BE403967A - - Google Patents

Description

       

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  'PROCESSING / LATERITIC MINERALS "
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 The invention relates to a method of recovering nookel from ordinarily hydrated earth oxide ores containing small amounts of nickel and greater amounts of iron, generally much larger amounts. often called laterite ores; in this process the nickel of the dried ore is made soluble at high temperatures, taking the form of nickel chloride, by the chlorinating action of HCL gas, while the chlorination of iron is reduced or prevented by the action of H20 gas.



   Descriptions of lateritic ores.



   The process which is the subject of the invention relates more particularly to the treatment of oxide ores containing small amounts of nickel and large amounts of iron, usually 1 to 3% nickel and 30 to 60% iron. The natural unmodified ores are of

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   characterized by the presence of a lot of hycroscopic water, that is to say, water extracted by heat to the point,
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 C'1) jU <; I + P above the boiling point of water; and also - Ip.7nt. In the presence of combined water, that is, water not developed by the ore to the point, or just to the boiling point of water.

   The accepted time frame for the determination of hygroscopic water is 11000, Hygroscopic water often approaches 30 10 and, in such cases, is rarely less than 20. The combined water is often up to 10-13 (on the product released from hyoscoic water) and rarely reaches less than 7-9, (Combined water appears to be present in the form of "minerals such as gcethite (Fe03.H30), diaspore A10 (H)) and bauxite (Al20 (OH) 4).

   Although most of the metals present appear as oxides or hydrated oxides, there are usually small amounts of residual silicates, and the combined water is free.
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 a '.' cuTI. doubt present as water of composition of these silicates. Typical examples are found in Cuba, Puerto Rico, English West Africa and the Dutch East Indies; others less typical in Greece.

   These mine-
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 raiJ ie ordinarily find iron-containing material as residual surface blankets and are believed to derive from basic underground rocks at the
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 series of tropical or semi-tropical erosion; The term "lateritic minerals" is frequently used to denote these ores, and without being limited to any theory as to the origin of these minerals, this term will be used to denote the special class of ores for the processing of which the invention is intended. - born.

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   The hygroscopic moisture of lateritic ores is easily removed largely by exposure to reasonably dry air, at ordinary temperatures, and is rapidly and completely removed4 at 100-110 c,
The combined water, on the contrary, is not quickly and completely extracted, even at 50,000. Much of the combined water of samples from Levisa, Cuba, starts out slowly at 250 - 275 0; after 16 hours, at 250 0, a sample showed a content of 3.2% combined water;

   after 40 hours, 2.8%. Twenty minutes at 325 C reduced the quantity of combined water to the same degree as 16 hours at 250 0. The evolution of combined water by heating is irreversible to a very high degree.



   When it is completely dried as is usually done, that is, when the hygroscopic water is completely entrained. the ore is notoriously powdery, unless it is heated to, or above, temperatures causing agglutination, concretion, etc.



   Methods already known.



   Chlorination processes have been proposed for the treatment of nickel-iron ores in general, and garnierites (ores of ferro-nickel silicates) in particular, with various metal chlorides, in autoclaves at 190. C or below with a solution of ferric chloride; at temperatures approaching red with a salt (NaCL); at intermediate temperatures with magnesium chloride.

   Roughly pure HCL has been tested around 400-500 0.

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 nn has proposed methods comprising a large
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 temperature pool, chlorination - from the "flormale" to the heat ¯eue - and using similar ferrous chlorides m.1, often with H01 or 012 as equivalent on the other , and working over at least part of the temperature range with lead, humidified or soon re-humidified, A large part of the proposed processes had
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 lA for failure not to give good nickel yields;

   4 LP24 "'f" "' er G <.." 'l'l. of 6o "" - - it had + @ 4necessary in most cases to form
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 7 'iron chloride with all the iron in the ore or a large part of this iron, and to work the iron chloride at least by 149 - Passing through mechanical furnaces (with stirring), often vaporizing this iron chloride or dissolve it, and work it after in some way.

   These products do not contain any teaching
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 "I) or1 'obtaining high nickel yields while avoiding the need for handling, or forming with the ore quantities of iron chlorides, or the like,
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 very large compared to chlorinated nickel
These known procedures have in many cases been proposed as being able to be applied without modification to
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 miPrais of oxides prepared by oalcination.



  Aims of the invention
Lateritic ores exist in ± standard quantities in favorable places, and in surface deposits that smell mined without great expense with shovels.
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 or excavator - s k steam. Near the northeastern coast of Cuba, for example, there are deposits believed to be in excess of only 1 trillion tonnes. These deposits probably include the largest nickel reserves.

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 du mone, but they are not yet considered as such because there is as yet no sufficiently economical method for the extraction of nickel.



   A main object of the invention is to provide a very economical method of extracting nickel from these ores, a method based on the discovery of certain particular properties.



   Other detailed goals still include; - Obtaining high nickel contents, by the solubilization of the latter up to 90-98% while making soluble, even at the beginning, only small percentages of the large quantities of iron present; - The carrying out chlorination operations in inexpensive stationary reactors constructed of iron, wholly or largely, which eliminates the convenience of dust, refractories, and furnace capital and labor costs rotary or mechanical furnaces;

     Obtaining extreme gas perfection - solid contact and countercurrent dentitions, and by ensuring complete efficiency and volume of the reactor and reagent use, while eliminating the need for briquetting, the need for '' have foreign binders, or agglutination, concretion, etc ...



   - Enables the production of highly concentrated washing solutions without evaporation or the use of mechanically actuated counter-current devices; - Produce solutions of nickel, first comprising a small quantity of iron, or at will almost free of iron, and obtain economical wet methods for separating cobalt from nickel.

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     Obtaining means allowing, particu- larly by virtue of the concentration of nickel solutions
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 o-enuas, to economically recover the combined chlorine which '=' is contained, under a gas farm that can be reused '' for chlorination, while the nickel is obtained under turns of oxide ready to melt without the need for intensive use precipitation products for nickel, and in this
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 O1 4'ideas and others, to obtain an extreme economy of use of chemicals.
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 Other objects of the invention will become apparent from the description which follows.
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  General description of the invention.



