UA73096C2 - Method for formulating alkali metal salts (variants) - Google Patents

Abstract

Methodology for formulating sodium bicarbonate and potassium sulfate. In one embodiment, sodium sulfate and ammonium bicarbonate are reacted to form sodium bicarbonate with the remaining liquor or brine treated with sulfuric acid to remove carbonates with subsequent precipitation of potassium sulfate. A further embodiment employs ammonium bicarbonate, ammonia gas or carbon dioxide to precipitate sodium bicarbonate. The result of the methods is the production of high quality fertilizer and food grade sodium bicarbonate.

Description

Description of the invention

The present invention relates to a method of obtaining alkali metal salts, namely, present invention 2 relates to a method of producing sodium bicarbonate of food quality and potassium sulfate as a fertilizer.

A large number of previous methods have been published in connection with the formation of alkali metal salts. As you know, sodium bicarbonate, for example, is produced in many different ways. However, previous stand-alone bicarbonate synthesis operations were hampered by inefficient energy use, which directly resulted in increased synthesis costs. A further obstacle was that known processes inefficiently carried out the 70 separate operations that make up the process of making salts. Of course, a separate high-quality product is obtained with the formation of a secondary product, which is inadequate in quality for commercial purposes, or which would also require significant investments in order to add commercial value to it.

US patent No. 3,429,657 dated February 25, 1969, owned by R'Ags, is illustrative. The specified patent relates to the method of obtaining and producing potassium salts. In this reference, potassium produced from saline 12 reacts with sodium perchlorate to precipitate potassium perchlorate. Potassium is removed by replacing it with a sodium ion, and free potassium is then bound by chloride, sulfate, and nitrate.

The actual invention is used in the production of fertilizers.

One embodiment of the proposed invention, which provides a method of obtaining food grade sodium bicarbonate and potassium sulfate, is characterized by the fact that it includes the following stages: a) preparation of the initial liquid sodium sulfate;

B) preparation of initial ammonium bicarbonate; c) contact of sodium sulfate and ammonium bicarbonate; a) precipitation of sodium bicarbonate and formation of a solution; e) precipitation of sodium bicarbonate and formation of a solution by contacting the solution obtained in step a) with sodium sulfate; Gee)

C) saturation of the solution obtained in step e) with sodium sulfate; 9) filtration of solid sediments from the solution obtained at stage E);

I) contact of the solution obtained at stage E) with sulfuric acid to precipitate carbonates; i) cooling of the solution obtained at stage M) to 02C before the formation of Glauber's salt precipitate; eh

І) heating the solution obtained in stage i) to a temperature in the range of 30-409С; and Ge)

K) precipitation of potassium sulfate by contacting the solution obtained in step |) with potassium chloride.

Another variant of the implementation of the present invention is provided by the method of obtaining food-grade sodium bicarbonate and potassium sulfate, which is characterized by the fact that it includes the following stages: a) preparation of the initial liquid sodium sulfate;

B) preparation of initial ammonium bicarbonate; - c) contact of sodium sulfate and ammonium bicarbonate; a) precipitation of sodium bicarbonate and formation of a solution; e) precipitation of sodium bicarbonate and formation of a solution by contacting the solution obtained in step e) with "sodium sulfate; from 7) saturation of the solution obtained in step e) with anhydrous sodium sulfate; c 9) filtration of solid deposits from the solution obtained at stage b); :z» P) contacting the solution obtained in step 9) at least with ammonium bicarbonate, ammonia gas or carbon dioxide to precipitate sodium bicarbonate; i) cooling the solution obtained at stage M) to a temperature of 09C until the precipitation of sodium bicarbonate and -1% of sodium sulfate; and

І) precipitation of potassium sulfate by contacting the solution obtained in step i) with potassium chloride/ (95) The cooled solution to a temperature of 02С was used to remove sodium sulfate as Glauber's salt and sodium bicarbonate. The solubility of Glauber's salt in the system is considered on the ammonium sulfate - sodium sulfate phase diagram. With an increase in sodium sulfate in the bicarbonate cycle with increased recirculation and) Glauber's salt, there is a tendency to decrease the solubility of bicarbonate and increase the efficiency

F process.

