SULPHUR-CONTAINING FERTILIZERS AND PROCESS FOR THE PREPARATION THEREOF

• US 20110302973A1
• Filed: 01/29/2010
• Published: 12/15/2011
• Est. Priority Date: 01/29/2009
• Status: Active Grant

• Current Assignee: Shell USA Incorporated (Shell Plc)
• Original Assignee: Shell Oil Company (Shell Plc)
• Inventors: Antens, Jany Birgitta Maria, Reynhout, Marinus Johannes, Verbist, Guy Lode Magda Maria, Ashtekar, Sunil, Garcia Martinez, Rafael Alberto, Lambert, Reginald, O'Brien, Jason Trevor, Woodruffe, John
• Granted Patent: US 8,668,759 B2
• Time in Patent Office: Days
• US Class Current: 71/23
• CPC Class Codes: C05B 1/00 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
• CPC Class Codes: C05B 7/00 Fertilisers based essentially on alkali or ammonium orthophosphates C05B11/00 takes precedence
• CPC Class Codes: C05D 9/00 Other inorganic fertilisers
• CPC Class Codes: C05G 3/50 Surfactants; Emulsifiers
• CPC Class Codes: C05G 5/12 Granules or flakes

Abstract

Process for the manufacture of sulphur-containing fertilizer compositions, comprising the steps of: a} providing a slurry of at least one phosphate-based fertilizer material selected from the group consisting of ammonium phosphates, ammonium phosphate based nitrogen-phosphorus-potassium (NPK) compounds, super phosphates and partially acidulated phosphate rocks; b) bringing said slurry into contact with at least one anionic surfactant and elemental sulphur; c) introducing the mixture obtained in step b} into a granulator unit in order to obtain granules of the fertilizer composition, wherein the at least one phosphate-based fertilizer material is present in an amount in the range of at least 50 wt. %, the elemental sulphur is present in an amount in the range of from 1 to 25 wt. % and the anionic surfactant is present in an amount in the range of from 0.001 to 3 wt. % based on the overall weight of the fertilizer composition. The present invention also provides a fertilizer composition.

Claims

1. A process for the manufacture of sulphur-containing fertilizer compositions, said process comprising the steps of:

a) providing a slurry of at least one phosphate-based fertilizer material selected from the group consisting of ammonium phosphates, ammonium phosphate based nitrogen-phosphorus-potassium (NPK) compounds, super phosphates and partially acidulated phosphate rocks;

b) bringing said slurry into contact with at least one anionic surfactant and elemental sulphur; and

c) introducing the mixture obtained in step b) into a granulator unit in order to obtain granules of the fertilizer composition,

wherein the at least one phosphate-based fertilizer material is present in an amount in the range of at least 50 wt. %, the elemental sulfur is present in an amount in the range of from 1 to 25 wt. % and the at least one anionic surfactant is present in an amount in the range of from 0.001 to 3 wt. % based on the overall weight of the fertilizer composition.

2. A process as claimed in claim 1, wherein elemental sulphur comprises molten sulphur.

3. A process as claimed in claim 1, wherein the at least one anionic surfactant comprises a lignosulphonate.

4. A process as claimed in claim 1, wherein the at least one anionic surfactant is present in an amount in the range of from 0.05 to 3 wt. % with respect to the weight of the overall fertilizer composition.

9. Use of an anionic surfactant for reducing the elemental sulphur content in process dust generated in a process as defined in claim 1.

5. A fertilizer composition comprising:

a) elemental sulphur in an amount in the range of from 1 to 25 wt. %, based on the overall weight of the fertilizer composition;

b) at least one phosphate-based fertilizer material selected from the group consisting of ammonium phosphates, ammonium phosphate based nitrogen-phosphorus-potassium (NPK) compounds, super phosphates and partially acidulated phosphate rocks present in an amount of at least 50 wt. %, based on the overall weight of the fertilizer composition; and

c) at least one anionic surfactant present in an amount in the range of from 0.001 to 3 wt. % based on the overall weight of the fertilizer composition,

wherein the at least one anionic surfactant is dispersed throughout the fertilizer composition.

6. A fertilizer composition as claimed in claim 5, wherein the at least one anionic surfactant comprises a lignosulphonate.

7. A fertilizer composition as claimed in claim 6, wherein the at least one anionic surfactant comprises a lignosulphonate selected from the group consisting of alkali metal salts of lignosulphonic acid, alkaline earth metal salts of lignosulphonic acid and ammonium salts of lignosulphonic acid.

8. A fertilizer composition as claimed in claim 5, wherein the at least one anionic surfactant is present in an amount in the range of from 0.05 to 3 wt. % with respect to the weight of the overall fertilizer composition.