  The process generally comprises the preparation of the ore, consisting of drying to remove the hygroscopic water and usually com-
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 bin'e and preferably, but not necessarily, the reduced- + ir? t ore into pieces all of about the same size; this -1-raitem-n + can comprise the classification operations for the removal of the ore called "shot" and the C "ncPn-a1-r dow nickel in the material to be treated;

   near dry chlorination operations at 4 "1-c, r6es temperatures, in which large percentages of the 3sn + iiakel are cc ,,. i-, re-r4, is to chloride at temperatures above- gSS e 3C'T = 'decn'-és 0., e + usually much above 0 degrees C., while dP only small percentages of the iron present are converted to chloride, used + ion of chlorinating power of hydrochloric acid and the restrictive power of vapor, the strength of
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 maximum chloru-ration of gases having a correlation with te: érafi.n.re;

   the chlorination treatment can be ordinary, is not necessarily, followed by the treatment
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 with weak Aes? az plv. 9 (including oxidizing agents

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 possible in controlled quantities) and at higher temperatures, to destroy iron chlorides, etc., to sweep away the HOl, and, in some cases, to make the pieces washable, which, by protecting NiCl2 from the destruction, by maintaining a sufficient quantity of HCl, and if possible, of C12, in the az of destruction;

   cooling the chlorinated ore and washing it to retain solutions containing nickel chloride preferably, but not necessarily, by backwashing, with fiscal layers of chunks of chlorinated ore, to contain concentrated solutions, and then working the solutions for the nickel preferably, but not necessarily, by agents including heat, and the force of hydrolysis of water, for the recovery of the combined chlorine as mixtures gaseous hydrochloric acid and vapor which can be used in the chlorination process.



     Some of the most important remarks.



   (a) Differential chlorination -: As we know, NCL gas will chlorinate the iron content of lateritic ores completely or almost. This action has been used analytically, and has been made the basis of the processes. It has been found that the chlorinating effect of HCL on the iron content of these ores can be prevented or greatly reduced by the presence of appropriate amounts of water vapor - H2O gas. In this way it has been found that it is possible to chlorinate 90-98% of the nickel while chlorinating only a small percentage of the iron - rarely more than 15% and often less than 5%.



  If there is + rop OF water vapor, the CHLORINATION of nickel

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 to a satisfactory extent is also prevented. he
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 However, a sufficiently large range of gpzeusew compositions which can be used for the entire range of temperatures eV-oloy-4 es;
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 The maximum temperature at which the true chlorine
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 = differential ration is satisfactorily achieved is, with most ores, around 275 degrees 0. Better results are usually obtained at and above 300 degrees 0.

   Chlorination differs from T3 u-being started at lower temperatures, around 40 degrees O., but attempts are made below this temperature to complete the chlorination. ¯ of nickel generally result in
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 excessive iron chlorination and other adverse results
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 a .7euxl.
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 Fear gives? high nickel contents, the
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 cer-'ace by volume of HCl in mixtures of H01 gas and water must be brought to certain densities - Dour na particular ore and at partner temperatures, etc .., - but it has been found that the greater part of the HCl when combined by the constituents of the mineral will be supplied at lower concentrations.
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 high.

   This effect is so extreme that a demanding ore
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 gases containing about 50 volumes per cent IR01 move 03% nickel chlorination at 250 degrees C
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 ('\ fi, zp.



  1511, 9 k 9 2 r-M -
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 ypt,. this temperature, when it is still / to remove ùt1 copl ± + e # in very dilute HCl - H20; steam
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 stinks escaping. The same Kinerai sees its chlorinated nickel content up to 40 <at this temperature before requiring az containing more than 12 volumes per cent of HCl.

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   (b) Reactivity. Nickel in natural lateritic ores has been found to possess the ability to react with HCL gas, under selected circumstances, as stated, which is seriously diminished by. heating at and above certain temperatures and for times which vary somewhat with the different minerals. The decrease in reaction power appears to be approximately parallel to the decrease in combined humidity below the figure achieved for ore processed by long exposure to a temperature of 190 to 200 DEG C.

   Cuban lateritic ores are not deteriorated by prolonged heating at 200-225 degrees C. for the last treatment at 190-210 degrees, but are slightly so, if they are for the last treatment at 250 degrees . But, if they are heated so little at 550 degrees, or for 10 to 20 minutes at about 25 degrees, or for 20 hours at 250 degrees, the yield after the preferred treatment at 250 degrees which, on fresh ore, would have been 90-94%, d0sdendra up to 40 - 50% and the yield following the preferred treatment at 190-210 degrees which would have been 95-98% will fall below (the 50 %, The water combined in the damaged ore is found in an amount ranging from 2.8 to 4.3% in the various cases.



     It will be understood that the reactivity which has been discovered is differential with respect to iron: the failure of the nickel ores to react with the HCAL gas almost completely, under conditions where the iron ores present react little. It is this relative or differential reactivity, which is lost by overheating, as stated above. The absolute reactivity is not lost; the nickel contained in the heat damaged ore will react completely with an HCL

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 strong enough and in sufficient time, even at 300,
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 -car er.er'ç '' e, but the, fe 'is also then largely, and even completely chlorinated.



  No hypothesis is advanced in accounting for this phenove- ne, which is most remarkable in that nickel often retains activity after excessive heat. (c) Pieces: Identical ores (unless they are charred, etc.) are notoriously powdery
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 when working them dry, and it is known that it is difficult to wash them afterwards, because it is necessary to handle huge volumes of sludge giving insi-
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 m-rif-binders.

   It has been found that these minerals can be broken up in various ways, without damaging the reactivity of nickel (such as by calcination) or without great expense or e: ene in the chemical part of the process (such as by biOUtae, by example with organic binders); that these pieces are sufficiently porous to react completely dead when they reach $ + pnt 15 mm in diameter and T: '! us; they are strong enough to withstand moderately careful meninulsticn, and to support their own weight in deep loads;
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 cn rufl i Ast the most remarkable, they support the washing P- ne in désaqxéqeai:

   not water, if they are hydrated and, as we said above, which allows filtering or washing. A flowable "sand" ge with high porosity and easy flow through wash layers.



   Various other observations will be described later in the specification.

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   Ore preparation.



   A preferred method for the preparation of ore chunks is as follows: the natural ore as it comes out of the mine is broken up by passing it through toothed rollers; it is fed, together with a quantity of pulverized dry ore, to one end of a horizontal rotating steel cylinder, provided at its end / inlet with an inwardly projecting rim! By controlling the rotational speed of the cylinder and the supply of powder, the material discharged at the other end of the cylinder can easily be made homogeneous in size. The discharge product is sieved; In an experiment, material smaller than 6 m / m and larger than 9 m / m was returned to the inlet end of the cylinder.



   Pieces of substantially the same size, comprised between 6 and 9 m / m 5, are then dried on a dryer similar to a straight line concretion machine; but of lighter construction due to the low temperatures involved. The maximum temperature of the hot gases supplied to the front box of the dryer was 2100 C., in one case.



  In order to achieve uniformity of drying and preliminary heating, the hot gases were sucked through the discharge end of the moving ore layer and then passed through the rest of the ore body. Twenty-five minutes were necessary for this drying and this preliminary heating operation. The ore discharged from the drying belt was fed directly to a chlorination reactor apparatus. This drying method fulfills the desirable condition of being able to easily adjust the drying time and the maximum temperature to which the ore is exposed.

