WO2001042172A1 - Process for the preparation of urea superphosphate fertilizers - Google Patents

Process for the preparation of urea superphosphate fertilizers Download PDF

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Publication number
WO2001042172A1
WO2001042172A1 PCT/IL2000/000824 IL0000824W WO0142172A1 WO 2001042172 A1 WO2001042172 A1 WO 2001042172A1 IL 0000824 W IL0000824 W IL 0000824W WO 0142172 A1 WO0142172 A1 WO 0142172A1
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Prior art keywords
process according
urea
superphosphate
ground
phosphogypsum
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PCT/IL2000/000824
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French (fr)
Inventor
Yuval Swissa
Eliahu BEN-JOSEPH
Original Assignee
Rotem Amfert Negev Ltd.
Kogan, Leni
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Filing date
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Application filed by Rotem Amfert Negev Ltd., Kogan, Leni filed Critical Rotem Amfert Negev Ltd.
Priority to AU18807/01A priority Critical patent/AU1880701A/en
Publication of WO2001042172A1 publication Critical patent/WO2001042172A1/en

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    • C—CHEMISTRY; METALLURGY
    • C05—FERTILISERS; MANUFACTURE THEREOF
    • C05C—NITROGENOUS FERTILISERS
    • C05C9/00—Fertilisers containing urea or urea compounds
    • C—CHEMISTRY; METALLURGY
    • C05—FERTILISERS; MANUFACTURE THEREOF
    • C05B—PHOSPHATIC FERTILISERS
    • C05B1/00—Superphosphates, i.e. fertilisers produced by reacting rock or bone phosphates with sulfuric or phosphoric acid in such amounts and concentrations as to yield solid products directly
    • C05B1/02—Superphosphates

