LU82081A1 - NATURAL CALCIUM PHOSPHATE DEFLUORINATED FOR ANIMAL FEEDING - Google Patents

Description

f] j | ...................... 7 ........... '·' f jί. The present invention relates to a new quality • {} of phoc; defluorinated calcium phate for animal feed and | J its preparation process.

j j Le9 defluorinated calcium phosphates are I t, · .15 important industrial products used as food supplements | 1 | animal or as important constituents of these supplements. : j · •! | alongside nitrogen derivatives, sugars, trace elements and j j vitamins ...

• j · A first technique for preparing the phosphate of; 1P j defluorinated calcium which has been used for a long time by demand- * · resso consists in neutralizing a defluorinated phosphoric acid, • {! '' that is to say either a phosphoric acid obtained thermally or a purified wet acid, by a calcium compound such as lime, calcium carbonate, calcium chloride j finely ground. The product obtained which is a mixture of phosphates • | j} bicalcique and monocalcique is practically colorless, it con-! : is good for animal feed but it has the serious disadvantage of being of a high cost price.

i j j Another 9 phosphates preparation technique! , 2 (j J defluorinated calcium consists in thermally treating a natural phosphate || in the presence generally of adjuvants necessary to facilitate • J cilitate defluorination and obtain a product assimilable by i! *; * · * Animals * • · 1 The phosphates obtained according to this technique have the commercial disadvantage of being strongly colored and therefore the manufacturers of animal feed supplements recommend them.

I throw in favor of phosphates prepared by the wet process.

j In addition, thermal defluorinated phosphates ac-! So many on the market do not simultaneously have all of the characteristics of wet phosphates.

There was therefore a need for a defluorinated natural calcium phosphate usable for animal feed in the same way as the wet calcium phosphates,

The Applicant in the context of its studies on 3f calcium phosphate has developed a quality of phosphate of! thermal calcium which responds - particularly well to,] 1 [............................ '· I: I requirements of the animolo food. Cotto quality of calcium phor is characterized by the following properties! ! j P total 15 to 21 by weight I! F <0.2% "; 5 · Ca 25% i | Na 6 - 10% ‘i! ; As <10 ppm I * j ^ crystalline phase Na ^ Ca ^ (P0 ^) ^^> 70 $ | crystalline phase apatite <1 i * | iq j crystalline phase Ca ^ {PO ^) ^ ß ^ $ r · · ♦ î, *! citric solubility 90%

In order to prepare these phosphates, the applicant has developed a process which has the advantage, over known techniques, of being able to use as raw material all 2 15 'natural calcium phosphates currently available, even "J J' I] · less rich in P 0_ such Algerian phosphates which tit dd $ 28.5 in P ^ O ^., and this leads to an excellent thermal balance j | corresponding to consumption of heavy fuel oil n ° 2 of e || B0 to 100 kg per ton of defluorinated phosphate obtained, then i '.

I 20 the methods known to the applicant it is common to c I j; 2 to 4 times more fuel.

he.,-, ! 1 One of the special advantages of this technique! ” to be able to use, in the same way, phosphates poor in silica-rich content, whereas in previous processes r r: I "; 25. posed it was indicated as essential either of use ("i | rai of SiO content greater than 2.5% by weight (LJJ patent that 902 361) r or to use an ore of SiO2 content higher than Z 5" by weight (BF 2 026 B7B).

; „The process claimed is a process by t 3 £ which can in practice only be carried out continuously and comprises the following 14 steps: preliminary attack, nation conditioning, quenching.

1 - The preliminary attack of the ore is carried out by adding to the latter first of all phosphori acid i nuis anres a reaction reaction time è-5 minutes ac '· 3.

.............-................ ~ ........ -. .......... κ, · "" soda and fines recycled; these latter reagents being introduced in an amount such that in the final product the 1 molar CaO / Na 2 O / P 0 ratios are between 7.6 / 1 / 2.9 and 3.6 / 1 / 1.5.

'5. The ore used must be of a particle size such that the reaction of the phosphoric acid on the ore is sufficient. Generally we start with an ore with a mean diameter of 150 microns. The attack can be carried out in any suitable mixer, such as conventional phosphoric acid attack tanks placed in series and mixers with horizontal arms, the phosphoric acid is preferably one acid per channel; humid titrating from 25 to 55 $ in this ac ^ e Ρευ * be used cold or at 50 - 6D ° C if it is prepared in a neighboring workshop which reduces the attack time, • 1 i Sodium reagents are introduced after a time of at least 5 minutes of variable phosphoric attack depending on the minor and the apparatus used. Sodium carbonate or sodium hydroxide are preferably used but it is possible to use any other sodium salt such as sulfate, nitrate, chloride ’,, 23 phosphate; the mixing is continued until satisfactory homogenization of the treated mass. ! 2 - The conditioning is carried out at a drying temperature i greater than 1D0 ° C by the fumes · from calcination in 1 form of granules of dimensions between 0.5 and 5 mm. The ; , 25 'conditioning device is different depending on whether you use a solid sodium reagent, such as sodium carbonate or liquid! such as sodium hydroxide solutions. ! •