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   In another preparation method, ore was processed from mines in Levisa, Cuba. This Binerai contained 18-20% particles larger than the 40 mesh friend + and 77% finer particles than the 200 mesh sieve. Matter bigger than
40 mesh was found in the form of hard rounded pieces, often called "ore in shot", and containing monk. nickel or fine particles. The natural ore was treated with water and the "shot" ore was removed by the well known means of water classification. This resulted in a certain concentration of niokel in the fine particles.

   The fine ore pulp was stripped from the water, filtered and the filter cake was dried at low temperature. The filter cake was then broken by known means to give the maximum of the desired size scale. pieces too large or too small, being returned and mixed into thick pulp ready for filtering. The pieces of substantially the same size were then subjected to final drying and pre-heating on a straight line concretion drying machine, AS above. previously described;
Definition of certain terms,
Hydrochloric acid, HCL, is not in this description the equivalent; elemental chlorine 012.

   When specifying me CL2, it is for a special purpose, entirely different from the purposes for which the HCL is used. Hcl would not perform the functions of cl2, nor would cl2 perform those of hcl in the process object of the invention
Latetitic ores often contain 6 to 14 kg of cobalt per 100 kg of nickel. The reactions

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 and the way cobalt behaves are for the most part very similar to that of nickel. nickel containing cobalt is very acceptable in many industries. The term "nickel" will be used in the description itself to denote the cobalt present, except where the context will not allow it or when the two are clearly different.



   Specific examples of the process.



     EXAMPLE 1
Minerailaterite from the deposit of
Pella Maria, near Levisa (Cuba), in the form of pieces with a diameter ranging from 22.5 m / m to 3.5 M / m and PRACTICALLY containing no "granal ore", was dried and brought to maximum temperature of about 175 degrees C. The temperature of the pieces was measured by a thermocouple covered and embedded in the mass. The dried ore contained 49.7% iron, 10.9% alumina, 2.17% chromium, 3.2 silica, 1.57 nickel and 8.7% combined water.



   The pieces were placed hot in a vertical iron tube, supported on a sieve at the bottom of the tube. The depth of the charge was about ten times the diameter. The tube was protected against any cooling and maintained at a temperature ranging from 265 to 27µdegrees 0.



  Steam was first of all passed through the ore charge containing a mere trace of HCl on arrival and coming from other reactor tubes carrying out the same treatment. The ore charge showed only slight resistance to gas flow; The outgoing gas consisted of steam released from HCL. Of these gases progressively richer and richer in HCL were brought to ENTER and reached 50 to 55 percent HCL volume after 40 minu. your. When traces of HCl appeared in the gases

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 outgoing, the latter were brought to pass through a similar load of another tube. Full force gases were blown through the tube for two hours.



   A sample of the chlorinated pieces then showed 90.2 water soluble nickel as chloride, only 2.82% of the total amount of iron was soluble. Of these 2.82%. 1.28 was soluble as iron chloride and 1.54% as ferrous chloride: d vapor containing only a small percentage of hcl was then blown through the feed, about 10% HCl at the start, to finish around 1 to 2% in a few minutes. This + raiterent lasted 30 minutes. The gases used for this treatment were the gases leaving other reactors carrying out the treatment.

   The gases leaving this operation, which is called here treatment for the destruction of chloride or hydrolysing treatment, were then passed over relatively fresh ore, ore which had not yet been under the influence. gases as strong as these output gases from the hydrolysing treatment.



   The nickel in the charge was then of the same schubility as before. There is no trace of ferric chloride. The ferrous chloride found previously was virtually identical. The load CONTENAILT OF HCL which WERE "flooded with hot flue gases at low + ENEUR in oxygen.



   The charge was then removed from the reactor - from which the pieces flowed easily - cooled and LIFT counter-corrected with water. The resulting solution contained 3Bn7% solids. The solids were crystallized by evaporation and consisted of nickel chloride and iron.

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   The cries +, waters were placed in a muffle furnace and heated to 550-650 degrees C. Air was sent and brought into absolute contact with the solids. These were converted into nickel oxide and Fe203. The outgoing gases contained, by volume, 49% HCl, 42% H2O, slightly more than 8% nitrogen and a 1% fraction of oxygen.

   These gases were used again in new chlorination charges and were about the same effective in chlorinating nickel and in preventing the chlorination of iron, as a mixture of 52 volume5 percent of HCl and 48 steam;
The mixed oxides were smelted with ferro-nickel. fXFMPLF 2
An ore similar to that used in the example was dried and brought to a temperature of 250 DEGREES c7, in a rapid stream of hot gases the temperature of which did not exceed 360 degrees. The ore was processed as in Example 1.

   The maximum strength of HO1 was 49 volumetric percent, the rest of the gas was vapor. After treatment with this form of gas, for two hours, a sample was analyzed and demonstrated that 95.5% of nickel was soluble as chloride; 4.4% of the iron present was soluble as ferric chloride and 2.1% as ferrous chloride. A small amount of prop aluminum present as chloride. The chlorinated ore was alsore treated with dilute GAS as in Example 1, for 30 minutes. The nickel solubility was then 93.2% almost the same, the difference was TRUELY due to the difficulty of precise sampling.



    0.6 of the iron present was soluble as ferric chloride and 2.2% as ferrous chloride. There is still a little soluble aluminum \ After cooling

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 p + 1, ra7 as in Example 1, strong solutions are obtained. Most of the combined chlorine in the solution was recovered as H2O gas and reused for the chlorination. The solutions contained in! 3} \ "Sld .. more iron / nickel proportion than could be obtained from the analysis of the sample. At least% ¯ Aq was found. This was partly due to the 11HOl contained in the ore which had dissolved in the washing solution and had reached the ore to a point when the solution had concentrated.

   In one operation, residual HCL had been partially removed by ventilation; in another, by continued application of vacuum, which can be watched. as a form of ventilation,
Although operations have been stated to be carried out at? FO and 270 degrees with fixed mine charges, it is usually preferable, when working at these temperatures, to do with a flow of ore. almost continuous, and discharging chlorinated material from the acon to decrease the risk of damaging the ore which is flowing into the drafter and waiting to be processed.



   .At 50-275 years, the evolution of the combined water from the ore during the chlorination dilutes the acid gases and special care must be taken to ensure that the gases have the desired strength in the mass. of ore, EXAMPLE 3
Oct the example sleeps several samples of this disastrous result given by heating a particular sample of ore for too long and, (or beats) at too high temperatures before chlorinating at around 250 C. In each example, the ore and the procedure is as in Example 2, except that

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 concerns the pre-heating and drying operation.



   Sample A was steamed to 250 ° C. until the combined water content dropped to 6.5% the solubility of nickel resulting from said chlorination treatment was 69%.