Definitions

  • This invention relates to an improved process for the preparation of urea superphosphate fertilizer, which process comprises only one chemical stage and is simpler and more economical than the methods of the prior art.
  • Urea superphosphate is made from urea, which is a cheap source of nitrogen, and from phosphate rock as a cheap source of P2O5.
  • the powder or granules of urea superphosphate can be used as fertilizer.
  • the urea superphosphate can also be granulated with other fertilizers, such as KC1, K 2 SO 4 , MAP or DAP (monoammonium or diammonium phosphate) , to obtain the desired NPK (nitrogen-phosphorus-potassium) compounds.
  • One of the advantages of the present invention is the production of urea superphosphate that in bulk blending is compatible with fertilizers such as urea and triple superphosphate (TSP).
  • fertilizers such as urea and triple superphosphate (TSP).
  • USP 5,409,516 discloses a method of making phospho-nitrogenous products in two stages: first, preparing a sulfo-ureic reagent by reaction of concentrated sulfuric acid with urea, and secondly, reacting the sulfo-ureic reagent with tricalcium phosphate.
  • the combination of urea with sulfuric acid, giving mono-ureic and di-ureic sulfate, is exothermic, so that the preparation of the sulfo-ureic reagent needs temperature control and heat exchanger means.
  • the reaction between said reagent and the tricalcium phosphate forms tetra-urea calcium sulfate, which makes the product free of excess urea.
  • First stage of this process - preparation of the sulfo-ureic reagent - besides requiring controlling conditions, is prohibitively expensive.
  • urea superphosphate that is compatible with fertilizers, such as urea and triple superphosphate (TSP).
  • fertilizers such as urea and triple superphosphate (TSP).
  • the process according to the present invention comprises reacting ground urea and ground phosphate rock with sulfuric acid in a single stage, in the presence of gypsum or phosphogypsum.
  • phosphoric acid can be added to the reaction mixture.
  • the reagents are preferably added simultaneously to a reactor.
  • the urea is ground to an average granule size of not more than 3 mm and preferably not more than 1 mm.
  • the main fraction, viz. 80-90% by weight, of the ground urea has a granule size of less than 1 mm.
  • the phosphate rock is also ground, preferably to such an extent that about 90% by weight thereof is reduced to a size of less than 0.15 mm.
  • Gypsum or phosphogypsum is added in an amount from 2% to 10%, and preferably about 6%, of the total weight of the raw materials, calculated as dry calcium sulfate dihydrate. It is added in the reaction stage as a binder to obtain the desired physical properties of the powdered urea superphosphate and the granulated urea superphosphate and to bind unreacted urea molecules, if such are present.
  • the ratio of sulfuric acid to urea depends on the desired final product composition. E.g., if the product is urea superphosphate 20-10-0, said ratio is about 3.
  • Water may be added to the reagents in order to obtain the desired humidity in the urea superphosphate powder finally obtained, but has no influence on the reaction. In general, it is from 4% to 14%.
  • the reaction is carried out at temperatures from 50 to about 110°C and preferably from 70 to 90°C.
  • the duration of the reaction is typically from 0.5 to 6 minutes.
  • urea superphosphate (hereinafter, USP), is produced from rock phosphate, urea, sulphuric acid, and gypsum or phosphogypsum, with or without the addition of phosphoric acid.
  • USP powder and granules with the composition 20-10-0 (20% N, 10% P 2 O 5 and 0% K 2 O), but this should not be construed as a limitation, since USP can be produced, according to the invention, with different compositions.
  • Urea superphosphate (hereinafter, USP), produced according to the invention, can be granulated or bulk-blended or granulated with other fertilizers.
  • Phosphogypsum contains about 98% of calcium sulfate dihydrate.
  • gypsum calcium sulfate dihydrate (gypsum) or monohydrate or anhydrous calcium sulfate could be used in place of phosphogypsum.
  • Phosphogypsum is a convenient raw material and therefore the invention will be described with reference to it.
  • Gypsum could also be used and would have the same functions. It was also found that phosphoric acid could be added to increase the P2O5 concentration in the product, and to compensate the effect of dilution caused by the addition of the gypsum or phosphogypsum.
  • the phosphogypsum used in the examples contained about 98% CaS0 4 .2H 2 0 with 0.7% ground rock phosphate and 0.4% phosphoric acid, but in other cases the concentration of ground rock phosphate can vary from 0.2 to 1.0% and that of phosphoric acid can vary from 0.2 to 1%.
