FR2521870A1 - CONTAINER WITH REFRACTORY COATING AND METHOD OF USING SAME FOR THE CHLORINATION OF A TITANIFE MATERIAL - Google Patents

Abstract

CONTAINER WITH REFRACTORY COATING AND METHOD FOR ITS USE: A CONTAINER FOR THE CHLORINATION OF A TITANIFE MATERIAL CONSISTS OF AN EXTERNAL RETAINING WALL FORMING A CASE 1, AN INPUT DEVICE FOR MATERIAL 11 AND A DEVICE OUTLET OF GASEOUS PRODUCTS 4 WITH A BASE PROVIDED WITH DEVICES 5 FOR INTRODUCING A GAS INTO THE CONTAINER, THE ENCLOSURE HAVING A REFRACTORY COATING 2 AND THE BASE HAVING A FILLING MATERIAL 7; THE COATING, THE FILLING MATERIAL AND OR THE GAS INTRODUCING DEVICES ARE MADE OF A REFRACTORY CONCRETE CONTAINING AGGREGATE AND A BINDER WITH A HIGH ALUMINUM CONTENT CONTAINING UP TO 20 BY WEIGHT OF CALCIUM CHLORIDE; A METHOD OF USING SUCH A REFRACTORY FOR THE CHLORINATION OF A TITANIFE MATERIAL WHICH IMPROVES THE LIFETIME OF THE REACTOR IS ALSO DESCRIBED.

Description

The present invention relates to a coating container.

  refractory, in particular a chlorination apparatus and a

process of its use.

  During the use of a chlorination apparatus for the chlorination of a titaniferous material, the existing refractory materials wear out when used as coatings, which necessitates repairs or codly replacements at intervals. frequent We are looking for such chlorination devices

  having longer service lives between repairs.

  According to the invention, a container suitable for chlorine

  ruration of a titaniferous material comprises an outer retaining wall forming an envelope having a closed upper end

  and a base, an input device for introducing a titanium material

  nifer in the container and an outlet device located at the end

  upper mite or in its vicinity for the evacuation of gaseous reaction products, said base having devices for introducing a gas into the container and for distributing this gas on the horizontal transverse surface of the container, said retaining wall having

  a refractory lining and said base having a filling material

  wise refractory between the individual devices of introduction and

  distribution of said gas, said individual devices, 1 said

  clothing and / or said filling material being formed of a refractory concrete containing an aggregate and a cementitious binder with a content

  high in alumina containing up to 20% by weight of cal-

  cium added relative to the weight of said refractory concrete.

  Preferably, the cementitious binder has aluminum contents of at least 50% by weight expressed in A 1203 and better still aluminum contents of at least 65% by weight expressed in A 1203 relative to the weight of the binder The rest of the composition of the binder is

  generally made up of a majority weight percentage of cal-

  cium and small amounts of silica and iron with other ele-

  trace amounts Depending on the particular amount of aluminum, the amount of calcium varies from 25 to 40% by weight expressed as Ca O

relative to the weight of the binder.

  Overall, we want the specific concrete

  formed by mixing the aggregate and the binder generally has a com-

  position such that its aluminum content is 44 to 50% by weight expressed in A 1203, its silicon content is 40 to 45% by weight, expressed in SiO, its iron content is not more than 2% by weight expressed in Fe 203 and its calcium content of 4 to 7% by weight expressed as Ca O. The addition of calcium chloride to the mixture of aggregate and binder has been shown to increase the service life of the

  refractory concrete to a surprising extent This is particularly

  This is astonishing considering the destructive atmosphere prevailing in a chlorination device with the presence of chlorine gas, acid reaction products and certain unavoidable oxychlorides. A simple addition of calcium chloride would not have been considered useful before. , this addition is of considerable importance The amount of calcium chloride

  added is at most 20 years of the weight of the dry refractory concrete mixture

  keep quiet and preferably from 1.5 to 10% by weight.

  The chloride can be added in a dry form to the other ingredients, or otherwise, the chloride can be added in the form of a solution in water necessary to effect the setting

refractory concrete.

  The proportion of the aggregate relative to the binder is chosen so as to produce the required composition of the final concrete but generally, depending on the particular composition of the ingredients, 2.5 to 5 parts by weight of aggregate are mixed with 1 part by weight of binder La particularly preferred proportion of aggregate with respect to the binder is 3 parts by weight of aggregate for

1 part by weight of binder.

  The aggregate can have a large particle size, but, generally, its particle size is between 8 mm and the dust A typical useful aggregate is a clay

  calcined refractory of desired particle size.

  Sufficient water is added to the dry mixture

  health to obtain the required consistency and allow

  full of refractory concrete The mixture can be used by casting, using a cannon, application with a trowel or extrusion, as it

agrees.

  The container is particularly useful in the choice

  ruration of a titaniferous material to produce tetrachloride of

  titanium Chlorination is carried out in the presence of a reducing agent.

  carbonaceous, for example coke, by chlorine gas rising through a bed of reactants with speed and density

  such that the bed is kept in fluid suspension Norma-

  The material bed is heated to at least 8000 C to initiate

the chlorination reaction.

  The bed of titaniferous matter which, in particular

  Proudly suitable, consists of ilmenite or better of natural rutile, is retained in the chlorination apparatus on the base formed by a set of tubes or nozzles of gas distribution carried by a lower support plate A refractory material

  filling is arranged between the gas distribution tubes.