   Sample B was heated to 250 ° C., until the combined water fell back to 3.7%, After the chlorination treatment, the solubility of nickel was 44.5%,
Sample 0 was heated in vacuum at 250 until the combined water descended to 4.29%. The solubility of nickel was found to be 56.4%.



   Sample D was heated to 55 just long enough to be sure the ore really reached that temperature. The combined water reached approx. 1% nickel solubility was found, after chic. ruration, 35.2%.



   EXAMPLE 4.-
A certain batch of lateritic ore was reduced to pieces 6 m / m to 9 m / m in diameter, then dried in a rapid stream of waste flue gas containing a lot of oxygen. The maximum temperature of the drying gases was 2200 ° C., the ore then contained 52.3% iron, 1.78% nickel, 0.13% cobalt of 10.0 "% combined water.



   The hot ore is brought directly to the top of a reactor consisting essentially of a vertical iron tube, and there meets a stream of steam exiting to the waste. The reactor is protected against any cooling. The ore column = filling the reactor descends slowly as it is drawn from below. Going down, the ore sees its teniperature increase until around 195-210.
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 aevienT)

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 r.xo = ÇirRmen ": pl'JS rich in HCl and contains about 28, C '' ', \: !!, ps tie one hundred E01 at point B.

   At a point in the tube where mlinr = a5 has been exposed to 20 voles percent HCl, the so-? 2bi? .I- d-nickel is 56 percent; when exposed to "'P vo" mers ent 1'H01, the solubility of nickel is -Q01e>. Pr3s exposure to 28 volume percent HCl, the solubility of nickel is 95.8%. At this stage 4.92 of the iron + otal is present in the form of ferric chloride and 0.89 in the form of ferrous chloruff. Chlorinated ore contains 2.51% chlorine insoluble in water, which is
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 due in part to the presence of ferric oxychf & e FeOCl. Less than 41 of the total iron is found under this formal A sample
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 taken through a test opening at B, and washed with water results in a sludge.



   The B to 0 section of the reactor was doubled and CONTAINED an internal 10 heating coil.
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 ru 1: 9.T + internal erren and the coil are provided with aren; e device of heat and steam distribution 1 == ov ± nant from source # not shown. In this section, the temperature of the ore is raised up to Z70-a90 G. Des é µ - = n..iijo = s of mir.eai, xetir3s in 12 show that there is no fer- chloride. ique, ni oxyoh] Eia ferric, or only uncertain tTac = 's.

   Chlorine insoluble in water does not reach -paq oN 1%? Nickel and chloride, ferrous are found in mother quantity than in the sample withdrawn in 14. hcl and the vapors recovered from the solutions of the washing of NIGKEL CHLORIDE as described are BLOWN into the apparatus by the opening 14, and join the neck
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 As "1'9 '! 8.Z rising. A diffuser, not shown, spreads 1"' s; az amends in the upstream.

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   The section C D of the Reactaur must be made of a ferrous alloy of chromium and nickel 18-8. At 16, the gases extracted, according to the wishes, from the connections 18, 20, 22 of the pipe confrere by a valve along the section
A - B are blown there by a 24 fan. The connections are changed when necessary; so that these gases contain 8 to 12 volume percent HCL. Elemental chlorine is blown with these gases in small quantities, controlled so that the chlorine disappears in 1-, current rising around the inlet opening 12.

   At 24, a fan forces the extracted gases, as desired, from a second series of valve-controlled connections 26, 38, 30 even higher along section A through B, adjusted so that HO1 reaches a volume percent of about 2%. The volume of gases introduced at 16 and 24 is adjusted so that the rising gases at B reach about 28 volume percent. The ore is removed in D through a gas-tight door, not shown. Analyzes of samples show nickel chloride of the same nature as in B, and the absence of ferric chloride. Ferrous chloride is present in the form of eraces; 0.00045 to 0.00063 of the iron present is soluble as ferrous chloride.



   The ore will contain HCL, some contained in the porosities of the pieces and in the interstices between them, some may be contained in other unknown ways. The flue gas contained in small quantities in the oxygen is quickly blown down the pieces of ore for a few minutes in a separate container, which entrains this HCl. The ventilation gases pass over fresh ore intended to be fed into the reactor, at A, and the small amount of gaseous HOl is absorbed by the ore.

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   The pieces are then washed with filtered water while countercurrently. They don't fall apart. The washing is carried out in a series of concrete tanks with false bottoms the solution being pumped from one tank to another,
Solutions thus obtained contained 34.7% of parts
SCLIDES.



   In a laboratory test on an ore, sens-
ONLY free of manganese, under conditions similar to those previously described, 10OKgs of nickel were found; 7.99 Kgs of cobalt and 1? 52 Kgs of iron. About ten percent of the solution was drawn out of the remainder. The iron in this 10% was oxidized with calcium hypochlorite and the metals in this part all precipitated as carbonates and hydroxides in known manner. The above was washed, and added to the whole mass of the solution. Chlorine, C12, with a slight trace of bromine, was then introduced and the solution stirred.

   All the iron and cobalt in solution were precipitated, the iron as ferrious hydroxide, and the cobalt as cobalt oxide or cobalt hydroxide. The above was granulated and easy to filter. It contained basic nickel carbonate, which removed by stirring with fresh washing solution for similar purification.



  The aforementioned T, e was then washed, and the washing products. employed in preparing mixed carbonates and hydrfoxides for use as precipitating agents in FOUs; subsequent batches. The above contained only iron, small amounts of aluminum and cobalt, and was commercially free of all nickel. It was melted with ferro-cobalt. Another batch was refined until obtaining pure cobalt oxide by known methods.

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   The solution now containing neither cobalt nor iron, but diluted slightly, and not contaminated with NaCl, 3 CaCL2, etc., (as would have happened had it had or treated by ordinary methods), was then evaporated and Nickel chloride was thus crystallized. The hydrated scraps were calcined at low red heat in the absence of air. Nickel oxide and a mixture of
HCAL and H2O gas were thus produced. The gases were drawn back towards the reactor. Some of the nickel oxide was smelted into metallic nickel, and some was used to make nickel-chromium alloys.



   FYFMPLF 5
This example gives various results of the effect of using stronger acids than necessary or desirable.



   A - In one test, the nickel solubility of 92.6% was reached by chlorinating for 2 hours at 2500 c with 60 volume percent HCL. The chlorinated ore contained 1.65% iron as ferric chloride, 1.86% iron as ferrous chloride, and only a trace of FeOCL. This result was roughly satisfactory as seen by the other tests, but less iron would have been chlorinated with somewhat weaker acids and the solubility of nickel would have been just as good.