  • the process of the invention is preferably carried out as follows.
  • the raw materials - ground phosphate rock, urea, gypsum or phosphogypsum, sulfuric acid, with or without phosphoric acid and water - are added simultaneously to a reactor, e.g. a Khulman type reactor, or a pug mill.
  • the urea has been previously ground to grain size ⁇ 3 mm, preferably ⁇ 1 mm.
  • the granulometry of the urea is: 5% +2mm, 6% +1 mm, and 89% 1mm or less.
  • the temperature of the reactor is about 70°C.
  • the reaction product solidifies after about a minute or two.
  • the resulting powder of urea superphosphate has a humidity of 5.5-6.5% and generally comprises granules of sizes up to about 2 mm, is not hygroscopic, and has good friability and storage properties.
  • Granulation of the said powder could take place immediately after the reaction product has solidified, or after curing for several days. It is carried out in several stages, wherein a recycle to each stage from the previous stage depends on the composition of the NP fertilizer.
  • the granulation was made by using fresh urea superphosphate and recycle of the same from the previous granulation stage, in a weight ratio of about 1:1.
  • the humidity in the mixture of fresh material and recycle is about 5%.
  • the granulation is sensitive to the addition of water.
  • the granulation is carried out at a temperature from 40 to 80°C, preferably at about 50°C, this temperature being achieved by the addition of steam or, preferably, of hot water.
  • the humidity of the granules from the granulator was kept between 5.5 and 6%.
  • pH correction is needed in order to obtain the desired physical properties. This can be done by adding a base, preferably, ammonia.
  • the granules thus obtained are then dried to obtain a granular humidity of about from 1% to 2%.
  • the drying of the granules is carried out with hot air at about 80° C to 90° C.
  • the temperature of the granules does not exceed 70°C.
  • the dried granules are screened to obtain a product size of 2-5 mm.
  • the +5 mm fraction is crushed and used together with the —2 mm fraction as a recycle for the next granulation.
  • the dried product granules were put in a humidity chamber at 70% humidity and 25°C for several hours. Then they were mixed with urea at a weight ratio of 1:1.
  • NPK fertilizers such as 8-24-8 or 12-12-12.
  • other compounds of NPK such as 15-15-15, could be produced.
  • a solid mixture of 344 g of ground phosphate rock (32.2% P2O5), 445 g of ground (-1 mm) urea (44,2% N) and 63 g of phosphogypsum was added to the reactor. Simultaneously were added 196 g of 98% H2SO4 and 63 g of water. The temperature in the reactor reached about 80°C. The urea superphosphate product in the reactor solidified after one minute, and contained about 8% moisture.
  • the powder was granulated in rotary drum.
  • the weight ratio of feed (powder of urea superphosphate) to recycled product (fine product from the previous granulation) was 1 to 1.
  • the reaction temperature was about 50°C, and was achieved by addition of steam.
  • the wet granules contained moisture of about 11%.
  • the granules were dried at 80-90°C to a moisture content of 1-2%.
  • the dried product contained 20.1% N, 11.4% total P 2 0 5 , 8.4% citrate soluble P2O5, 9.1% water soluble P2O5 and 2% free acid as P2O5.
  • the granules were compatible with urea.
  • Example 1 was repeated, but with the addition to the reagents of phosphoric acid, which in this case was obtained by the aforementioned WPA process, in order to increase the amount of citrate soluble P2O5 and of water soluble P2O5 in the product.
  • the quantities of the raw materials that were introduced to the reactor were: 588 g of ground phosphate rock (32.2% P2O5), 890 g of ground urea, 120 g of phosphogypsum, 320 g of 98% H2SO4, 84 g of WPA (50% P2O5) and 107 g of water.
  • the reaction temperature reached about 75°C. Solidification of the reaction product occurred after 1 minute. Moisture content was about 4%.
  • the powder after one week of curing, was granulated in a rotary drum.
  • the weight ratio of the feed to the recycled product was 1 to 1.
  • the temperature of about 50°C was achieved by the addition of steam.
  • the wet granules contained about 8% moisture.
  • the granules were dried at 80-90°C to a moisture content of about 1%.
  • the product contained 21.1% N, 12.3% total P2O5, 9.2% citrate soluble P2O5, 10% water soluble P2O5, and moisture content of 1.5%.
  • Example 2 was repeated, except that the reaction was carried in a pug mill. The following raw materials were fed at the following rates:
  • the reaction temperature in the pug mill was about 70°C, residence time was about 1 minute, and solidification occurred within two minutes. Powdered urea superphosphate was collected for about two hours.