With regard to the conversion of the starting reagents to potassium sulfate, particular success has been achieved by establishing a molar ratio of five (5) or greater for the potassium and ammonium ions. This ratio ensures high conversion efficiency in the second stage of the process.

Fig. 1 shows a flow diagram of the process, its first part, according to the invention; (F) Figure 1a shows the second part of the process depicted in Figure 1;

GI Fig. 15 shows the third part of the process depicted in Fig. 1;

Fig. 2 shows a variant of the first part of the process flow diagram, according to the invention; in Fig. 2a shows the second part of the process depicted in Fig. 2; and

Fig.25 shows the third part of the process depicted in Fig.2.

The same numbers on the figures mean the same elements.

We refer to the drawings from Fig. 1 to Fig. 1b, which illustrate the process according to the first variant.

The starting liquid sodium sulfate 1 was dissolved in pure water and in water from channel 2, which is described hereafter. 65 The solution was mixed in container C at a temperature of 4092 to a relative density of 1.30. The solution was filtered through filter 4, which, according to the example, has a 5-micron filter. The solid residue 5 is removed until the filtrate 6 passes into the first crystallization container 7 of sodium bicarbonate.

Portions of water, ammonia, and carbon dioxide, all numbered 8, interact in container 9 to form ammonium bicarbonate. The resulting ammonium bicarbonate is centrifuged in a centrifuge 10, and the solid product is sent to the crystallization tank 7. The recirculation unit 11 returns the solid particles of ammonium bicarbonate and the solution to the reaction tank (not shown in Fig.). The result of combining in the reaction vessel is the production of sodium bicarbonate. The mixture is filtered with filter 12 and centrifuged. Sodium bicarbonate is washed with water in container 13, centrifuged in centrifuge 14, and the solid residue is food grade sodium bicarbonate.

The wash water is returned to container 3. 70 The solution after filter 12 has a relative density of 1.25, contains approximately 10.495 sodium sulfate, 17.195 ammonium sulfate, 895 sodium bicarbonate, and excess ammonium bicarbonate due to reaction with Glauber's salt (discussed below). The solution is treated in vessel 15 at a temperature of 40 °C with Glauber's salt, which was formed during the cooling phase, which will be discussed later, to form sodium bicarbonate from excess ammonium bicarbonate from the crystallization vessel. Alternatively, ammonium bicarbonate can be added 7/5 in the second stage (15 container) as a solid additive, suspension or solution.

Liquid from container 15 is added to solid sodium sulfate from source 16 for mixing in container 17 to produce a saturated sodium sulfate/ammonium sulfate solution. Sufficient ammonium bicarbonate must be present to complete the reaction as a solution or must be added to produce a solution having a specific gravity of 1.285. The suspension from container 17 is filtered through filter 18. The solid component of bicarbonate 20 Sodium 22 is sent to container 13, and solution 20 further interacts with an additional part of sodium bicarbonate, which is returned to container 13. Then solution 20 is sent to container 21 (Fig. 1A). The performance of the cycle relative to the sodium bicarbonate cycle can be monitored by evaporating a portion of the purified sodium sulfate to produce solid sodium sulfate, which provides a saturated cycle.

We refer to Fig. 1A, which shows that the container 21 contains sulfuric acid for precipitation of carbonate c 25 components. In this way, the processed solution is cooled to a temperature of 02C in container 22 for obtaining

Glauber's salt and filtered through filter 23. The resulting Glauber's salt is returned to the crystallization container and) sodium bicarbonate.