  The gas distribution tubes or nozzles may be formed of a refractory material similar to that used to form the

  coating Normally, a wind boot or a distribution chamber

  gas burner is located below all of the distribution tubes

  gas distribution, so as to fluidize the bed and carry out the reaction

  chlorination and it feeds the tubes from an inlet

appropriately located.

  A form of chlorination apparatus constructed according to the invention will now be described only by way of example with reference to the single appended figure which is a schematic section

a suitable container.

  The chlorination device consists of an envelope

  outer cover 1 having a refractory lining 2 The end

  envelope 1 is closed by a cover 3 carrying a

  coating and envelope 1 has an upper outlet 4 for pro-

  chlorination lines Through the base of the casing 1 is a set or network of gas distribution tubes 5 carried by a

  support plate 6, the spaces between the adjacent tubes 5 being filled.

  folds of a refractory filling material 7 similar to that formed

  mant the coating 2 Below the support plate 6 is a wind boot or gas distribution chamber 8 having an inlet 9

gas.

  During use, the bed 10 of the titaniferous material

  to be chlorinated is carried by the set of tubes 5 and there is an ori-

  inlet 11 through which the bed can be recharged during use. The invention also relates to a method of chlorinating a titaniferous material to produce titanium tetrachloride which comprises establishing a bed of a titaniferous material to be chlorinated and a reducing agent based on a container according

  the invention, heating the bed to the reaction temperature

  as well as the passage of chlorine gas through the gas distribution tubes so that it reacts with the titaniferous material and maintains the bed in fluid suspension and the harvest of tetrachloride

  of titanium produced by chlorination.

  The invention is further illustrated by the example not

following limitative.

Example

  Preparing a chlorination container having a base

  with a filling material that was poured from a metal

  concrete slab containing an aggregate consisting of refractory clay previously calcined and a cementitious binder containing a source of alumina at a rate of 71% by weight expressed in A 1203 relative to the weight of the binder, iron oxide to 0.25% by weight and a source of calcium at 27 7% by weight expressed as Ca O Calcium chloride is mixed with the water used for setting and added to the dry mixture The amount of chloride of calcium is 2.5% relative to the weight of the dry mixture A bed comprising a mixture of coke and natural rutile is formed on the base and the mixture is heated to the chlorination temperature Then chlorine gas is passed through the bed during a period of 1200 hours during which the material constituting the bed is added and evacuated

  continuously chlorination products through an upper part

container.

  After 50 days, the continuous chlorination operation is stopped and the interior of the container is examined after having left it

cool.

  A close examination of the base indicates that there has been little or no erosion of the surface of the coating and that the nozzles which have been poured from a mixture of conventional concrete are eroded in allowing the coating to protrude from their upper surface. A similar filler with no added Ca CI 2, when used for a similar period, is worn to the point that the nozzles themselves protrude from the surface of the

filling material.

  The lifespan of the filling material is believed to be

  pleating containing Ca C 12 is at least double that of a ma-

  filling without Ca CI 2 added.

  Of course, various modifications can be made by a person skilled in the art to the devices or processes which have just been described only N by way of nonlimiting example

  without departing from the scope of the invention.

Claims (7)

  1 Container suitable for use in chloru-   ration of a titaniferous material comprising an outer retaining wall forming an envelope (1) having a closed upper end and a base, an inlet device (il) for introducing a titaniferous material into the container and an outlet device (4 ) located at or near the upper end for evacuation   gaseous reaction products, said base having arrangements   tifs (5) for introducing a gas into the container and for distributing said gas over the horizontal cross section of the container, said retaining wall having a refractory lining (2) and said   base having a refractory filling material (7) between the dis-   individual positive for the introduction and distribution of said gas,   characterized in that said individual devices, said coating   and / or said filling material is formed of refractory concrete   shutter containing aggregates and a cementitious binder & high alumina content containing up to 20% by weight of calcium chloride   added relative to the weight of said refractory concrete.   2 container according to claim 1, characterized in that the cementitious binder has an aluminum content of at least 50%   by weight, expressed in A 12 3, relative to the weight of the binder and of pre-   reference of at least 65 X by weight, expressed in A 1203, relative to the weight of binder.   3 container according to one of claims 1   or 2, characterized in that the calcium content is 25 to 40 X in   weight, expressed as Ca O, relative to the weight of the binder.   4 container according to any one of claims   above, characterized in that the particular concrete forming said   coating and / or said filling material has an aluminum content   nium from 44 to 50% by weight expressed as A 1203, a silicon content from 40% to 45% by weight expressed as Si O 2, an iron content not exceeding 2% by weight expressed as Fe 203 and a calcium content from 4% to 7 X by weight expressed as Ca O.   A container according to any one of the claims   above, characterized in that the calcium chloride content is 1.5% to 10 t by weight relative to the weight of the dry mixture of refractory concrete.   6 container according to any one of claims   above, characterized in that the amount of aggregate is 2.5 to 5 parts by weight per 1 part by weight of binder and   preferably 3 parts by weight per 1 part by weight of binder.   7 container according to any one of claims   previous, characterized in that the particle size of the granu-   lat is between 8mm and dust.   8 Process for the chlorination of a titaniferous material,   characterized in that one establishes a bed of titaniferous matter with chlorine   rurer and a reducing agent on the basis of a constructed container   according to any one of the preceding claims, it is heated   the bed at the desired reaction temperature, chlorine gas is passed through the gas distribution tubes so that it reacts with the titaniferous material and to keep the bed in fluid suspension and the titanium tetrachloride thus produced is collected. chlorination process;