# US 4,394,150 A · Sulphur-clay prills > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 4,394,150 A - Document ID: US4394150A - Status: Granted - Kind: A - Application number: 06/229,642 - Filed: 1981-01-29 - Granted: 1983-07-19 - Earliest claimed: 1980-02-29 - Assignees: Canadian Superior Oil Ltd. - Inventors: Barney D. Garrison, Jr.; Barry S. Marjanovich - Web page: https://patentgrep.com/patent/US4394150A ## CPC - C05G 5/36: {layered or coated with sulfur} - C05D 9/00: Other inorganic fertilisers - Y10S 71/903: Soil conditioner - Y10S 71/904: Carrier - C05G: MIXTURES OF FERTILISERS COVERED INDIVIDUALLY BY DIFFERENT SUBCLASSES OF CLASS C05; MIXTURES OF ONE OR MORE FERTILISERS WITH MATERIALS NOT HAVING A SPECIFIC FERTILISING ACTIVITY, e.g. PESTICIDES, SOIL-CONDITIONERS, WETTING AGENTS (organic fertilisers containing added bacterial cultures, mycelia, or the like C05F11/08; organic fertilisers containing plant vitamins or hormones C05F11/10); FERTILISERS CHARACTERISED BY THEIR FORM - C05D: INORGANIC FERTILISERS NOT COVERED BY SUBCLASSES C05B, C05C; FERTILISERS PRODUCING CARBON DIOXIDE - Y10S: TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS ## Abstract Substantially spherical, water-degradable, sulphur clay particles or prills are provided; the particles are formed by passing a mixture of molten sulphur and a particulate swelling clay through a plurality of orifices and into an aqueous solution of a water soluble electrolyte salt, maintained at a temperature effective to cool the mixture below its solidification temperature. An improved apparatus is also provided in which a high constant static head of molten material is let down to a low static head whereby molten material at low velocity falls under gravity into the aqueous electrolyte salt solution. ## Claims ### Claim 1 A process for producing substantially spherical, water degradable, sulphur-clay particles comprising: passing at least one stream of a mixture comprising molten sulphur and a particulate swelling clay into an aqueous solution of a water soluble electrolyte salt, said solution comprising about 5 to 15%, by weight, of said salt and about 85 to 95%, by weight, of water, maintaining said solution at a temperature effective to cool said mixture below its solidification temperature, allowing the surface tension of the molten sulphur to break up said stream in said solution to form substantially spherical droplets and allowing said droplets to cool and solidify in said solution to form said substantially spherical particles, withdrawing said particles from said solution and drying said particles. ### Claim 2 (depends on 1) A process according to claim 1, wherein said electrolyte salt is an inorganic salt. ### Claim 3 (depends on 2) A process according to claim 2, wherein said solution is maintained at a temperature of about 140.degree. F. to about 170.degree. F. ### Claim 4 (depends on 3) A process according to claim 3, wherein said swelling clay is present in said mixture in an amount effective to produce sulphur-clay particles containing about 7 to about 12%, by weight of said swelling clay. ### Claim 5 (depends on 4) A process according to claim 4, wherein said electrolyte salt is a water soluble halide, sulphate, nitrate, carbonate, phosphate or polyphosphate of potassium, sodium, calcium or ammonium. ### Claim 6 (depends on 4) A process according to claim 4, wherein said salt is a strong electrolyte which is agronomically, agriculturally and horticulturally acceptable. ### Claim 7 (depends on 4) A process according to claim 4, wherein said mixture of said stream is at a temperature of about 250.degree. F. to about 270.degree. F. ### Claim 8 (depends on 1) A process according to claim 1, wherein said swelling clay is present in said mixture in an amount effective to produce spherical sulphur-clay particles containing about 7 to about 12%, by weight of said swelling clay. ### Claim 9 (depends on 8) A process according to claim 8, wherein said electrolyte salt is a strong electrolyte. ### Claim 10 A process for producing water-degradable, sulphur-clay prills comprising: forming a high static head of a mixture comprising molten sulphur and a particulate swelling clay, allowing said mixture to fall through a plurality of orifices to form a low static head of the mixture, feeding the mixture in the low static head in a plurality of continuous streams of circular cross-section into an aqueous solution of a water soluble electrolyte salt, said solution comprising about 5 to 15%, by weight, of said salt and about 85 to 95%, by weight, of water and being maintained at a temperature effective to cool said mixture below its solidification temperature, allowing the surface tension of the molten sulphur to break up said streams in said