Thermal process of adjustment for process of continuous refining.

AS AFRICAN AND MALAGASY INDUSTRIAL PROPERTY PATENT

P. 887

In Yaounde (Cameroon) International Patent Classification: 21 c. n° 01861

OO.AJ ^ P.I.. 17 November 1965 to 16 hr l°mn requested to IO.A.M.P.I. (G.P. № 52255) by

residing in France.

4 February 1970 delivered

Publishes the ballot official n " 1 of 1970

PRIORITY:

Patent application filed in France

18 november 1964 sec./ no. 995. 301

at the same name.

- Method of thermal adjustment for continuous refining process. -

The present invention due to men

The Juan manual KINDELAN therein jockeys Bonilla and stone will. YSSIERE in their jobs have been entrusted by the applicant relates to heat control of a continuous refining facility,

5 this adjustment involved any conditions refining themselves.

It is well known that the sharpening it is to say the oxidation of carbon, silicon and third parties elements contained in the crude iron causes substantial heating of the melt pool,

10 heating which, despite the elevation of the point solidifi -

cation upon the transformation of the metal steel, maintaining the liquid metal. In a refining facility batch temperature increase of the melt pool is sufficiently large that the may be safely added cold solids. The addition of these 15 products intended to establish a desired quality metal at a temperature suitable for - maximum production. Thus added lime to facilitate reactions dephosphorization; carried out additions of prereduced ores or not to increase the weight of the load, it is to say the production; it deoxidizes the metal at the end of the operation by adding metal reducer as a product of the man's. The amount of these additives is variable because the invention seeks to obtain maximum production compatible with the quality to develop.

In a plant for the continuous refining, the problem is more delicate. It is desired to essentially build

a quality product determined at a proper temperature, but in some cases it is desired, further, that the flow rate of liquid metal to the plant output as constant as possible for to ensure the achievement of operations taking place upstream

and downstream and to avoid thermal losses. Indeed, if the flow rate becomes very low, it is understood that the heat loss per ton of metal, are substantially increased. The aim of the present invention is to provide a solution to this problem and achieve a thermal adjustment in a plant for the continuous refining any conditions clean reaction created by the thermal refining.

To this end, the present invention is

a method of heat control of a facility for Cl ' continuous refining of a liquid bath by summing products characterized in that performs said additions to varying temperatures to obtain a supply of heat quantity varying with the thermal conditions in said bath liquid, it is to say with the enthalpy of said bath.

The above method can further comprise the following features in combination with the aforesaid:

a) OQs performs an addition product both in cold and hot in a form, said form cold and hot said shape being distributed rate constant overall according to the thermal requirements of the liquid bath;

b) at the addition has) as cold

is a powdered product;

c) at the addition has) as hot

is a powdered product;

d) at the addition has) as hot

is liquid.

Shot products, can be understood to mean all products that may be introduced into a refining vessel:

the cooling materials such as ore prereduced or not, limestone and scorifying materials, such as the man's deoxidizing, andc remelted scrap...

As is comprises, the invention consists in adjusting the thermal condition of a continuous refining facility from the conditions created by the refining reactions themselves. In general the method according to the invention enables control of the additions such that the metal has prepared the composition and the temperature that is desired to be at any rate the metal refining.

However was sometimes interest to maintain the flow rate of liquid metal constructed substantially constant in order to achieve optimum production efficiency and also to ensure the achievement of installations located upstream and downstream from a continuous casting plant. It cannot therefore add products by simple considering the final temperature of the metal as it is often the case during a refining process is discontinuous. In a plant for the continuous refining it is then indicated to adjust the rate of addition products so that the instantaneously producing constnante remains. The following considerations will better understand this hypothesis.

It may happen that the metal produced in the refining vessel either too cold for example as the result of a content insufficient carbon bulk metal; it would thus decrease significantly the addition of cold materials, thereby

would have decreased the instantaneously producing

metal. This rate decreases would have not only for effect

of that is assigned to the stations downstream and therein causing a slowing, but also further cooling the metal in containers not functioning at full brightness and or the thermal losses would be increased.

With the present invention such disadvantages are avoided: it is sufficient to completely or partially replacing cold products by products which will cool molten preheated or less or altogether the metal, the overall rate of materials introduced into the refining vessel remaining constant, thereby ensuring a constant instantaneous generation. The additions may be made at different thermal levels to room temperature, either at temperatures of 800 to 1000 °c for solid additions, either to 1500 °c still to additions of liquids.

There may be also a mixed injection product

both hot and cold product and alternately hot and cold according to the thermal state of the liquid bath. In sum, the present invention is to provide metal to be produced at the enthalpy of adducts according to his needs.

A preferred embodiment involves the additions in pulverulent form, implementation which allows easy product absorption by the liquid bath and a uniform distribution of the powder particles in the entire metal mass.

The UPE in another preferred implementation,

the product is introduced in the liquid state; this may be particularly attractive for the addition of oxygen scavengers such as ferromanganese introduced upon completion usually in a special container benefiting adding preliminary heated is frequently desirable. May also be introduced in the liquid state from falls or remelted scrap whose use solid state be difficult in a continuous refining facility.

These products can be melted in a furnace that gas from the sharpening same.

All these additions are naturally set in accordance with the temperature of the liquid metal to make this measurement can be done by known means such as bushings placed under protective sheath in the bath, or by optical pyrometers.

Of course the solutions may also, to some extent, act as a flow regulator for the metal to be refined. If this rate decreases to upstream of the refining facility the present invention increases the supply of cold or hot, and for instant generation will not be affected.

The present invention will be illustrated by an example implementation, will not limiting, described further below with reference to the attached drawing whose single Figure represents the pattern of a continuous refining facility provided by the invention are improvements.

It has drawn in a container to 1

pig a continuous refining vessel 2 to which it is connected by a conduit 3. A lance 4 supplied with oxygen via a pipe 5 connected to a source not shown is for the refining of the melt. A hopper 6 containing prereduced iron ore powder supplies a lance 7 via a line 8 either directly or indirectly via a heater provided with a heating jacket 9 9a in which the ore is fluidization is heated to a temperature of 1000° C.; the heater 9 is connected to the conduit 8 by ducts 8a and 8b. A container 10 containing a scrap is remelted supplies the refining vessel 2 via a conduit 11. As well as intended by the invention the rates in cold and hot ore ore supplied to the container 2 through the rod 7 are adjusted in accordance with the thermal state of the bath liquid in the vessel 2; the same applies for the remelted scrap rate from the container 10. The temperature

the bath contained 2 is measured by optical pyrometer to the outlet of the container 2.

The container 2 supplies refined metal

a processing vessel 12 complementary via a line 13. The complementary processing includes deoxidizing the refined metal by the man's. This can be introduced either cold solid form through a hopper 14 feeding a line 15 is hot in a liquid to a container 16 feeding a line 17. Can naturally combine adding cold and adding hot as a function of the thermal state of the container 12, which is measured with the temperature by a thermo-couple 18. The metal produced is discharged from line 19.

It is well understood that the present disclosure is to be considered as only one example of implementation in any way limiting, and should not serve to limit the scope of the invention which could be imagine much variations and improvements of details, as well as consider the use

equivalent means without departing from the field of the present invention.