When using a solid sodium reagent:

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The homogenized mixture according to 1 is introduced into a lump breaker followed by a sieve separating the large particles which are returned to the inlet of the lump breaker from the others which are directed to a dryer. All the drying means which do not cause the destruction of the granules can be used, in particular a rotary oven or a tunnel oven heated by gases originating from calcination can be used, where the temperature of the product is raised above 100 ° C. . The dried product is sieved to I. _____________________________________________ ___________ .... ......

CT '♦ * · · · GÖparcr len fractions less than 0.5 mm which are returned or I point of introduction of the soda derivative during the preliminary attack i,, 1 st of the ore, and particles larger than 5 mrrTqui are returned to the lump breaker, the product with a size of between 0.5 5i and 5 mm being sent to the calcination preheater, i In the case of the addition of a liquid sodium reagent the * "slurry leaving the attack preliminary is sent directly to a drying granulator. Le9 granules formed brought to a time | * peraturc at least 100 ° C are sieved, the fines are recycled! · I i1D at the entrance of the granulator, the large ones are returned to the attack

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j; ; preliminary and particles between 0.5 and 5 mm are

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"T, | directed to the calcination preheater.

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3 - The calcination which must be carried out between 1 10C and 1 300 ° C and preferably between 1 160 and 1 250 ° C is preceded H 15 by a preheating stage where .the particles introduced are * | ,! brought to around 7D0 ° C by the hot gases leaving the calcinBtcui II! fj | The calcination can be carried out in a fluidized bed or in a rotary kiln.

j In the step of using a fluidized bed preheating. S ge ‘and calcination at 1150 ° C - 1250 ° C are carried out in two>; I w Ü * Ϊ20ί ‘separate appliances whereas in the case of the use of an oven j» | »Turning only one device is used preheating done | in the coldest part of the rotary kiln. Outgoing gases •! i - from the preheater are used for conditioning phase 2 "! j and the combustion air is preheated during the final quenching 25. by cooling the calcined product.

: · '· 1 day! ; j It is generally preferable to carry out calcine- I- * ", tion as is known in the presence of water vapor. If the calcination is carried out using an oil burner an addition of 10 is carried out. at 20% water vapor by volume in the gas mixture obtained, if the calcination is carried out with a gas burner, the water vapor obtained by combustion of the gas is sufficient 4 - The quenching must allow the fastest cooling : dement possible and in any case in less than two minutes the product calcined. Preferably quenching is carried out with cold air I 35 under conditions such that in less than 2 minutes the temperature of the product leaving the calciner is brought back from L .5!! -.; i! 1150 ° C to 1250 ° C at less than 800 ° C. The techniques of fluid bed 'I, se or vibrating bed are particularly suitable for realizing | such tempering. A cold air belt cooler by: ji

I example or in a fluidized bed brings the defluorinated phosphate obtained to I

j 5 at room temperature, the calories recovered at this stage can | j! be used for example to supply a boiler or be used for drying stage 2.

i: I The defluorinated phosphates prepared according to this process 'j' having all the properties indicated above allow- I | J 1Çj try to meet the various requirements of users, te-; .! The respective values of the various crystalline phases are in particular essential for obtaining products giving full satisfaction in animal nutrition, j, ·, i

Many devices are likely to allow. to obtain defluorinated phosphate according to the claimed process, i i! The attached figure illustrates a diagram implemented in a manner that *! j i l: satisfactory by the plaintiff, ί | j The ore and phosphoric acid are introduced res— I e

j | pectively by conduits 1 and 2 in the first part I

2Û: a horizontal mixer with double vi9 I-XI; In the 2nd part | II from this mixer arrives at 3, the necessary sodium reagent and at day 4 the fines from the VI or XIII sieves are recycled, In? | i - in the case of the use of a solid sodium reagent the mixture obtained is j 1 sent to the lump breaker III followed by a sieve IV through the pipes! , 25 5 and 6, then to a dryer V and to a sieve VI through B and 9, the fi-;

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; j · born from VI are returned to II by 4 and the large ones to III pax j * S * 22 and 7 · In the case of the use of a liquid sodium reagent the melan-j

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ge obtained is sent by 23 to the dryer granulator XII "then.

m by 24 with a XIII sieve, the ends and ends of which are returned 3) born in II by 26 and 4, The granules leaving VI or XIII feed the preheating of the calcination by 1D and 25, The preheater VII is followed by 'a calciner VIII supplied with hot air by 12 with fuel by 13 and possibly with water vapor by 14. The calcined product arrives in the trem-3 device!> pe IX by 11 or it is cooled by cold air coming in! 15, then by 16 in an X cooler using aii 6 ’! ---------------------------------------------- * · · · '- *! .

