also helps in maintaining the temperature inside the bed area, in the zones created at middle part of the reactor and partially in the zone(s) created at lower part of the reactor.
9. The process as claimed in claim 1, wherein said producer gas takes part in the reduction of iron ore and also helps in maintaining the temperature partially in zone(s) created at the end of the middle part and completely in the zone(s) created at lower part of the reactor.
10. The process as claimed in claim 1 to 9, wherein the coal consumption per Ton of sponge production reduces by 20-25% when the specific reactor size, coal size, quality of coal and quality of iron ore / iron ore pellet being used are as mentioned according to the Table 1.
11. The process as claimed in claim 1 to 9, wherein the feeding of iron ore per day increases by 20-22% when the specific reactor size, coal size, quality of coal and quality of iron ore / iron ore pellet being used are as mentioned according to the Table 2.
12.The process as claimed in claim 1 to 11, wherein the coal consumption reduces around 20-25% due to decrease in fix carbon requirement for production of 1 Ton sponge iron from iron ore was reduced from around 480-550 kg/T to 360-440 kg/T.
13.The process as claimed in claim 1 to 11, wherein the coal consumption reduces around 20-25% due to decrease in fix carbon requirement for production of 1 Ton sponge iron from iron ore pellet was reduced from around 400-480 kg/T to 300-400 kg/T.

14. The process as claimed in claim 10 & 13, wherein the output may vary on reactor size, coal size, quality of coal & quality of iron ore / iron ore pellet thereof.