U.S. patent application number 10/037482 was filed with the patent office on 2002-09-12 for process of producing a mixture of iron ore and low-temperature coke.
This patent application is currently assigned to mg technologies ag. Invention is credited to Hirsch, Martin, Orth, Andreas, Weber, Peter.
Application Number | 20020124690 10/037482 |
Document ID | / |
Family ID | 7670337 |
Filed Date | 2002-09-12 |
United States Patent
Application |
20020124690 |
Kind Code |
A1 |
Orth, Andreas ; et
al. |
September 12, 2002 |
Process of producing a mixture of iron ore and low-temperature
coke
Abstract
Granular coal and preheated granular iron ore are charged into a
low-temperature carbonization reactor, in which temperatures in the
range from 800 to 1050 .degree. C. are produced by supplying gas
containing oxygen and by partial oxidation of the components of the
coal. In the low-temperature carbonization reactor, the granular
solids are maintained in a turbulent movement. From the upper
region of the reactor, hot exhaust gas is supplied to a solids
separator. The granular iron ore is preheated by means of the hot
exhaust gas and hot, granular mixture of iron ore and
low-temperature coke is withdrawn as product from the reactor
and/or from the separator. The low-temperature carbonization
reactor may be designed as fluidized-bed reactor or as pneumatic
conveyor section. The granular mixture of iron ore and
low-temperature coke is suitable e.g. for a melt reduction
process.
Inventors: |
Orth, Andreas;
(Friedrichsdorf, DE) ; Hirsch, Martin;
(Friedrichsdorf, DE) ; Weber, Peter; (Kobel,
DE) |
Correspondence
Address: |
THE FIRM OF KARL F ROSS
5676 RIVERDALE AVENUE
PO BOX 900
RIVERDALE (BRONX)
NY
10471-0900
US
|
Assignee: |
mg technologies ag
|
Family ID: |
7670337 |
Appl. No.: |
10/037482 |
Filed: |
January 4, 2002 |
Current U.S.
Class: |
75/448 |
Current CPC
Class: |
Y02P 10/134 20151101;
C21B 13/0033 20130101; Y02P 10/136 20151101 |
Class at
Publication: |
75/448 |
International
Class: |
C21B 011/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jan 12, 2001 |
DE |
10101157.1 |
Claims
1. A process of producing a hot, granular mixture of iron ore and
low-temperature coke, characterized in that granular coal and
preheated granular iron ore are charged into a low-temperature
carbonization reactor, in which temperatures in the range from 800
to 1050.degree. C. are produced by supplying gas containing oxygen
and by partial oxidation of the components of the coal, the
granular solids being maintained in a turbulent movement and being
supplied from the upper region of the reactor to a solids separator
from which a hot exhaust gas is withdrawn, that the granular iron
ore is preheated by means of the hot exhaust gas, and that a hot,
granular mixture of iron ore and low-temperature coke is withdrawn
as product from the reactor and/or from the separator.
2. The process as claimed in claim 1, characterized in that the
low-temperature carbonization reactor is designed as fluidized-bed
reactor or as pneumatic conveyor section.
3. The process as claimed in claim 1 or 2, characterized in that
the pressure in the low-temperature carbonization reactor lies in
the range from 1 to 10 bar.
4. The process as claimed in claim 1 or any of the preceding
claims, characterized in that highly volatile coal is supplied to
the low-temperature carbonization reactor.
5. The process as claimed in claim 1 or any of the preceding
claims, characterized in that the product of iron ore and
low-temperature coke has a weight ratio Fe:C of 1:1 to 2:1.
6. The process as claimed in claim 1 or any of the preceding
claims, characterized in that the granular mixture of iron ore and
low-temperature coke is introduced into a melt reduction process.
Description
[0001] This invention relates to a process of producing a hot,
granular mixture of iron ore and low-temperature coke.
[0002] It is the object underlying the invention to produce the
above-mentioned mixture in an inexpensive way. The ore-coke mixture
should be suitable in particular for use in a subsequent melt
reduction process.