: '· (Introduced cold in 18 and leave by 27 · The defluorinated phosphate obtained leaves cold by 17 "| To perfect the recovery of calories the air comes out.

j while in 19 the preheater supplies for example the dryer V

j 5 j as shown (or the dryer granulator XII), the fumes | | cooled are evacuated by 2D to an XI scrubber washer with i · j to be evacuated to the atmosphere by 21.

The examples below illustrate, but are not limited to, the defluorinated calcium phosphate claimed by the applicant and its manufacturing process as described; j: | i previously and is shown diagrammatically in the attached figure, j 1 EXAMPLE 1

The mixer I is fed by 1 with 100 parts per hour by weight of a Togo phosphate of average diameter 150 μ 35 grading 36.5% of PO, 4.15 ^ of F and $ 51 of CaO. By 2 on t w! adds 52 parts an hour of PO H at 35% P O then, by 3, i 4 3 Z j | ’25 parts an hour of sodium carbonate. The mixture coming out in! j 5 is lumped in IIIt sieved in IV to a dimension less than j 5 mm, dried in V è 120 ° C and re-screened in VI to remove the fine and coarse I · 20 * · formed on drying. The granule obtained is j d preheated and then calcined in 2 hours in a rotary oven VII - J VIII where its temperature goes from 120 ° C to 1240 ° C, the fumes going out to 550 ° C. The outgoing product is soaked at 6D0 ° C in a fluidized i · # IX bed and then cooled to room temperature in X.

25 Taking into account the recycling carried out as indicated above, 127 parts an hour of a defluorinated phosphate i are obtained! having the following characteristics ï I! P total £ 18.45 F 0.02% · d30 Ca 29.5%.

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Na 7.8 / ¾ \. ; j As B ppm crystalline phase Na Ca. (P0) 95% | 3 q 4 5 crystalline phase apatite not detected 35 crystalline phase Ca ^ (PO ^) ^ β not detected citric solubility '96 5 = i / - ù .......

EXEKPl E 2

The mixer I is supplied with 100 parts of the same phosphate phosphate from Togo as in example 1, 45.5 parts of PO ^ H ^ | 35% P 0 and 20 parts of CO Na. The treatment is effective! 2 5 r .32 l 5 killed exactly as in example 1 and we obtain 122 part * I}. .

i of a defluorinated phosphate suitable for pre-animal feed. I i I} have the following characteristics:! ’P total 18.0 d’ F 0.18 i, 10 d Ca 29.8% \ Na 6.2%

As 8 ppm crystalline phase Na Ca (PO.) 90% 2 6 4 5 ^ crystalline phase apatite undetected 15 crystalline phase Ca ^ (PQ ^ Îg P 2%! Citric solubility 92 5 "!: EXAMPLE 3 • * j This example is carried out with the Mfèroe phosphate of Toc I and under the same conditions as in Example 1 except as regards • * I * 20; relates to preheating and calcination; preheating is carried out in cyclone from 120®C to 7D0 ° C followed immediately by * * I calcination in a fluidized bed at 1220 ° C. The defluorinated phosphate 'I ·' obtained has substantially the same characteristics as that of the product prepared in Example 1.

. ' ’25 EXAMPLE 4 •: We treat under the conditions of example 1 î j i j i | 100 parts per hour of a Moroccan titanium phosphate ore. ! i 32.3 ^ in PO, $ 4 in F and 51.9% in CaD by 63.5 parts / hit • 2 5 of PO H at 35% from P 0 and 25 parts / hr of CD Na · | 4 3 2 5 3 2 30 We obtain 129 particles / hour of a phosphate having the following characteristics: P total 18.3 $ F 0.06 £

Co 29.5% 35 Na 6.9% “f” · 1

As 6 ppm! Na_Ca, crystalline phase. (PO) 94% J b 4 5 crystalline phase apatite not detected! crystalline phase Ca (PO) ß 3% • 3 4 2! "_ J citric solubility 94 * $> - i S! EXAMPLE 5 '! î} *: js This example is carried out with the same phosphate maro-) j cein and under the same conditions as lf example 4 except with regard to preheating and calcination where instead of a rotary oven a preheating in cyclone is carried out from 120 ° C to 700 ° C! 1 u; immediately followed by calcination at 1222 ° C.