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  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Fertilizers (AREA)

Abstract

Process for the production of urea superphosphate, which comprises reacting ground urea and ground phosphate rock with sulfuric acid in a single stage, in the presence of gypsum or phosphogypsum, or calcium sulfate monohydrate or anhydrous. Phosphoric acid may be added to the reaction mixture. The reagents may be added simultaneously to a reactor. The urea may be ground to an average granule size of not more than 3 mm, and preferably not more than 1 mm. The gypsum or phosphogypsum is preferably added in an amount from 2 % to 10 % relative to the total weight of raw materials.

Description

PROCESS FOR THE PREPARATION OF UREA SUPERPHOSPHATE FERTILIZERS
Field of the Invention
This invention relates to an improved process for the preparation of urea superphosphate fertilizer, which process comprises only one chemical stage and is simpler and more economical than the methods of the prior art.
Background of the Invention
Urea superphosphate is made from urea, which is a cheap source of nitrogen, and from phosphate rock as a cheap source of P2O5. The powder or granules of urea superphosphate can be used as fertilizer. The urea superphosphate can also be granulated with other fertilizers, such as KC1, K2SO4, MAP or DAP (monoammonium or diammonium phosphate) , to obtain the desired NPK (nitrogen-phosphorus-potassium) compounds.
One of the advantages of the present invention is the production of urea superphosphate that in bulk blending is compatible with fertilizers such as urea and triple superphosphate (TSP).
USP 5,409,516 discloses a method of making phospho-nitrogenous products in two stages: first, preparing a sulfo-ureic reagent by reaction of concentrated sulfuric acid with urea, and secondly, reacting the sulfo-ureic reagent with tricalcium phosphate. The combination of urea with sulfuric acid, giving mono-ureic and di-ureic sulfate, is exothermic, so that the preparation of the sulfo-ureic reagent needs temperature control and heat exchanger means. The reaction between said reagent and the tricalcium phosphate forms tetra-urea calcium sulfate, which makes the product free of excess urea. First stage of this process - preparation of the sulfo-ureic reagent - besides requiring controlling conditions, is prohibitively expensive.
It is a purpose of this invention to provide a simpler and more economical process for the preparation of urea superphosphate.
It is another purpose of this invention to provide a single-stage process for the preparation of urea superphosphate.
It is a further purpose of this invention to provide such a process that does not require heat exchange and therefore can be carried out with simpler apparatus.
It is a further purpose of this invention to produce urea superphosphate that is compatible with fertilizers, such as urea and triple superphosphate (TSP).
It is a still further purpose of this invention to produce urea superphosphate as a powder or granules.
It is a still further purpose of this invention to use urea superphosphate as a raw material in the production of powdered and granulated NPK fertilizers. Other purposes and advantages of the invention will appear as the description proceeds.
Summary of the Invention
The process according to the present invention comprises reacting ground urea and ground phosphate rock with sulfuric acid in a single stage, in the presence of gypsum or phosphogypsum. Optionally, phosphoric acid can be added to the reaction mixture. The reagents are preferably added simultaneously to a reactor.
The urea is ground to an average granule size of not more than 3 mm and preferably not more than 1 mm. Preferably, the main fraction, viz. 80-90% by weight, of the ground urea has a granule size of less than 1 mm. The phosphate rock is also ground, preferably to such an extent that about 90% by weight thereof is reduced to a size of less than 0.15 mm.
The weight ratio (all ratios in this description and claims are by weight, unless otherwise indicated) of P2O5 to urea moieties depends on the composition of the final product desired.
Gypsum or phosphogypsum is added in an amount from 2% to 10%, and preferably about 6%, of the total weight of the raw materials, calculated as dry calcium sulfate dihydrate. It is added in the reaction stage as a binder to obtain the desired physical properties of the powdered urea superphosphate and the granulated urea superphosphate and to bind unreacted urea molecules, if such are present. The ratio of sulfuric acid to urea depends on the desired final product composition. E.g., if the product is urea superphosphate 20-10-0, said ratio is about 3.
Water may be added to the reagents in order to obtain the desired humidity in the urea superphosphate powder finally obtained, but has no influence on the reaction. In general, it is from 4% to 14%.
The reaction is carried out at temperatures from 50 to about 110°C and preferably from 70 to 90°C. The duration of the reaction is typically from 0.5 to 6 minutes.
Detailed Description of Preferred Embodiments
According to the invention, urea superphosphate (hereinafter, USP), is produced from rock phosphate, urea, sulphuric acid, and gypsum or phosphogypsum, with or without the addition of phosphoric acid. The following examples relate to the production of USP powder and granules with the composition 20-10-0 (20% N, 10% P2O5 and 0% K2O), but this should not be construed as a limitation, since USP can be produced, according to the invention, with different compositions. Urea superphosphate (hereinafter, USP), produced according to the invention, can be granulated or bulk-blended or granulated with other fertilizers.
In the following examples, it is assumed that the phosphoric acid used was produced by a method called Wet Process Phosphoric Acid (WPA), which generates phosphogypsum as a waste. This method is described e.g. in Pierre Becker - Phosphates and phosphoric Acid, Marcel Dekker, Inc., 1993. Phosphogypsum contains about 98% of calcium sulfate dihydrate. As stated hereinbefore, calcium sulfate dihydrate (gypsum) or monohydrate or anhydrous calcium sulfate could be used in place of phosphogypsum. Phosphogypsum is a convenient raw material and therefore the invention will be described with reference to it. It is useful as a binder for the excess urea molecules and as a binder between particles of the urea superphosphate in the production of the powder both in the reaction and in the granulation stages. Gypsum could also be used and would have the same functions. It was also found that phosphoric acid could be added to increase the P2O5 concentration in the product, and to compensate the effect of dilution caused by the addition of the gypsum or phosphogypsum.
