Iron ores treatment apparatus

A fixed bed reactor specially adapted to be used in the gas-solid reaction for the production of sponge iron. The flow of gas is ascendant, entering at the bottom through a gas distributor specially designed to assure a uniform gas flow.

BACKGROUND OF THE INVENTION 
The apparatus in this invention is characterized by gas entries located in 
the bottom; usually in the related art, the gas entrance is at the top and 
the outlet is at the bottom; The disadvantage of having descendant flow is 
that at the bottom the reactor usually has a very bad gas flow, which 
requires in this zone an inert material, reducing the operation space in 
the reactor which causes problems with subsequent separations of this 
inert material from sponge iron. 
Another disadvantage of the known art is that the gas recollection is 
achieved by a plenum in frustum-conic form which is usually metallic and 
must be cooled with water by a coil. In the fixed bed reactors with 
descendant flow, there are in the plenum exit particle entrainment due to 
the high velocity of the gas reached at this points. 
SUMMARY OF THE INVENTION 
It is then accordingly an object of the present invention to overcome these 
disadvantages, since our art with the ascendant flow has a gas irrigation 
through all the load of ore in uniform form. Cooling is not required in 
any section of the reactor and particle entrainment is avoided since the 
gas outlet is at the top having all the transverse area of the reactor as 
a free area of flow.

DESCRIPTION OF THE INVENTION 
Referring to the drawing, the gas enters through the gas entries (1) which 
could be one or multiple (in the drawing, two are illustrated). Said 
entries are insulated since the gas received is hot in the order of 1700 
to 1900 F. (800 to 1000 C.) Subsequently the gas is distributed by a ring 
(3) and through the channels (4), is injected to the reactor. In order to 
have a better gas distribution, the flow transversal areas (2) of the said 
distribution channels (4) may increase alike the entries (1) withdraws, in 
this way the pressure drops are uniform through said channels (4), so the 
flow in each channel (4) is the same, with this, the uniform gas 
distribution is assured. The inclination of the channels can be 35.degree. 
to 45.degree. down. It was found experimentally that in this range the gas 
reaches until the upper part of the cover (5). The angle of 45.degree. is 
preferred to avoid stickness of sponge iron to the walls of the furnace to 
unload it through said cover. 
The cooling gas entries (6) are as close as possible to the hot has entries 
(1) having a cool gas entry (6) for each hot gas entry. This is in order 
that during the cooling cycle of the sponge iron the cooling gas is 
distributed in the same way of the hot gas. 
The gas outlets (7) are located at the top of the reactor the number of gas 
outlets (7) may be the same as the gas entries (1) though it was 
demonstrated experimentally that if a uniform flow is desired the gas 
outlets (7) must be at least two. 
The reactor has two sealing covers (5) and (8), the upper (8), where the 
reactor is filled, and the cover (5) where the reactor is unloaded, each 
have automatic mechanisms to open and close. 
The reactor has a body with a spherical shape at the top, cross section 
cylindrical at the middle and inverted frusto-conical bottom.