The filtrate, heated to a temperature of 30-409C in the container 24 and combined with the solid residue of the filter 26, contains 25.25 wt. 95 of ammonium sulfate and more than 11 wt. 96 of sodium sulfate. This solution is placed in "(0 container 27, where the solid potassium chloride is converted to obtain 20 wt. 906 of ammonium chloride solution, which also contains about 20.2 wt. 95 of ammonium chloride, 6.795 of potassium chloride, 4.995 of sodium chloride, 2.395 as F 092505, where x is Ma, K, and a solid mixture of potassium sulfate crystals with 10-2095 ammonium sulfate. (ав)

The solution is filtered in a filter 28 to a solid residue containing approximately 5 by weight 956 of potassium chloride, 80-8596 of potassium sulfate, 10-1595 of ammonium sulfate. The solid fraction is combined in container 29 with water and a saturated solution of potassium chloride from container 30. The solid residue of potassium sulfate is centrifuged and filtered in filter 31 and recrystallized with a solution of potassium chloride at a temperature of 2590. The remaining ammonium sulfate is converted into potassium sulfate. The amount of potassium sulfate reaches more than 98965.

At the following separate stages of the process, the solution or filtrate from the stages of obtaining potassium sulfate and especially after the filter 28 is processed according to separate stages similar to those shown in Fig. 1a. The solution is evaporated in the evaporator 28a to increase the concentration of the ammonium chloride solution so as to minimize the cooling of potassium chloride and residual sulfates in the solution. The solution is filtered in the filter 26 and the solid residue 25 is returned to the container 27. The filtrate, containing approximately 22-3095 ammonium chloride, is treated with lime in the reactor 32 with the release of recycled ammonia. The formed calcium chloride can be placed in a sump 33 or cleaned 34 depending on the purpose of the next use.

We give one example of the implementation of the method, bearing in mind the similarity of other options. - and Example 1 si Pre-quenching of bicarbonate before the potassium sulfate process

1 liter of solution with a relative density of 1.3, containing ZbOg/l Ma»zOu, is supplied to the inlet. (c) 1st stage p 50 Manso production

Salt solution output at the end of the reaction: 42) 130g Ma2304 10.495 Ma»ZOd 4090 213.8g (МНА)25О4 17195 (МНА)5О2 0.95 l of a solution with a relative density of 1.25 100 g MANSOZ 8.096 MANSOZ

GF) 807g But 1350.8g o This is 172g of solid residue Estimates of the second stage

Mmansoz is consumed 55g MNUZ A) 25.071MNaI kt 649202 bo 142.5g СО2 B) 51.2 gМНН132.6 gСО2 w 2nd Stage in 0.95l of salt solution the following will dissolve: b5

A) 1 gram-molecule of Ma»gh30410Н20 (332Gg) B) 2 gram-molecules of Ma250410Н2гО (644g)

pa 11 2nd STAGE The final composition of the solution of avavorosiu 10000000 rosaeomiu 1111

Bicarbonate quenching is dark; | VKD'auns, with 10100000 o

It turns out: 412g (MnSO, SO 35g Ma»5O, 1267g NiO me) 2014g at 1.265-(1, bl) o it is necessary to add Ma»5O to saturate to a relative density of 1.30 1.6l x 1.30-2080 and,

So: cha 412g (MNA»ZO, X 400g Ma»ZO, 1267g NO 2079g of the whole (1.bl) salt solution "

Cooling -o s 412g (МНА)»8О4 28,796 :з» 116бгма»8О4 8,096 807 No 539 1435g. Solution -I

Supply of substance to the outlet of the evaporator: (95) o MNASI 330.8g 21.996 so 50 KSI 13Ogo 8.696 mass 94.7g 6.396

F x-804 50 3,396

NO 907g 600 1512g (F) At 3395 MNASI in this case: - 2.895 KSI, ko in this case: - 2.095 KoZO4 vo So Z. ddog pz

Evaporating weight. - 907-623-284g 0.79t/t Ma»zO, 0.5bt is added for washing 65 1.29t NgO/t Ma»b5O,

Reaction of K»zO,

c) BO from (NI, vO- 174 - BAZG b) 50 from ueOd - x174 142 142 c) loss of K»ZO,y --43g

Total KoZO, 642 gG

Determination of the amount of KSI a) mixing reaction Ks 85. 274 - BOG 174 b) loss of KSI at the end - 50g c) therefore: KSI is necessary - 632g output 804 - b x 100 - 83,796

Be

Conversion performance is 882100 8215 6532

Basic calculation for loading 1 ton of Ma»25O, 2 tons 00000000 tons 00000000 tons

A filter for the production of a pure saline solution

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We turn to Fig. 2-20, which schematically shows the scheme of another process. In this reaction scheme, before the production of sodium bicarbonate, the solutions are saturated with anhydride.