The phosphogypsum used in the examples contained about 98% CaS04.2H20 with 0.7% ground rock phosphate and 0.4% phosphoric acid, but in other cases the concentration of ground rock phosphate can vary from 0.2 to 1.0% and that of phosphoric acid can vary from 0.2 to 1%.
The process of the invention is preferably carried out as follows. The raw materials - ground phosphate rock, urea, gypsum or phosphogypsum, sulfuric acid, with or without phosphoric acid and water - are added simultaneously to a reactor, e.g. a Khulman type reactor, or a pug mill. The urea has been previously ground to grain size < 3 mm, preferably < 1 mm. In these examples, the granulometry of the urea is: 5% +2mm, 6% +1 mm, and 89% 1mm or less. The temperature of the reactor is about 70°C. The reaction product solidifies after about a minute or two. The resulting powder of urea superphosphate, has a humidity of 5.5-6.5% and generally comprises granules of sizes up to about 2 mm, is not hygroscopic, and has good friability and storage properties.
Granulation of the said powder, to granules of sizes generally about 2 to 5 mm, could take place immediately after the reaction product has solidified, or after curing for several days. It is carried out in several stages, wherein a recycle to each stage from the previous stage depends on the composition of the NP fertilizer. For NP 20-10, the granulation was made by using fresh urea superphosphate and recycle of the same from the previous granulation stage, in a weight ratio of about 1:1. The humidity in the mixture of fresh material and recycle is about 5%. The granulation is sensitive to the addition of water. The granulation is carried out at a temperature from 40 to 80°C, preferably at about 50°C, this temperature being achieved by the addition of steam or, preferably, of hot water. The humidity of the granules from the granulator was kept between 5.5 and 6%.
In some of the NPK (nitrogen-phosphorus-potassium) formula, pH correction is needed in order to obtain the desired physical properties. This can be done by adding a base, preferably, ammonia.
The granules thus obtained are then dried to obtain a granular humidity of about from 1% to 2%. The drying of the granules is carried out with hot air at about 80° C to 90° C. The temperature of the granules does not exceed 70°C. The dried granules are screened to obtain a product size of 2-5 mm. The +5 mm fraction is crushed and used together with the —2 mm fraction as a recycle for the next granulation. To examine the compatibility of the product of the process of the invention with urea, the dried product granules were put in a humidity chamber at 70% humidity and 25°C for several hours. Then they were mixed with urea at a weight ratio of 1:1. The mixture was placed in a furnace and heated at 50°C for several days. The result showed that the product did not react with the urea. It was further found that the product, which did not contain an excess of urea, was compatible with TSP (triple superphosphate) .
The powder urea superphosphate was granulated with KC1, TSP, SSP, MAP and ammonia to yield NPK fertilizers, such as 8-24-8 or 12-12-12. By the same method, other compounds of NPK, such as 15-15-15, could be produced.
Example 1
A solid mixture of 344 g of ground phosphate rock (32.2% P2O5), 445 g of ground (-1 mm) urea (44,2% N) and 63 g of phosphogypsum was added to the reactor. Simultaneously were added 196 g of 98% H2SO4 and 63 g of water. The temperature in the reactor reached about 80°C. The urea superphosphate product in the reactor solidified after one minute, and contained about 8% moisture.
After one week of curing, the powder was granulated in rotary drum. On granulation, the weight ratio of feed (powder of urea superphosphate) to recycled product (fine product from the previous granulation) was 1 to 1. The reaction temperature was about 50°C, and was achieved by addition of steam. The wet granules contained moisture of about 11%. The granules were dried at 80-90°C to a moisture content of 1-2%. The dried product contained 20.1% N, 11.4% total P205, 8.4% citrate soluble P2O5, 9.1% water soluble P2O5 and 2% free acid as P2O5.
The granules were compatible with urea.
Example 2
Example 1 was repeated, but with the addition to the reagents of phosphoric acid, which in this case was obtained by the aforementioned WPA process, in order to increase the amount of citrate soluble P2O5 and of water soluble P2O5 in the product.
The quantities of the raw materials that were introduced to the reactor were: 588 g of ground phosphate rock (32.2% P2O5), 890 g of ground urea, 120 g of phosphogypsum, 320 g of 98% H2SO4, 84 g of WPA (50% P2O5) and 107 g of water. The reaction temperature reached about 75°C. Solidification of the reaction product occurred after 1 minute. Moisture content was about 4%.
Again, the powder, after one week of curing, was granulated in a rotary drum. The weight ratio of the feed to the recycled product was 1 to 1. The temperature of about 50°C was achieved by the addition of steam. The wet granules contained about 8% moisture. The granules were dried at 80-90°C to a moisture content of about 1%. The product contained 21.1% N, 12.3% total P2O5, 9.2% citrate soluble P2O5, 10% water soluble P2O5, and moisture content of 1.5%.
Again, the product was compatible with urea.
Example 3
Example 2 was repeated, except that the reaction was carried in a pug mill. The following raw materials were fed at the following rates:
400 g/minute of solid mixture containing ground phosphate rock, ground
(-1 mm) urea and phosphogypsum (ratio as in Example 2);.
130 g/minute of liquid mixture containing H2SO4, WPA and water (ratio as in Example 2).
The reaction temperature in the pug mill was about 70°C, residence time was about 1 minute, and solidification occurred within two minutes. Powdered urea superphosphate was collected for about two hours.
Analysis of the urea superphosphate:
20.2% N, 12.2% total P2O5, 9.11% water soluble P2O5, 1.7% free acid as
P2O5, moisture content 3.1%.
Although examples of the invention have been described by way of illustration, it will be apparent that the invention can be carried out with many modifications, variations and adaptations, without departing from its spirit, or exceeding the scope of the claims.