solution to form substantially spherical droplets and allowing said droplets to cool and solidify in said solution to form said prills, withdrawing the prills from said solution and drying said prills, said swelling clay being present in said mixture in an amount to provide a content of clay in said prills effective to render the prills water degradable. ### Claim 11 (depends on 10) A process according to claim 10, wherein said salt is an inorganic salt in a concentration of about 5 to about 15%, by weight and said solution is maintained at a temperature of about 140.degree. F. to about 170.degree. F. ### Claim 12 (depends on 11) A process according to claim 11, wherein said mixture in said high static head is maintained at a temperature of about 250.degree. F. to about 270.degree. F. ### Claim 13 (depends on 12) A process according to claim 12, wherein said continuous streams have a diameter of 1/16 to 3/32 inches and said high static head has a depth from 40 to 50 times the depth of the low static head. ### Claim 14 In a method of forming solid, substantially spherical particles from a molten, solidifiable material, comprising feeding the molten material in a plurality of continuous streams into a forming medium effective to cool said molten material below its solidification temperature to form solid, substantially spherical particles, the improvement wherein said molten material is allowed to fall from a constant high static head through a first plurality of orifices to form a constant low static head of said molten material above said forming medium, said low static head being vertically below said high static head, and allowing said molten material to fall through a second plurality of orifices from said constant low static head in said plurality of continuous streams into said forming medium, said high static head having a depth of 40 to 50 times the depth of the low static head. ### Claim 15 (depends on 14) A method according to claim 14, wherein said orifices of said second plurality have a diameter of 1/16 to 3/32 inches, and the individual orifices of said first plurality have a diameter greater than the orifices of the second plurality, the second plurality being greater than the first plurality such that the total cross-sectional area of orifices in the second plurality is greater than that in the first plurality. ### Claim 16 (depends on 14) A method according to claim 14, wherein said low static head has a depth of not more than about 0.5 inches. ### Claim 17 (depends on 14) A method according to claim 14, wherein said molten material is allowed to fall from said high static head to a distribution means in which a low static head of molten material is formed, said molten material being allowed to fall from said low static head in said distribution means through a third plurality of orifices to form said constant low static head above said forming medium, the low static head above said forming medium being lower than the low static head in said distribution means. ### Claim 18 (depends on 17) A method according to claim 17, wherein said constant low static head has a depth of about 0.1 to about 0.5 inches. ### Claim 19 (depends on 14) A method according to claim 14, wherein said molten material is allowed to fall from said high static head to a distribution means in which a low static head of molten material is formed, said molten material being allowed to fall from said low static head in said distribution means through a third plurality of orifices to form said constant low static head above said forming medium, the low static head above said forming medium being lower than the low static head in said distribution means; and said orifices of said second plurality have a diameter of 1/16 to 3/32 inches, and the individual orifices of said first plurality have a diameter greater than the orifices of the second plurality, the second plurality being greater than the first plurality such that the total cross-sectional area of orifices in the second plurality is greater than that in the first plurality; said orifices of said third plurality having a cross-sectional area smaller than the orifices of said first plurality and greater than the orifices of said second plurality, the total cross-sectional area of the orifices of said third plurality being greater than that of said first plurality and less than that of said second plurality. ### Claim 20 (depends on 14) A method according to claim 14, wherein said orifices of said second plurality have a diameter of 1/16 to 3/32 inches and are spaced at least 3/4 inches apart, said constant low static head being maintained at a spacing of 2 to 6 inches from the surface of the forming medium. ### Claim 21 (depends on 20) A method according to claim 