FO In this version, sodium bicarbonate is made in the crystallization tank 7 and is generally subjected to actions similar to those shown in Fig. 1-15. The salt solution or filtrate is saturated with anhydrous sodium sulfate in container 15 and filtered on filter 12a to remove the insoluble residue, which is discarded. The filtrate after this operation reacts with ammonium bicarbonate in vessel 36. Otherwise, the filtrate can react with carbon dioxide or ammonium to precipitate sodium bicarbonate. The solution is filtered in filter 37 and the sodium bicarbonate remains.

F. Then it is combined with sodium bicarbonate after filter 12 and after that it is washed, centrifuged and co-dried. These stages are not shown.

The remaining filtrate has a composition of approximately, by weight, 10956 of sodium sulfate, 2495 of ammonium sulfate, and 895 of sodium bicarbonate. The solution has a specific gravity of 1.285 at 4026.

After this step, the filtrate solution is cooled in a cooler 38 to approximately 02 to obtain a filtrate containing approximately, by weight, 595 sodium sulfate, 2895 ammonium sulfate, and 695 sodium bicarbonate. The solution is filtered on filter 39 and the separated sodium bicarbonate and sodium sulfate are returned back to the crystallization tank of bicarbonate 15, while the filtrate reacts with potassium chloride in tank 40 on 65 of the first stage of the synthesis of potassium sulfate with a purity in the region of 7595-9095. The solid residue of potassium sulfate is moved together with the potassium chloride solution from container 41 to container 42. This leads to high quality, to a high degree of purification of potassium sulfate. The product is washed with water obtained in stage 43, which is returned to the container 42.

The solution after the filter 44 is evaporated in the evaporator 45 (Fig. 2A) to concentrate liquid ammonium chloride, with

Therefore, the cooling of potassium chloride and sulfates is minimized. The solution is filtered using filter 46, with a precipitate of potassium chloride and (x)5O,, where x is K, M, returned to container 40.

The filtrate from the filter 46, containing ammonium chloride, potassium chloride and potassium sulfate, is sent to the evaporator 47. The sodium bicarbonate reacts again and as a result carbon dioxide and ammonium are obtained. These gases are collected and stored for use in suitable equipment. The resulting calcium chloride is either thrown away or sold. 70 Example 2

Unquenched bicarbonate

1 liter of a solution with a relative density of 1.3, containing ZbOg/l Ma»zO, is supplied to the outlet. 1st stage

Production of MansSoz

Salt solution output at the end of the reaction: 130g Ma25O4 10.4956 Ma»3Od 40 213.8g (МНА)2504 17.195 (МНА)5О»2 0.95 l of a solution with a relative density of 1.25 100g MANSOZ 8.096 MANSOZ 807g No 1350.8g

This is 172g of solid residue

Mmansoz is consumed 55g of МНз 142, Bg СО» with o

Re-saturation with Ma»5ZO,: the salt solution contains 150 g of Ma»5O,). This salt solution is then filtered and fed to the second stage of ManCOz crystallization.

F

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Eto: INN MON Ese NN MON F due 01 July 1 So RN MON SU WM NOV

Zo : - : - - ply solution of relative density 139, tives of erosion of the relative lip 1266

The saline solution is then cooled to 0260. « 20 The composition of the saline solution is as follows: 5.095 Ma 2503, which means the god Ma»5O), precipitates 136g of Ma»5O/10Н50 from the precipitate and 76bg of HO is removed.

