US3734707A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for reducing emission of dust by granular fertilizer compositions
Assignee: Royster Co
•
Filing: 1970-10-22
•
Granted: 1973-05-22
•
Expires: 1990-10-22
Abstract
Abstract Emission of air-borne particulates by granular fertilizer compositions upon being moved or handled is substantially reduced by spraying the granules with aqueous solutions of nitrogencontaining salts at the end of the cooling phase of the manufacturing procedure.
Inventors
- 👤 J Seymour
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 20:36
CPC Classifications
C; C05; C05B; C05B7/00; B; B01; B01J; B01J2/00; B01J2/28; C05G; C05G3/00; C05G3/20; C05G5/00; C05G5/30
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
28 words
The process according to claim 1, wherein the aqueous solution of a nitrogen-containing salt is sprayed upon the fertilizer particulates at the discharge end of the air cooler.
Claim 2
Dependent Claim
17 words
The process according to claim 1 in which the aqueous solution contains ammonium orthophosphate and ammonium polyphosphate.
Claim 3
Dependent Claim
38 words
The process according to claim 3 in which the nitrogen-containing salts are present in the solution in amounts such that the total nitrogen content of the dissolved salts is at least 10 peRcent by weight of the solution.
Claim 4
Dependent Claim
33 words
The process according to claim 4 in which the aqueous solution of nitrogen-containing salts is applied at the rate of about 8 to 10 pounds of solution per ton of granulated fertilizer composition.
Claim 5
Dependent Claim
26 words
The process according to claim 1 in which the aqueous solution contains about 44 percent by weight ammonium nitrate and about 35 percent by weight urea.
Claim 6
Independent Claim
70 words
The method of reducing the concentration of fertilizer dust in the atmosphere by the manufacture of fertilizer particulates resistant to emitting air-borne dust upon attrition, which comprises heat-drying ammoniated phosphoric acid, air-cooling the dried phosphatic fertilizer, and spraying the air-cooled fertilizer particulates with an aqueous solution of a nitrogen-containing salt to create an interparticle salt bridge between air-borne dust particles, and between air-borne dust particles and larger than air-borne particles.
Claim 7
Dependent Claim
20 words
The process according to claim 7 in which the aqueous solution contains a mixture of ammonium orthophosphate and ammonium polyphosphate.
Claim 8
Dependent Claim
38 words
The process according to claim 8 in which the nitrogen-containing salts are present in the solution in amounts such that the total nitrogen content of the dissolved salts is at least 10 percent by weight of the solution.
Claim 9
Dependent Claim
33 words
The process according to claim 9 in which the aqueous solution of nitrogen-containing fertilizers is applied at the rate of about 0.5 to 25 pounds of solution per ton of granulated fertilizer composition.
Claim 10
Dependent Claim
26 words
The process according to claim 7 in which the aqueous solution contains about 44 percent by weight ammonium nitrate and about 35 percent by weight urea.
Claim 11
Dependent Claim
77 words
In the manufacture of fertilizer compositions, wherein fertilizer particulates are heat dried, size classified and air cooled, the process for rendering the fertilizer compositions resistant to emitting air-borne dust upon attrition, which comprises spraying the fertilizer particulates with an aqueous solution of a nitrogen-containing fertilizer at the end of the air cooling phase of the manufacturing procedure to create an interparticle salt bridge between air-borne dust particles, and between air-borne dust particles and larger than air-borne particles.
Claim 12
Dependent Claim
28 words
The process according to claim 12, wherein the aqueous solution of a nitrogen-containing fertilizer is sprayed upon the fertilizer particulates at the discharge end of the air cooler.
Claim 13
Dependent Claim
17 words
The process according to claim 12 in which the aqueous solution contains ammonium orthophosphate and ammonium polyphosphate.
Claim 14
Dependent Claim
38 words
The process according to claim 14 in which the nitrogen-containing fertilizers are present in the solution in amounts such that the total nitrogen content of the dissolved fertilizers is at least 10 percent by weight of the solution.
Claim 15
Dependent Claim
33 words
The process according to claim 15 in which the aqueous solution of nitrogen-containing fertilizers is applied at the rate of about 8 to 10 pounds of solution per ton of granulated fertilizer composition.
Claim 16
Dependent Claim
26 words
The process according to claim 12 in which the aqueous solution contains about 44 percent by weight ammonium nitrate and about 35 percent by weight urea.
Claim 17
Independent Claim
50 words
The method for reducing the concentration of fertilizer dust in the atmosphere by the manufacture of fertilizer particulates resistant to emitting air-borne dust upon attrition, which comprises heat-drying ammoniated phosphoric acid, air-cooling the dried phosphatic fertilizer, and spraying the air-cooled fertilizer particulates with an aqueous solution of a nitrogen-containing fertilizer.
Claim 18
Dependent Claim
20 words
The process according to claim 18 in which the aqueous solution contains a mixture of ammonium orthophosphate and ammonium polyphosphate.
Claim 19
Dependent Claim
37 words
The process according to claim 19 in which the nitrogen-containing fertilizers are present in the solution in amounts such that the total content of the dissolved fertilizers is at least 10 percent bY weight of the solution.
Claim 20
Dependent Claim
33 words
The process according to claim 20 in which the aqueous solution of nitrogen-containing fertilizers is applied at the rate of about 0.5 to 25 pounds of solution per ton of granulated fertilizer composition.
Claim 21
Dependent Claim
26 words
The process according to claim 18 in which the aqueous solution contains about 44 percent by weight ammonium nitrate and about 35 percent by weight urea.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-05-21 | 1976-11-20 | 1977-05-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-05-21 | 1980-11-20 | 1981-05-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-05-21 | 1984-11-20 | 1985-05-22 | $7700.00 | Window Closed / Lapsed |