   B - In a further trial 90-95% HCL was emitted. bent at 250 degrees. The solubility of nickel was only 58% after two hours. (The sample had its combined water reduced to 3.8% before chlorination). The chlorinated ore contained 20.3% FeOCL. 34% of the total iron was chlorinated.



   C- With strong HCL (90 to 100%) at 2250 in two hours, on fresh ore, 40% of the iron was chlorinated.

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  D - the operation at 270 degrees with 70-74 uonr cen volumes of FCl gave a solubility of the nickel substantially the same as in Example 1: 89.7 5. But the iron chloride had increased, and amounted to 6.8 instead of 2.82% of said Example 1.



   F- In another test showing the bad ef- fects of an acid stronger than necessary, 38 volumes
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 100% acid had been used at 190-200 0. The nickri was + soluble at 93. 27% of the total iron was chlorinated.



   F - The ore was chlorinated for four hours
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 at 0-lOo C with 50 percent volume of R01. The nickel was completely chlorinated, and the iron 85%. Of the amount of 'and present, 48% was as FeCl3, 6%
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 FeCl2, and 33 FeOCl.



  'ry1i'1fDtF 6 This example shows the gas effects of forcing
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 insufficient chlorine.
A - Acid gases containing about 10 to 12 percent HCl with equilibrium vapor have
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 After testing ore samples (with intact reactivity) at various temperatures and for different times, the following results were obtained:
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<tb> Time <SEP> 3 <SEP> hours <SEP> 44 <SEP> hours <SEP>
<tb>
 
 EMI22.8
 mid -e a5 degrees? 25 degrees
 EMI22.9
 
<tb>% <SEP> of <SEP> nickel <SEP> soluble <SEP> 52 <SEP> 54
<tb>
 
 EMI22.10
 m - Similar op2'ra-I.-ions were made still a., very with? 0 volumes for acid, with the 8, liva .It:

   
 EMI22.11
 
<tb> Time <SEP> 4 <SEP> hours <SEP> 20 <SEP> hours
<tb>
<tb> Temperature <SEP> 190-300 <SEP> C <SEP> lgo-2000 <SEP> 0
<tb>
<tb> of <SEP> nickel <SEP> soluble <SEP> 44 <SEP> 64
<tb>
 

 <Desc / Clms Page number 23>

 
If the gases are not strong enough to chlorinate nickel in a few hours satisfactorily, chlorination carried out continuously with gases of the same strength will not improve the results immeasurably. load-bearing, in the temperature scale where the attack is differential satisfactorily, as between nickel and iron.



   Chlorination below about 190 degrees.



   Chlorumination at temperatures substantially below 190 degrees + end to excessive iron attack; the differential character of the chlorinating effect of the HCL-H2O vapor mixtures gradually decreases as the temperature decreases, being lost, finally under the essentially non-differential effect of the aqueous HCL solutions.

   This observation applies particularly to the ratios of HCL-H2O capable of producing good nickel solubilitiesa and with the times required to obtain this result, the loss of the differential effect is somewhat diminished by the presence of large amounts of nickel. other gases than HCL and H20, for example nitrogen, in one case, in one hour and 30 minutes, in a reactor tube maintained at a temperature of 135 degrees, 28 percent by volume of HCL n ' produced, that 57.9 of the solubility of the nickel alks that 53.4 of the iron present was chlorinated more than undesirable result. The pieces of ore had become wet.



   Prolonged treatment (20 hours) with 14 volume percent HO1 in a reactor tube maintained at 180 degrees gave only 72.6% nickel solubility, and 52% nickel solubility. The pieces of ore were getting wet, although it had only been processed for 12 hours.

 <Desc / Clms Page number 24>

 
 EMI24.1
 



  In the temperature scale below about 190, continued chlorination with o-az d.'H01 -! Fa last / as a result gave water condensation, and in such quantity that the pieces The ore became soft and pasty, consisting of a spongy ore residue impregnated with saturated ferric chloride solution. Operations producing this result do not
 EMI24.2
 are not recommended.9 and are not to be classified under the term "in the dry manner". Rapid chlorination below 100, with rapid rise in mid-temperature.
 EMI24.3
 ne = a, 1, is sometimes cepddari- dsian1ep.

   For example, 8.'1] '' '' '0:' np. chlorura + ion of medium rapidity, the ore dried to 91-oo and cooled, for example during the journey to ra.ctev¯r, to about 160-1? 0, will rapidly increase in temperature up to below 190, thanks to the heat of reaction and the heat of the gas stream, etc.



   With ore whose reactivity of the nickel content has been reduced by too long heating, or has
 EMI24.4
 + -r-piratures high, or pa7- natural causes, such as metamorphic effects, so that we have obtained "'in: Element9 not satisfying by the metals. most popular methods, we often obtain good
 EMI24.5
 In addition, the chlorination of the :: 6 = below the oipéndaflt for a long time is co-enforced and continued. The chlorination of the iron is then more intense than by the preferred method.
 EMI24.6
 a fi'e case; employing 52 percent HCl and an externally heated reagent by steam, and treating the material with combined water reduced to 3.8%, a nickel solubility of 3.8% was obtained. 96.2%.

   The ore
 EMI24.7
 chloride contained 19 FeOCl. 30 da iron was chlorinated. In other cases, we have obtained solubilities of

 <Desc / Clms Page number 25>

 86-93% nickel with 15-20% of chlorinated iron. The operations which have just been described are expensive and it is advisable not to carry them out except for the slowly reactive ores of nickel, as they are extracted.



   Effects on the heating of completely or partially chlorinated ore, and on the heating during chlorination,
When the chlorinated ore at 190-2100 C., for example is subsequently heated, in the absence of any gas coming from the outside, the combined water which is gradually degane reacts with the aluminum chlorides and iron (little appreciably with ferrous chloride or nickel chloride), and produces HCL.

   In one case, heating the ore would hydrolyze to about 210, and gases containing more than 60 volume percent HO1 were vented during the temperature rise from 220 to 230 (in the process consisting of; heating at higher temperatures). These gases are of an undesirable force for this temperature; they produce FeOCl and increase the production of ferrous chloride, which is not beneficial.



    In one case, on heating up to 250, ferrous iron in the chloride form increased from 0.64% to 1.16%; in another case, on heating up to 300 the ferrous iron in the form of chloride increased from 0.84 to 4.40% - most undesirable result; in both cases, the amount of FeOCI in the ore was more than doubled.



   It is important, when the temperature of the partially or totally chlorinated ore rises, to be able to control this effect. As we have seen (example 4), this is done by supplying az HCL- H2O which dilutes the gases drying pieces of ore to the desired concentration,

 <Desc / Clms Page number 26>

 or even below, which restores the concentration by stronger gases from outside.