So: 907-76-831g N.O. :z» The composition of a salt solution at 02C and a relative density of 1.26. 7Og Ma»zO,

Z53g (MNA)» ZOH - and 100g ManSoO» 831g HO and 1354g in total About 1 liter of salt solution KoZO,. so bo 000 LY My your x 174 - VB,8G sv 6) 353 МН 474 - 456 ЗИ 132

Output of salt solution: about 1 70 lovogusei

Evaporation up to 33.095 MNASI.

Separation of MH" and CO" from the evaporator, but MNASI salt is formed from KSI, not Masi. KSI is obtained exactly as in example 1. b5 Basic calculation for loading 1t of Ma»25O,

The first stage of ivTMNU omvemansoi byaetsyu 1 nyu 11 deumystya 0olognne bzhimanooya nin ti nin po kh nina and Cooling dob'SI 0 ayatmezhvomonyu

Salty rum 0000000 oyeemavoy z 000000bevemnoyvokh ryu 010000000bevemansoz yayu 5 with a clear hand » 0 banyuobovika 00 ooyuvo yan 010000 schrya 1

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Example C ("in")

Bicarbonate quenching without evaporation of ammonium chloride so

A portion of the solution: from Мо1 412 g (МНА) d2ЗО4 h-

Z35Hg Ma504 1267g NO 2014g at a relative density of 1.265-1.60l "

Cooling of the filtered solution to a temperature of 02C: c) s h» A12g (МНА)»8О4 28.796 " 11vgMa»?8O4 8.096 807g No 75 1435g of solution -I oz Then this solution is heated to a temperature of 252С, to which a solid residue of KSI is added to obtain o K»ZO,. The final output of the salt solution from the closed cycle Ko5O has the following composition: со 020 МНАСИ 330.8 g 21.996

KSI 130g 8.696 that weighs 94.7g 6.396 x-8O4 BOG 3.396 x-Ma/K

NgO 807 years in a total of 1512 years

HF This solution is then heated and reacts with lime to release ammonia and bypasses the evaporator. KSI passes into a solution of SaSSi". This leads to 15-2095 losses of K in the SaSSi solution. The amount of KSI can be reduced to about 1.096 by adding solid Ma 2504 to the Sasi/KSI solution. Potassium is efficiently collected as precipitated syngenite (Sazo,-CoZO,-x20) at temperatures from 02С to 1002С, at an optimal temperature of 20-30 because the solubility of 50 is kept to a minimum, and the reaction proceeds with an acceptable speed.

The composition of the saline solution SasSi" 343.3g Sasio 22.595 b5 130g KSI 8.596

94.7 mass 6.395

BOgh 804 3295 (Ma/K) 907гНгО 59595 1525Бг 10095

Addition of 140 g of Ma»zO,:

Yield of salt solution Yield of filtered sediment 70 234.8g Sasio 17.896 15.25g KSI 1.196 З310g Savou-К»вО4 209g Masi 15.9964100g. BUT

BOg x 04 3,896 8Otg 61,396

The starting salt solution can be saturated well removed, and the filtered precipitate can be mixed with the product CoZO, as a binder or further used in the process to remove Sabo).

Filtered sediment can react with (МНА)»НСО;» from the initial process MansSoO»z, and Savo, reacts quickly, producing a solution of salts (МНА)»5О, and K»ZO, and the sediment on the Sasi filter that was formed. The (MH)»5O4/K»5O solution is returned to the KoZO crystallizer, the first stage. what is 5 p

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Claims (1)