Claims

1. Process for the production of urea superphosphate, which comprises reacting ground urea and ground phosphate rock with sulfuric acid in a single stage, in the presence of gypsum or phosphogypsum, or calcium sulfate monohydrate or anhydrous.
2. Process according to claim 1, further comprising adding phosphoric acid to the reaction mixture.
3. Process according to claim 1 or 2, wherein the reagents are added simultaneously to a reactor.
4. Process according to claim 1, wherein the urea is ground to an average granule size of not more than 3 mm.
5. Process according to claim 3, wherein the urea is ground preferably to an average granule size of not more than 1 mm.
6. Process according to claim 1, wherein the gypsum or phosphogypsum is preferably added in an amount from 2% to 10% relative to the total weight of raw materials.
7. Process according to claim 1, wherein the gypsum or phosphogypsum is added in an amount of 6% relative to the total weight of raw materials.
8. Process according to claim 1, wherein the ratio of sulfuric acid to urea depends on the desired final product composition.
9. Process according to claim 1, for the production of urea superphosphate fertilizer of composition of NPK 20-10-0.
10. Process according to claim 1, for the production of USP 20-10-0, wherein the weight ratio of sulfuric acid to urea is about 3.
11. Process according to claim 1, further comprising adding water to the reagents.
12. Process according to claim 7, wherein the amount of water added is such as to obtain urea superphosphate having a humidity content from 4% to 14%.
13. Process according to claim 1, wherein the reaction is carried out at temperatures from 50 to 110°C and preferably from 70 to 90 °C.
14. Process according to claim 13, wherein the temperature of the granules does not exceed 70°C.
15. Process according to claim 1, wherein the duration of the reaction is from 30 seconds to 6 minutes.
16. Process according to claim 1, further comprising the granulation of the reaction product.
17. Process according to claim 16, wherein the granulation is carried out in a rotary drum or a rotary plate.
18. Process according to claim 16, wherein the granulation is carried out at a temperature from 40 to 80°C.
19. Process according to claim 18, wherein the granulation is carried out preferably at a temperature of 50°C.
20. Process according to claim 16, wherein the humidity of the granules is from 5.5% to 6%.
21. Process according to claim 16, further comprising drying the granules at a temperature from 80 to 90°C until their humidity is reduced to 1-2%.
22. Process for the production of urea superphosphate, substantially as described and exemplified.
PCT/IL2000/000824 1999-12-09 2000-12-07 Process for the preparation of urea superphosphate fertilizers WO2001042172A1 (en)