   This last process protects
 EMI26.1
 cn.J..rlO 'superchlorination - unnecessarily increasing the amounts - iron chloride during the rise of' f'Pl ?? r6 '!' 'are, it is usually preferred to operate in this way; aciQvan- the chlorination of nickel before raising the temperature (except the natural rise during chlorination; rr / Éce auz heats of reaction, a few rapid degrees,
 EMI26.2
 sou1T "! nt \. nn can, however, use the effect which is in
 EMI26.3
 globs + 9ncb the concentration of Xi. One then treats, at 190- ln deqr4s, for example, with az giving rather the lowest yields desired, namely 23-25 volumes for csnt.;: 'PCI and nickel solubilities, for an ore particular, about 88-90.

   The temperature is then raised by passing limited quantities of ilus gases derived from the last phase of hydrolysis or destruction of? chloride so that as the temperature rises
 EMI26.4
 the minerei Psi en70uré of stronger gases, coming from the mixture of the HCL which occurs by itself with the diluted gases, In this ++ = way we increased the percentage of the
 EMI26.5
 90hilit of n-lok? L until 97-98. The operation requires very serious control to avoid the increase of ferrous chloride and FeOCl; when either of these appears to be detrimentally increased, the flow of dilution gases is increased.

   With large pieces, especially with a rapid rise in temperature, either by the heat of reaction or by external heating, strong HOI gases can be produced inside the pieces and superchlorinate the piece. ore before the gases produced can be diluted to the desired strength by the gases flowing around the pieces.

 <Desc / Clms Page number 27>

 This effect can be controlled by employing smaller pieces, increasing the speed of the gases, and slowing the rise in temperature. It will be understood that the effect can be used in conjunction with a slow and continuous temperature rise during the chlorination.



   Temperatures during the chlorination process.



   As we have seen, the chlorination of nickel often takes place entirely and always in part above temperatures around 1900. The lower limit is set by the excessive formation of chlorides other than that of nickel and by the last humidification of the ore at the lowest temperatures. The upper limit of operations is usually fixed, partly by the fundamental properties of the chlorides of iron, Fecl3 and FeOG1, and partly by the kind of the particular ore involved. At about 290-310 degrees 0, and above, nickel, in most ores, loses the ability to react with HCL of desirable strength, quickly enough to interfere with operations.

   High solubilities and high yields thus cramped the use of very strong HCL gases, difficult to recover from washing solutions, and the use of these strong gases results in excessive attack of the iron. Excessive iron attack is caused at these temperatures by the volatilization of FeCL3 and even FeOCl in the strong HCL gas stream. This invention does not relate to the operation with high volatilization of the iron content of the ore.
Some ores lose the reactivity of nickel when they stay hot much faster than others; this characteristic is easily detected by a simple test.

   Minerals of extreme heat sensitivity must ordinarily be chlorinated at 190-210

 <Desc / Clms Page number 28>

 
 EMI28.1
 -or-sai-le -1-oil-jo-urs below 235 or 225.



  Precautions to. Aim to destroy lTi (1l-2¯.! ¯f¯2 - 'izing FeC12. Etc ..- In order to c' = 'avoid destroying Niol 2 by the reaction NiCla H2 = Nio 4- 2HOL i '-s4- r-ces8aire that the vareur or gases H 0 - H01 which -lilute in HC1 used to destroy FeC131 etc. .., contain at least the minimum quantities of H01. -4¯The minimum required feels higher when the temperature is higher, and feels somewhat variable following
 EMI28.2
 minerals.

   Around 275 C., for
 EMI28.3
 the "ai.7r": in "'s very fast, a vol'me percent HOl in -, rower if often. for pro: 5er Ni012 'although it is, usually more prudent to use 5 to 10% when other gases than HO1 and H0 are present, pEI. "e7er ..- ole of C12 or oxygen , to participate in the ies + Tuction of FeCl2 (and when oxygen is used, or air has it), the proteetian effect of X61 on NiOl 2 is? iruuated, and one em-, oloyer in proportion more Hol than 1a. '! "E; U1'.



  Nickel chloride is also susceptible - '! The effect is usual with oxygen. The effect is usual at around 275-Zo0, but becomes protracted at high temperatures. It can be protected against this + effef by the rz, -4ser-ce e small quantities of 012-
 EMI28.4
 It is possible to heat the chlorurà ore
 EMI28.5
 of excess. those given in the examples
 EMI28.6
 above. When taking greater precautions
 EMI28.7
 must "be pl> ise6 to avoid the destruction of the chloride
 EMI28.8
 nickel. If we pass air over the ore to
 EMI28.9
 high tefup9xas, elemental chlorine, 01 2 'must

 <Desc / Clms Page number 29>

 ê + re present to protect nickel chloride from oxy- da + in. Cobalt requires even more chlorine to prevent oxidation of its chloride.

   If, as we usually do, we want to recover the cobalt, and we use oxygen (air), we should use 012 even around 300.



   The cost of the operation is significantly increased by the use of + empéra + ureélvées. and it is better to dp avoid them. It is very rarely justified to operate at temperatures higher than 350, and most often the phase of destruction of the chloride is carried out well below 300.



     Use of oxidizing agents during the chlorination operation.



   Oxidation agents - CL2, or oxygen (air) - may be kept present and be somewhat active during the chlorination process, distinct from a recent FeCL2 destruction operation. There is no small advantage - if there is one - in doing so. If the CL2 is used, the cost of the device is increased.



  Oxygen is most effective at elevated temperatures, suitable for the rapid destruction, by HCO vapor sufficiently diluted in HCl, of all FeCL3 - best well above 250 C., as is indicated.



   Additional notes on the destruction of WeCl2.



   ----------------------- As indicated, FeCL3, ALOCL3 and FeOCL can still be destroyed, without damaging NiCL2, by increasing the H2O and reducing the concentration of H01 - for commercial stiffness best at 250-275 C. Ferrous chloride requires an oxidizing agent as well. Oxygen has advantages over chlorine,

 <Desc / Clms Page number 30>

 
 EMI30.1
 s- "c''3. '' r? n at temperatures above the raacticn of the nacon method, does not occur, in that it allows the em- j of -eao + them entirely in iron; with the 012 $ the p + "fIPS exposed to Cl 3 are preferably made of a ferrous alloy of chromium and nickel.

   But, with oxygen, we must take into account the influence of residual nitrogen by reducing the activity of H01 by increasing the activity of
 EMI30.2
 H'0, cor.-.- we have it d4c1 + on the other hand. To avoid this, sometimes we destroy almost all of the Fecl, AlCL3, and FeOC at first, then, we then process in a stream.
 EMI30.3
 gas separated with air and HGl - H4 gas diluted dpns Hcl to destroy Fe012 'by passing the gases through this phase around the main areas of obloruisa4-.irn, eleva- ticn d- temperature and hydrolysis, and st adding these gases to the main stream when decent lower in HCL.