The formula of the invention from c 1. The method of obtaining salts of alkali metals: sodium bicarbonate of food grade and potassium sulfate, which "" includes the following stages: a) preparation of the initial solution of sodium sulfate; B) preparation of the initial ammonium bicarbonate for the precipitation of sodium bicarbonate; -I c) contact of the mentioned sodium sulfate with the mentioned ammonium bicarbonate; с a) precipitation of sodium bicarbonate and formation of a solution; f) filtering of the mentioned sodium bicarbonate; ав) C) saturation of the solution obtained in step e) with sodium sulfate; со 50 9) contacting the mentioned solution with ammonium bicarbonate, ammonia gas or carbon dioxide for further precipitation of sodium bicarbonate; 4) I) filtering of the precipitated sodium bicarbonate obtained in step 9); i) combining the sodium bicarbonate precipitated in steps e) and p) and washing to obtain food-grade sodium bicarbonate; )) treatment of the solution obtained at stage n) with sulfuric acid to convert carbonate salts into sulfate salts and emission of carbon dioxide; o K) cooling the solution obtained at stage |) to 0 °C for precipitation of at least Glauber's salt; ie) I) heating the solution obtained at stage K) to 30-40 oC; and t) precipitation of potassium sulfate by contacting the solution obtained in step I) with potassium chloride. 6о0 2. The method according to claim 1, which differs in that it further includes the step of separating the precipitated potassium sulfate and washing with potassium chloride. C. The method according to claim 2, which differs in that it further includes the step of treating the solution obtained at the step of separating the precipitated potassium sulfate with lime to release ammonia gas. 4. The method according to item 3, which differs in that it further includes the step of recirculation of the mentioned ammonia gas to the 65th step ad). 5. The method according to claim 4, which differs in that it further includes the step of evaporating the filtrate obtained according to p. 6. The method according to claim 1, which differs in that the sodium sulfate mentioned in step 1) has a relative density of 1.30 to 1.34 at 40 26. 7. The method according to claim 1, which differs in that the mentioned solution obtained in step a) has a relative density of 1.25 and contains by weight 10.4 95 of sodium sulfate, 17.1 96 of ammonium sulfate, from 8 95 to 12 95 sodium bicarbonate and an excess of ammonium bicarbonate. 8. The method according to claim 1, which is characterized by the fact that the mentioned sodium sulfate, obtained at stage 1), includes Ma»ZOu-10H20. 70 9. The method according to claim 1, which is distinguished by the fact that the mentioned solution, obtained in step i), has a relative density of 1.285 at 40 26. 10. The method according to claim 1, which is characterized by the fact that the mentioned solution obtained in step |) is a saturated solution of sodium sulfate, ammonium sulfate, and sodium bicarbonate. 11. The method according to claim 1, which is characterized in that at least 80 905 of said potassium sulfate 75 is obtained as a result with a purity of at least 98 90. 12. The method of obtaining salts of alkali metals: sodium bicarbonate of food grade and potassium sulfate, which includes the following stages: a) preparation of the initial solution of sodium sulfate; B) preparation of initial ammonium bicarbonate; c) contact of the mentioned sodium sulfate and the mentioned ammonium bicarbonate; a) precipitation of sodium bicarbonate and formation of a solution; e) precipitation of sodium bicarbonate and formation of a solution by contacting the mentioned solution obtained in step 4) with sodium sulfate; C) saturation of the solution obtained in step e) with sodium sulfate; Ha 9) filtration of the solid sediment from the mentioned solution, obtained at stage Her); o P) contacting the mentioned solution, obtained at the stage of Her), with sulfuric acid; i) cooling the solution obtained at stage M) to 0 °C to form a precipitate of Glauber's salt; І) heating the solution obtained in stage i) to a temperature in the range of 30-40 oС; K) treatment of the solution mentioned in step )) with potassium chloride to precipitate potassium sulfate; (Ce) I) evaporation of the solution obtained in stage K) to return potassium for reuse in stage F UK). 13. The method according to claim 12, which is characterized by the fact that it further includes the step of processing the solution remaining after (and) step I) with lime and ammonium chloride. with 14. The method according to claim 13, which differs in that ammonia gas is isolated and returned to the cycle. 15. The method according to claim 12, which differs in that the used potassium chloride is returned to stage K). - Official bulletin "Industrial Property". Book 1 "Inventions, useful models, topographies of integrated microcircuits", 2005, M 6, 15.06.2005. State Department of Intellectual Property of the Ministry of Education and Science of Ukraine. - and? -i (95) («c) se) 4) ime) 60 b5