Composite iron pellets

Patent metadata

Field	Value
Publication number	US-10214788-B2
Application number	US-201515112820-A
Country	US
Kind code	B2
Filing date	Jan 28, 2015
Priority date	Jan 31, 2014
Publication date	Feb 26, 2019
Grant date	Feb 26, 2019

Abstract

Disclosed herein are methods and compositions for producing composite iron pellets comprising an inner core comprising iron ore and a reducing agent comprising a carbonaceous material; and an outer shell comprising unreduced iron ore. The resulting composite iron pellets can be used to produce direct reduced iron (DRI) with improved productivity while reducing gas consumption.

First claim

What is claimed is:

1. A composite iron pellet having a core and shell structure,
the pellet comprising:
(a) an inner core comprising:
i. iron ore; and
ii. a reducing agent comprising a carbonaceous material;

(b) an outer shell comprising unreduced iron ore;
wherein the composite iron pellet comprises at least 90 wt % Fe 2 O 3 , and wherein the inner core comprises from 88.0 wt % to 97 wt % Fe 2 O 3 and from 3 wt % to 9.5 wt % of said carbonaceous material; wherein the pellets are fired.

2. The pellet of claim 1 , wherein the carbonaceous material is coke, pet coke, char, or charcoal, or a combination thereof.

3. The pellet of claim 1 , wherein the composite iron pellet further comprises a binder.

4. The pellet of claim 1 , wherein the inner core thickness comprises from about 25% to about 75% of pellet's diameter, and the outer shell thickness comprises from about 25% to about 75% of the pellet's diameter.

5. The pellet of claim 1 , wherein the composite iron pellet comprises from greater than 0 wt % to about 1 wt % Al 2 O 3 greater than 0 wt % to about 3.0 wt % SiO 2 , greater than 0 wt % to about 1.0 wt % CaO, or greater than 0 wt % to about 1.0 wt % MgO, or any combination thereof.

6. The pellet of claim 1 , wherein the composite iron pellet has an average pellet size of at least about 12 mm.

7. The pellet of claim 1 , wherein the iron ore comprises particles having a diameter ranging from greater than 0 mm to 3 mm.

8. The pellet of claim 1 , wherein the outer shell comprises iron oxide in an amount ranging from greater than 88% by weight to 97% by weight, based on the total weight of the outer shell.

9. A composite iron pellet having a core and shell structure,
the pellet comprising:
(a) an inner core comprising:
i. iron ore; and
ii. a reducing agent comprising a carbonaceous material;

(b) an outer shell comprising unreduced iron ore;
wherein the composite iron pellet comprises at least 90 wt % Fe 2 O 3 , and
wherein the inner core comprises from 88.0 wt % to 97 wt % Fe 2 O 3 and from 3 wt % to 9.5 wt % of said carbonaceous material, wherein the inner core comprises from about 25 wt % to about 75 wt %, and the outer shell comprises from about 25 wt % to about 75 wt %; wherein the combined weight percent value of all components does not exceed about 100 wt %; and wherein all weight percent values are based on the total weight of the pellet.

10. A method for producing a composite iron pellet of claim 1 ,
the method comprising the steps of:
(a) forming a mixture comprising iron ore and at least one reducing agent comprising a carbonaceous material;
(b) producing a shaped composite iron pellet;
(c) drying the shaped composite iron pellet; and
(d) firing the shaped composite iron pellet.

11. A method for producing iron, the method comprising:
(a) providing the composite iron pellet of claim 1 ;
(b) charging the composite iron pellet to a furnace; and
(c) reducing the composite iron pellets in the presence of reformed natural gas to thereby provide iron.

Assignees

• Saudi Basic Ind Corp

Inventors

• Saddik Mohamed Bahgat

Classifications

• C22B1/245

  with carbonaceous material for the production of coked agglomerates · CPC title

• C22B1/2406

  pelletizing · CPC title

• C21B13/0046 Primary

  making metallised agglomerates or iron oxide · CPC title

• C21B13/0073

  Selection or treatment of the reducing gases · CPC title

• C21B13/02 Primary

  in shaft furnaces · CPC title