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* Cited by examiner, † Cited by third party
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ES2164580A1 (en) * 2000-01-10 2002-02-16 Inabonos Sa Fabrication of phospho-urea agriculture mixture consists of grinding of rock phosphate, urea and calcium sulfate and treatment with acid
CN101519324B (en) * 2009-04-08 2012-02-22 吕庆淮 Long-effect compound fertilizer containing sulfur with high nitrogen, production method and application thereof
EP2774907A3 (en) * 2013-03-06 2015-02-11 Instytut Nawozów Sztucznych Method and plant for continuous manufacture of granular USP nitrogen and phosphate type fertilizers and products on their basis
US9328031B2 (en) 2012-08-29 2016-05-03 Yara International Asa Method for limiting the use of an ammonium nitrate fertilizer as a precursor for an explosive and composition therefor
WO2021009611A1 (en) 2019-07-12 2021-01-21 Sabic Global Technologies B.V. Urea phosphate calcium sulfate granules and methods for producing and using the same
WO2021064488A1 (en) 2019-10-03 2021-04-08 Sabic Global Technologies B.V. Urea calcium sulfate granules and methods for producing and using the same
WO2022003564A1 (en) 2020-07-01 2022-01-06 Sabic Global Technologies B.V. Methods for producing urea calcium sulfate from moist phosphogypsum
WO2022003558A1 (en) 2020-07-01 2022-01-06 Sabic Global Technologies B.V. Stabilized urea calcium sulphate adduct coated with a base an urease inhibitor
US11299441B2 (en) 2017-07-21 2022-04-12 Sabic Global Technologies B.V. Calcium sulfate urea granules and methods for producing and using the same

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Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB863387A (en) * 1958-06-30 1961-03-22 Ici Ltd Improvements in and relating to granular fertilizers
GB949345A (en) * 1961-12-20 1964-02-12 Lawes Chemical Company Ltd Improved method of producing granular fertilisers
GB1211537A (en) * 1966-12-02 1970-11-11 Power Gas Ltd Improvements in or relating to the production of fertilisers comprising urea phosphate
BR8103768A (en) * 1981-06-15 1983-01-18 Inst Pesquisas Tech FERTILIZER PRODUCTION PROCESS
WO1992010443A1 (en) * 1990-12-05 1992-06-25 Transvalor Method for obtaining phospho-nitrogenous products and products thus obtained
CN1063674A (en) * 1991-12-30 1992-08-19 郑州工学院 Granular compound fertilizer and technology thereof that the part acidic phosphorus mine single stage method is made

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB863387A (en) * 1958-06-30 1961-03-22 Ici Ltd Improvements in and relating to granular fertilizers
GB949345A (en) * 1961-12-20 1964-02-12 Lawes Chemical Company Ltd Improved method of producing granular fertilisers
GB1211537A (en) * 1966-12-02 1970-11-11 Power Gas Ltd Improvements in or relating to the production of fertilisers comprising urea phosphate
BR8103768A (en) * 1981-06-15 1983-01-18 Inst Pesquisas Tech FERTILIZER PRODUCTION PROCESS
WO1992010443A1 (en) * 1990-12-05 1992-06-25 Transvalor Method for obtaining phospho-nitrogenous products and products thus obtained
US5409516A (en) 1990-12-05 1995-04-25 Transvalor Process for the production of phospho-nitrogenous products and products thus obtained
CN1063674A (en) * 1991-12-30 1992-08-19 郑州工学院 Granular compound fertilizer and technology thereof that the part acidic phosphorus mine single stage method is made

Non-Patent Citations (6)

* Cited by examiner, † Cited by third party
Title
Chem. Zentralblatt, 1963, no.4, page 1405-1406, K. Keiji :"Fabrikation von Harnstoff-Gips und gemischten Lösungen von Phosphorsaüre und Harnstoff" *
Chem. Zentralblatt, no.35, page 330, 1968, abstract nr. 3057, A.W. Frazier et al.:"Monocalciumphosphat-Harnstoff, ein Bestandteil von Mischdüngern" *
CHEMICAL ABSTRACTS, vol. 118, no. 7, 15 February 1993, Columbus, Ohio, US; abstract no. 58864f, SUN, YIZHONG: "Partially oxidized phosphorus ore in one-step manufacture of granular compound fertilizers" page 768; XP000352823 *
CHEMICAL ABSTRACTS, vol. 98, no. 21, 23 May 1983, Columbus, Ohio, US; abstract no. 178170s, W. MARTINS ET AL.: "Fertilizer" page 557; XP002163201 *
GYPSUM & LIME, 1961, Tokio, pages 26 - 31 *
J. AGRIC. FOOD CHEM., vol. 15, no. 2, 1967, pages 345-347 *

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