   Effect of pressure, vacuum and other gases
 EMI30.4
 that FC1 Ft of the water vereu--.



  In most cases the operation is recommended
 EMI30.5
 Atmospheric nressirn. Superatmospheric pressures can be used, but the expense is reduced. When operating at superatosT '\ l' preassion:. 4iQ.ue; the relative activity of H01 gas is greater e + that of gas X 2 o is less than e under atmospheric pressure Likewise, the operation can be carried out at reduced pressure, but this is also seldom to be desired.



  At reduced pressure, the effect of removing the H2O gas is reduced.
 EMI30.6
 lativerer-1- av: erté, and the chlorinating power of HCl is ra1 @ tive! '. <1ent decreased. At pressures above or below atmospheric pressure, changes in the activity of the two agents can be easily controlled.

 <Desc / Clms Page number 31>

 



   The present gases other than the two essential ones simulate the effe of reduction of the total pressure. This case is often encountered in practice. When large amounts of gases other than HCL and H2O are present, for example N2.00 2 (more rarely O2, CL2), the ratio of HCL to H2O must be adjusted. It must have more HCL gas in its proprtion compared to H2O gas. A good general rule of thumb for pre-tuning is that the square of the percentage by volume of HCL gas in the diluted mixture, divided by the percentage by volume of H2O gas in the diluted mixture should be squared of the percentage by volume of GAZX hcl in a mixture satisfy UNDILUTED DIVIDED by the volume percentage of H2O gas in that undiluted mixture.

   We often need more HCL. This caloul is seldom necessary; it is usually sufficient when changing from pure gases to dilute gases, to increase HCL and decrease R 0 slowly until the results are obtained.
2 satisfactory conditions. One must also guard against high dilution with H2, CO2, etc., and consider as an important feature of the invention the possibility it offers to render this dilution unnecessary.



   Gas force adjustment - replacement of HCL
Hydrochloric acid gas, produced by any known means, and used for waste replacement is generally too strong to be used without dilution.



  Gases containing hydrochloric acid recovered from the calcination of nickel chloride, etc., are also often too strong. It will be understood that steam, or steam containing HCl gas, is always available in the process of diluting these feed gases at the appropriate strength.

 <Desc / Clms Page number 32>

 
 EMI32.1
 



  Fn performing the chlorination phase at any + e; n4a + ure palicuiiére, or in a temperature scale
 EMI32.2
 Res particulars or advises to start with gases of a
 EMI32.3
 However, this will be somewhat less than what is believed to be necessary for the desired yields. For example,? Or at a 7C '! T'mes percent of HOl at 190-210 0., or 35 40 volumes for cen + of HCI 4x around 250 (the balance of Mez state-t of H 2 0 ), and then, when the ore
 EMI32.4
 chloride passes and can be analyzed, we increase slowly
 EMI32.5
 l7se in the FC1 content of gases. from time to time, which / does
 EMI32.6
 easily, for example, by reducing the return of diluted gases coming from more distant points on the path of discharge of the chlorination gases.

   In this way, with a
 EMI32.7
 particular mirerai, apparatus, drying conditions,
 EMI32.8
 at rates of az, etc., the optimum az concentrations are easily controlled and the desired yields of rickel obtained with maximum differential chlorination eifet, that is,; .ire -a minimum chloruraticn of iron.



  Resistance of the pieces to the deactivation effect of water, af9c "not the maximum temperature and the presence of iron chlcrures. Romm; or '¯' in chlorinated mo-waters in the surroundings" "0 to '7", or treated at or above these temperatures or above. OhlorursLticn does not inconvenience 1: 1.'. 1 wash, reg = orcels of chlorinated ore at 190-210 se d / qan + 4-, usually washing and, if it is desired to obtain the benefits of the laaqe by filtration and the production of little friB in strong solutions, then the pieces must be heated to high temperatures.

   Mor-
 EMI32.9
 These r ^ a'Suits from 110 to 2350 are so sensitive to water, fh particularly if we have obtained a very j-s01Uability of the

 <Desc / Clms Page number 33>

 nickel, for example by using somewhat higher HCl forces than necessary. The chlorinated pieces can still be made resistant to washing by the treatments described; that is, by raising the temperature and (or else) destroying the foreign chlorides.



   Drying times and temperatures - Possibility of varying ores.



   With the ores treated in the examples given, the damage caused to reactivity by the stay in heat was zero at 150 ° C., negligible around 200-225, slow at around 250. and very fast around 300-325. The damage is rapid around 225 with all the ores that have been tested, but the temperature at which the loss of reactivity begins with the stay in heat is variable. never found it low enough to interfere with drying for the 190-225 treatment? In some cases it is excessively slow at 250. The safe temperature can easily be found for each ore.

   During the operation, it is good to make the drying time as short as possible, and to raise the maximum temperature by? drying gas from time to time, until the nickel solubility decreasing beyond the desired point gives an alarm. It is usually preferable to reduce the maximum temperature of the drying gases by a few degrees and then to stabilize them. The costs of drying and heat consumption are saved by drying at the highest temperature compatible with the desired yields.



   It is generally desirable to entrain, in addition to the hygroscoic water, as much combined water as possible without decreasing the differential reactivity to nickel under the particular operating conditions. With an installation

 <Desc / Clms Page number 34>

 in stationary operation, giving satisfactory nickel yields, it is often desirable to increase the quantity of combined water to be carried away by small quantities; until the nickel yield begins to decrease, usually by increasing the drying temperature, and better, if gold can have greater drying capacity, by increasing the drying time and increasing the depth ore bed onto the belt or dryer grid and increase its speed.
 EMI34.1
 



  "'ores containing calamum carbonates and 2: 6 mao'nesium? Most lateritic ores do not contain traces of this calamum and magnesium in the form of carbonates or in any other form. Some ores are
 EMI34.2
 in +? tmédiairé6 between laterites and garnierites, or nickel silicate ores common to New Caledonia
 EMI34.3
 donie. These marniérites usually contain a lot of calcium and magnesium as carbonates, or under other ferras - :? i1en: en 'attacked by hydrochloric adide in the process of operation p - steps for the setting. The full advantages of this invention np 5T '' * 'are realized with such ores; unless decomposing, by known means, the calcium chlorides and ": e - rrrrnssiun.



  Kirerpis approaching the garnierite type are often very dense and non-porous and require fine grinding. Furthermore, these ores are often so rich in nickel that it is more profitable to process them by known direct smelting methods rather than by the present process.

 <Desc / Clms Page number 35>

 



   Treatment of washing solutions.¯.