[0003] In accordance with the invention, this object is solved in
that granular coal and preheated granular iron ore is charged into
a low-temperature carbonization reactor, in which temperatures in
the range from 800 to 1050.degree. C. are produced by supplying gas
containing oxygen and by partial oxidation of the components of the
coal, the granular solids being maintained in a turbulent movement
and being supplied from the upper region of the reactor to a solids
separator, from which a hot exhaust gas is withdrawn, that the
granular iron ore is preheated by means of the hot exhaust gas, and
that a hot granular mixture of iron ore and low-temperature coke is
withdrawn as product from the reactor and/or from the
separator.
[0004] The low-temperature carbonization reactor may be designed
e.g. as fluidized-bed reactor or as pneumatic conveyor section.
Usually, the pressure in the low-temperature carbonization reactor
lies in the range from 1 to 10 bar and preferably 2 to 7 bar.
[0005] Expediently, highly volatile coal, also lignite, is supplied
to the low-temperature carbonization reactor. The coal may also
contain water. The coal supplied to the low-temperature
carbonization reactor has grain sizes up to about 10 mm and
preferably up to not more than about 6 mm; the grain sizes of the
iron ore lie in the range up to 10 mm and preferably up to 6 mm. In
the product of iron ore and low-temperature coke, the weight ratio
Fe:C usually lies in the range from 1:1 to 2:1.
[0006] Embodiments of the process will be explained with reference
to the drawing. The drawing shows a flow diagram of the
process.
[0007] To a low-temperature carbonization reactor (1) granular coal
is supplied through line (2) and preheated granular iron ore is
supplied through line (3). Air for the partial oxidation in the
reactor (1) and for the fluidization and transport of the solids is
supplied via line (5) and enters the reactor (1) through a
distributor (6). Secondary air is supplied via line (4). In the
reactor, temperatures in the range from 800 to 1050.degree. C. and
mostly 850 to 1000.degree. C. are provided. The dwell times for the
solids in the reactor (1) lie in the range from about 2 to 20
sec.
[0008] Entrained by hot exhaust gas, the solids are supplied from
the upper region of the reactor (1) through the passage (8) to a
separator (9) designed as cyclone. The hot exhaust gases largely
free of solids flow upwards in a suspension heat exchanger (10), to
which granular iron ore is supplied from the outside through line
(11). This iron ore is preheated in direct contact with the hot
exhaust gas and supplied through line (12) to a cyclone separator
(13), from where the preheated iron ore is recirculated to the
reactor (1) through line (3). Exhaust gas is withdrawn via line
(14) and is supplied to a gas cleaning not represented.
[0009] Ore-coke mixture produced is withdrawn on the one hand from
the cyclone separator (9) through line (15) and on the other hand
from the lower region of the reactor (1) through line (16).
Usually, line (16) contains coarser-grained mixture than line (15).
A syphon (15a) expediently serves as pressure barrier. Via line
(16a), the solids mixture can be supplied to the further use, e.g.
in a melt reduction process. Such melt reduction process is
described e.g. in the U.S. Pat. Nos. 6,083,296 and 6,143,054. The
iron ore in lines (15) and (16) is already partly reduced as
compared to the ore of line (11), where usually 10 to 40% of the
oxygen contained in the original iron ore have already been
removed.
EXAMPLE
[0010] In a plant corresponding to the drawing, 170 t/h granular
iron ore are supplied through line (11), and 142 t/h granular coal
with 25.4 wt-% volatile components and 17 wt-% humidity are
supplied through line (2). Through lines (4) and (5) a total of
114000 Nm.sup.3/h air enter the low-temperature carbonization
reactor (1), by means of which the temperature is maintained at
950.degree. C. Through line (16a), 210 t/h mixture of ore and
low-temperature coke are withdrawn, which mixture comprises 16 wt-%
Fe.sub.2O.sub.3, 49 wt-% FeO, 28 wt-% carbon and 7 wt-% ash. The
process gas withdrawn via line (14) has a temperature of
518.degree. C. and the composition
1 CO 11 vol-% CO.sub.2 11 vol-% H.sub.2O 22 vol-% H.sub.2 15 vol-%
CH.sub.4 1 vol-% N.sub.2 40 vol-%
* * * * *