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The defluorinated phosphate obtained has the characteristics

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{following ticks: P total 18.5%; F 0.12% * 1S | Ca 29.5% it 'Na £ 6.9! ; j j As 6 ppm $ i. crystalline phase Na Ca (PO) 90 ί I 3 6 4 5 fcj »j | undetected apatite crystal phase · 'Mi • 23! crystalline phase Ca_ (PO î ß 4 $! j 3 4 2! citric solubility 9D $ • 'This example is carried out with the same maroca phosphate.

, and under the same conditions as in example 4 but using • 25: B2.3 parts / hour of PO H at 2? ^ from P 0 and 3B parts / hour - ·! |! - 4 3 2 5 d d of 50% aqueous sodium hydroxide solution, •

129 parts of a fluorinated phosphate are obtained which; ·; has the same characteristics as in example 4.

EXAMPLE 7 3D This example is carried out with the same maroca phosphate and under the same conditions as Example 4 but using 15 parts of PO ^ H ^ at 35 $ of P ^ O ^ ^ 2 parts of ClNa, We obtain I hold 123 parts of a defluorinated phosphate having the following characteristics: 35, P 18.3% ι; 9 nr ~ ........................

F 0.08 ÿ.

Ca £ 29.5 | Na $ 6.4 d As 6.ppm, * ·! 5 crystalline phase Ma Ca (PO) 9 \%! 3 6 4 5! ! {j; crystalline phase apatite not removed • »crystalline phase tricalcium phosphate 3 $ citric solubility 92% EXAMPLE 8 d 10 This example is carried out with the same phosphate maro j. cain and under the same conditions as Example 7 but used 25 parts of anhydrous S0 Na instead of CINa. 123 parts are obtained 4 2 * of a defluorinated phosphate having the following characteristics: 13 P 18.3 g j [F 0.09 £ • Ca 29.5 g i Na '6.4% ι; As 6 ppm 2Q | crystalline phase Na Ca (PO) 90% || 3 6 4 5 • · I apatite crystal phase. undetected 'i t # crystal phase tricalcium phosphate 4 $. citric solubility 91.6% y *. · •! : i ·! i i! i

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Claims (3)

5. F <$ 0.2 • j · Ca ^ 25 £ j Na 6 - 10% j · [I; . As * <10 ppm! | crystalline phase Na Ca- (P0) _ 70% | 3 6 4 5 1C crystalline phase apatite <C 1 $ crystalline phase Ca ^ (PO ^) ^ ß <5% | Citric solubility 90 $ l h l | j | 2 - Phosphate according to claim 1 wherein the phosphon content | j is between 18 and 19% · I 1! · 3 - Phosphate according to either of Claims 1 and 2, in which the solution | "| g j citric bility is greater than 94%. t: 'I I; i. t · · · 4. Method of manufacturing calcium phosphate by heat treatment according to one of claims 1 to 3 from i | · Natural phosphates including a preliminary attack of I. .20, ore with phosphoric acid and a sodium derivative, a con! | j addition into granules of the product thus obtained with recycling I j of the fines, a defluorination by calcination with the addition of ji steam, and a quenching characterized in that: If jjj 4.1 - The attack is carried out by adding all of first of all with phosphoric acid and then after a reaction time * greater than 5 minutes, the sodium additive and the recycled fines, the reactants being introduced in an amount such that in the final product the molar ratios CaO / Na ^ O / P ^ D ^ are between 7 »6/1 / 2.9 and 3.6 / 1 / 1.5. / * ιΗ,! * * 4.2 - The conditioning is carried out at a drying temperature above ‘10 ° C. by the smoke from the colci- | nation in the form of granules of size between B 0.5 d i and 5 mm, d S: 4.3 - The defluorination by calcination is carried out at a I | temperature between 1 1D0 ° C and 1 3D0 ° C using as: | ! } oxidizing the preheated air during quenching,! 4.4 _ The hardening of the calcined product is carried out h i | air at a temperature below 60 ° C in less than two minutes. * * i •. f | ;! . dd 5 - Process according to claim 4, in which sodium carbonate is used in the preliminary attack as sodium reagent, " 6. The method of claim 4 wherein is used in the preliminary attack as sodium hydroxide reagent sodium! 1 i, II ”: 15 j 7 - Process according to claim 4, in which the calcination carried out i J in a fluidized bed at a temperature of 1,150 to 1,250 ° C is preceded t dj by preheating to 700 - 800 ° C by the fumes coming out of the calci-! | nator,. . h, • · I t *, »# I! : »B - The method of claim 7 wherein the preheating is effected • 20 killed by direct exchange of calories between the fumes. of the calciner and the product supplied, '. * i. · 'I j; ! s} 9 - Process according to claim 4 wherein the calcination is carried out! i killed in a rotary kiln with a maximum temperature between 1150 ° C and 1250 ° C · 2! 10 - Use of phosphate according to one of claims 1 to 3 as a supplement for animal feed or as a constituent of supplements for animal feed, '/ -, \ \ - -'. w.