   An overview has been given of the preparation of solid nickel solutions free of any iron, aluminum and cobalt, as well as of any products composing the precipitating agents employed in the conventional separation and precipitation of the metals contained, such as chloride of sodimor calcium chloride, and the nickel oxide production of these solutions was shown without the use of chemicals, and with recovery of the HCL and H2O gas mixtures ready for reuse.



   The niokel solutions can be worked in other ways, for example preparing nickel sulfate for electroplating. To do this, nickel chloride is crystallized from the strong solution and the orixteaux are treated with sulfuric acid, entraining the HXL and H 0 gases of appropriate strength for use in the chlorination. 2 When the ore is low in cobalt or when the presence of cobalt in the nickel product allows it, the iron and aluminum can be separated only from the original wash solution.

   In doing so, the iron is first oxidized in the solution of the erric state, and it is then precipitated with carbonate or nickel hydroxide prepared from de-washing liquors, or from a part. the main solution,
Lateritic iron ores often contain up to 500 grams of manganese for 1,500 grams of nickel and most of this manganese will follow the nickel in the process. Manganese can be separated from nickel by known methods.



   The preferred methods are particularly advantageous in that they avoid the need to introduce sulfur in any form at any time.

 <Desc / Clms Page number 36>

 
 EMI36.1
 , a l ', n3-.alin, and rerr.:eten- thus to' break in nickel and nickel alloys freed from all impurities without using, ¯, special considerations for this + 4.th elimination, 'Ventilation. for example, when preparing sensitive solutions
 EMI36.2
 sibleB'n- free of iron, and to destroy desired iznr chlorides at around? 75, the chlorinated ore is ventilated to admit HCl.

   This is important, but is heavoeoup at high temperatures during the destruction operation, chlorides; we keep less and less
 EMI36.3
 This is Ia'f 1 in the ore as the temperature rises. countercurrent nnératien potant on the economy 1 PUI.



  It is considered of the greatest importance to discover
 EMI36.4
 / t3i + / ±, f .re = "e fite that, while the ^ az of a certain maximum force rU \ '" ma are n'cess.ires at a given temperature to perform a high percentage nickel chloruratlen%, we can ao- complete the work with all forcing less gas,
 EMI36.5
 e-1- t: QPLY'aT.? 'f' also important the provisions of the reversal for 1- treatment of chlorination first with dëo it is very much done -in vcred, of simple steam - , then sucks6ivern + with increasingly strong gases up to the maximum jU1t necessary for the particular conditions o-yt.trai, ¯raa- azdE88tt7.8 of 20-25 percent volumes, even at 100-310 C., rareKen above 60 percent volume, even around 250-2700.



  Because of the return of supply of the diluted gases used in the chloride destruction phase, and (or else) in the dilution of excessively strong or recovered HCl produced, the chlorination operation may not be
 EMI36.6
 srict .r. ^ nt to c0nDOoat, but it is considered possible to define it by this term.

 <Desc / Clms Page number 37>

 



   Also considered very important are the arrangements required to allow perfect gas-solid contact in the backflow, and hence the effective exposure of the minus with each gas force progressively increasing.



   It is easily understood how the fixed reactors are interconnected for gas flow, and that the gas connections are changed from time to time, so that the countercurrent burst conditions are obtained although the ore either fixed. The same comments apply to the interconnections and fluid flow between the wash tanks.



   The words "to bring the ore into permeable pieces" which feel employed allude to simple operations of sifting, or of grinding and sifting, which can be applied to clumped ore, for example, by natural actions, such as cooking auccolsil, provided that the clumped ore is permeable.



   The term "drying" as employed tends to include the preliminary heating which is necessary to bring the ore to its initial chlorination temperature. This preliminary heating is usually a by-product of the drying process. In hot climates, the ore dried at the surface by the sun may hardly need to be dried, being almost free of all moisture. In this case, the operation called "drying. ", immediately preceding the chlorination phase, can be used as preliminary heating.


    

Claims (1)

EMI38.1 CLAIMS EMI38.2 -: -: -: -: -: -: -: 1.- Process of krai'-ement of laterite ores for the tµcu-oã: 1; n of the nickel values contained therein EMI38.3 naked; including almost dry nickel chlorination EMI38.4 with u '1 caoex as essential chlorinating agent and EMI38.5 EMI38.6 H 0 gas coms'e arnen'- essential retention; in relative concentrations controlled with respect to the temperature of the chlorination and then the separation of the nickel chloride from the mine. 2.- In a process as claimed in 1, the r4j, j: inn d. "Ore in pieces of permeable dimension; aTrar chlo-uration, and the chlorination of one or more pacti-s of these pieces; the o -az being sent systematically to, through the interstices of this or these parts of theomorneaux. : 3.- In -, n process as claimed in 1 or 2; the 3ec'zarne 1 miner-i and its routing to the tempera- - &, o8 ^ The cMc-uration while the natural reactivity of nickel is maintained substantially the same, thanks to the con- EMI38.7 control of drying time and drying temperatures. EMI38.8 4.- In a process as claimed in en7., 2; and; nickel chlorqol at temperatures below about 70%, and at least most of the time; aU-d? '9SUS? A lQt "I-1QO C. ¯ parts of the process such as stink claimed in 1; 2, p- 4, 1. at least partial destruction of the chlorides in- i, 1, - qes fe es during the chlorination by treating it .eut u1 "'.: 2'" i '? "Cr dry while protecting the NiÙL2. 6.- nana a pocé3é as read claimed in 5, the acOi3seen.L 0 t-aiterent following at temperatures, at EMI38.9 me # s èi11ehent, above? 40-250 C. <Desc / Clms Page number 39> 7. - In a method according to one of claims 1 to 6, the. separating nickel chloride from ore by washing; 8.- In a process as claimed in 7, the center-current washing to produce strong solutions; 9.- In a process as claimed in 7 or 8, working the solutions for the metal values; 10. - In a process as claimed in 8, the working of the solutions for the values of metal in the form of oxides and for the gavs containing HCL and steam for the regmploi by evaporation of the solution and the caloination of the chlorides in presence of H2O. 11. In a process as claimed in 2, the passage of the chlorination gases in countercurrent through a layer or a series of layers of pieces of ore of the same size; 12.- Dmma process as claimed in 7 or 8, the purification of the solution of one or more of the metaixes cobalt, iron and aluminum, thanks to precipitating agents containing nickel or nickel hydroxide or carbonate of nickel and substantially free of alkali or alkaline earth hydroxide or carbonate and the recovery of the nickel chloride crystals from the purified solution. 13. - In a process as claimed in 12, the preparation of oxides of nickel and gas containing HCL and steam nour the re-use by calcining nickel chloride. 14.- In a. method as claimed in 7 or 8, ventilating the hot chlorinated ore before washing. <Desc / Clms Page number 40> EMI40.1 A F Q E 15 E Perfcionnen + 6 to the treatment processes; latetitic ore6.