Symbole du gouvernement du Canada


Numéro de document de brevet: 2006751

(54) Titre anglais: HOMOGENEOUS GRANULAR NITROGEN FERTILIZER

(54) Titre français: ENGRAIS AZOTE EN GRANULES HOMOGENES


Revendications:

Nota : Les revendications sont présentées dans la langue officielle dans laquelle elles ont été soumises.


WHAT IS CAIMED:
1. A homogeneous granulated fertilizer composition
comprising as components urea, ammonium thiosulfate and
dicyandiamide, the foregoing components being in a homogeneous
blend by said components being formed into granules from a
melt of said urea component.
2. A homogeneous fertilizer composition as in claim 1
wherein said granules contain a conditioning agent.
3. A homogeneous fertilizer composition as in claim 2
wherein said conditioning agent is selected from the group
consisting of urea formaldehyde and calcium lignosulfonate.
4. A homogeneous fertilizer composition as in claim 2
wherein said granules contain a dye.
5. A homogeneous fertilizer composition as in claim 1
wherein said granules have a particle size of from about 0.84
millimeters to 4.76 millimeters.
6. A homogeneous fertilizer composition as in claim 1
wherein said urea is present in an amount of about 90 percent
to 98 percent by weight, said ammonium thiosulfate is present
in an amount of about 0.4 percent to 1.0 percent by weight,
and said dicyandiamide is present in an amount of about 1.4
percent to 3.0 percent by weight.
7. A homogeneous fertilizer composition as in claim 1
wherein said composition contains from about 0.3 to 1 percent
by weight of P205.
8. A homogeneous fertilizer composition as in claim 1
wherein said P205 is present as an ammonium phosphate.


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9. A method of enhancing the growth of plants by
applying to the soil a homogeneous granulated fertilizer
composition comprising as components urea, ammonium
thiosulfate and dicyandiamide, the foregoing components being
in a homogeneous blend by said components being formed into
granules from a melt of said urea component.
10. A method as in claim 9 wherein said granules contain
a conditioning agent.
11. A method as in claim 10 wherein said conditioning
agent is selected from the group consisting of urea
formaldehyde and calcium lignosulfonate.
12. A method as in claim 9 wherein said granules contain
dye.
13. A method as in claim 9 wherein said urea is present
in an amount of about 90 percent to 98 percent by weight, said
ammonium thiosulfate is present in an amount of about 0.4
percent to 1.0 percent by weight and said dicyandiamide is
present in an amount of about 1.4 to about 3.0 percent by
weight.
14. A method as in claim 13 wherein phosphate is present
in an amount of about 0.3 percent to 1.0 percent by weight.
15. A method as in claim 9 wherein said granules are in
the particle size range of about 0.84 millimeters to about
4.76 millimeters.
16. A method for producing a homogeneous granulated
fertilizer composition comprising:
(a) providing urea in a molten condition and adding





dicyandiamide and ammonium thiosulfate to said molten urea;
(b) removing at least some of the contained
moisture from the molten urea containing dicyandiamide and
ammonium thiosulfate dissolved therein; and
(c) forming said molten urea containing
dicyandiamide and ammonium thiosulfate dissolved therein into
granules.
17. A method as in claim 16 wherein said ammonium
thiosulfate is added to the molten urea as an aqueous
solution.
18. The method as in claim 16 wherein said dicyandiamide
and ammonium thiosulfate are added to a portion of molten urea
which is then added to a larger portion of molten urea.
19. The method as in claim 16 wherein said molten urea
has a moisture content of about 2 to 8 percent by weight when
dicyandiamide and ammonium thiosulfate are added thereto.
20. A method as in claim 16 wherein a conditioning agent
is added to said molten urea when said molten urea has a
moisture content of greater than about 4 percent by weight.
21. A method as in claim 16 wherein a source of
phosphate is added to said molten urea along with the
dicyandiamide and ammonium thiosulfate.
22. A method as in claim 21 wherein said source of
phosphate is an ammonium phosphate.
23. A method as in claim 16 wherein said granular
fertilizer as produced contains from about 94 percent to 98
percent by weight urea, from about 1.4 percent to about 3.0



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percent by weight of dicyandiamide, and from about 0.4 percent
to about 1.0 percent by weight of ammonium thiosulfate and
less than about 1 percent by weight of moisture.
24. A method as in claim 23 wherein said granular
fertilizer contains from about 0.3 percent to about 1 percent
by weight of phosphate.
25. A method as in claim 23 wherein said granular
fertilizer contains from about 0.2 percent to about 1 percent
by weight of conditioning agent.
26. A method as in claim 16 wherein said granules have a
particle size of about 0.84 millimeters to about 4.76
millimeters.




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