20, wherein said molten material is allowed to fall from said high static head to a distribution means in which a low static head of molten material is formed, said molten material being allowed to fall from said low static head in said distribution means through a third plurality of orifices to form said constant low static head above said forming medium, the low static head above said forming medium being lower than the low static head in said distribution means. ### Claim 22 (depends on 10) A process according to claim 10, wherein said high static head is a constant head and said mixture falls through said plurality of orifices said orifices defining a first plurality, to form a constant low static head of said molten material above said aqueous solution and said mixture is allowed to fall through a second plurality of orifices from said constant low static head in said plurality of continuous streams into said aqueous solution. ### Claim 23 (depends on 22) A method according to claim 22, wherein said high static head has a depth of 40 to 50 times the depth of said low static head. ### Claim 24 (depends on 23) A method according to claim 23, wherein said orifices of said second plurality have a diameter of 1/16 to 3/32 inches, and the individual orifices of said first plurality have a diameter greater than the orifices of the second plurality, the second plurality being greater than the first plurality such that the total cross-sectional area of orifices in the second plurality is greater than that in the first plurality. ### Claim 25 (depends on 24) A process according to claim 24, wherein said low static head has a depth of not more than about 0.5 inches and is maintained at a spacing of 2 to 6 inches from the surface of said aqueous solution. ### Claim 26 A process for producing water-degradable, sulphur-clay prills comprising: forming a high static head of a mixture comprising molten sulphur and a particulate swelling clay, said swelling clay being present in said mixture in an amount effective to produce sulphur-clay prills containing about 7 to 12%, by weight, of said swelling clay, allowing said mixture to fall from said high static head through a first plurality of orifices to a distribution means in which an intermediate static head is formed, said intermediate static head being vertically below said high static head, allowing said mixture to fall from said distribution means through a second plurality of orifices to form a low static head of the mixture at a temperature of about 250.degree. F. to about 270.degree. F., said low static head having a depth of not more than about 0.5 inches, and said high static head having a depth of 40 to 50 times the depth of the low static head, and said low static head being of lower depth than said intermediate static head, said low static head being vertically below said intermediate static head, allowing the mixture in the low static head to fall from the low static head through a third plurality of orifices in a plurality of continuous streams of circular cross-section into an aqueous solution of a water soluble, inorganic electrolyte salt, said solution having an upper surface spaced 2 to 6 inches below said low static head, and consisting essentially of about 5 to 15%, by weight, of said salt and about 85 to 95%, by weight, of water, said solution being maintained in a quiescent state at a temperature of about 140.degree. F. to about 170.degree. F., allowing the surface tension of the molten sulphur to break up said streams in said solution to form substantially spherical droplets, and allowing said droplets to cool and solidify in said solution to form prills, withdrawing the prills from said solution, drying said prills and recovering said prills as sulphur-clay prills having a smooth, hard, substantially spherical surface, and containing 88 to 93%, elemental sulphur and 7 to 12% swelling clay, in weight percent, with an internal moisture content, in weight percent of 0.02 to 0.17 and a surface moisture content of 0 to 1.5%, the orifices of said first plurality having a diameter greater than the orifices of said third plurality, the third plurality being greater than the first plurality such that the total cross sectional area of orifices in the third plurality is greater than in the first plurality, said orifices of said second plurality having a cross-sectional area smaller than the orifices of said first plurality and greater than the orifices of said third plurality, the total cross-sectional area of the orifices of said second plurality being greater than that of said first plurality and less than that of said third plurality, said orifices of said third plurality having a diameter of 1/16 to 3/32 inches and being spaced at least 3/4 inches apart.