# US 11,028,025 B2 · Pelletising process using starch > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,028,025 B2 - Document ID: US11028025B2 - Status: Granted - Kind: B2 - Application number: 15/515,995 - Filed: 2015-08-27 - Published: 2017-10-26 - Granted: 2021-06-08 - Earliest claimed: 2014-09-30 - Assignees: York Potash Ltd - Applicants: York Potash Ltd - Inventors: Steve Farnworth; Mike Evans; Jim Evans - Web page: https://patentgrep.com/patent/US11028025B2 ## CPC - C05D 1/00: Fertilisers containing potassium (C05D7/00 takes precedence) - B01F 23/60: Mixing solids with solids - B01F 33/82: Combinations of dissimilar mixers - B01F 35/90: Heating or cooling systems - B01J 2/20: by expressing the material, e.g. through sieves and fragmenting the extruded length - B01J 2/28: using special binding agents - C05D 1/005: {post-treatment} - C05G 5/12: Granules or flakes - C05G 5/40: Fertilisers incorporated into a matrix - B01F 2035/99: {Heating} - C05D: INORGANIC FERTILISERS NOT COVERED BY SUBCLASSES C05B, C05C; FERTILISERS PRODUCING CARBON DIOXIDE - B01F: MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING (mixing paints B44D3/06) - B01J: CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS - 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 ## Abstract A method for manufacturing a pelletised mineral product, the method comprising: in a first mixing step, forming a first mixture by mixing the evaporite mineral with non-gelatinised starch under conditions that are insufficient to substantially gelatinise the starch; in a second mixing step, forming a second mixture by mixing the first mixture under conditions that are sufficient to substantially gelatinise the starch comprised within the first mixture; and forming the second mixture into pellets. ## Claims ### Claim 1 A method for manufacturing a pelletised mineral product, the method comprising: in a first mixing step, forming a first mixture by mixing polyhalite with non-gelatinised starch under conditions that are insufficient to substantially gelatinise the starch; in a second mixing step, forming a second mixture by mixing the first mixture under conditions that are sufficient to substantially gelatinise the starch comprised within the first mixture; and forming the second mixture into pellets; wherein the pellets comprise greater than 75% by weight polyhalite. ### Claim 2 (depends on 1) A method as claimed in claim 1, wherein the first mixing step is performed substantially in the absence of free water. ### Claim 3 (depends on 2) A method as claimed in claim 2, wherein the second mixing step is performed in the presence of free water. ### Claim 4 (depends on 3) A method as claimed in claim 3, comprising adding water to the first mixture during the second mixing step. ### Claim 5 (depends on 4) A method as claimed in claim 4, wherein the water is added in the form of steam. ### Claim 6 (depends on 4) A method as claimed in claim 4, wherein the water is added in the form of vapour. ### Claim 7 (depends on 1) A method as claimed in claim 1, wherein the second mixing step is performed in the presence of free water. ### Claim 8 (depends on 7) A method as claimed in claim 7, comprising adding water to the first mixture during the second mixing step. ### Claim 9 (depends on 8) A method as claimed in claim 8, wherein the water is added in the form of steam. ### Claim 10 (depends on 9) A method as claimed in claim 9, wherein the second mixing step is performed by means of a mixer having a mixing chamber and the steam is injected into the mixing chamber. ### Claim 11 (depends on 10) A method as claimed in claim 10, wherein the mixing chamber is substantially enclosed. ### Claim 12 (depends on 8) A method as claimed in claim 8, wherein the water is added in the form of vapour. ### Claim 13 (depends on 12) A method as claimed in claim 12, wherein the second mixing step is performed by means of a mixer having a mixing chamber and the vapour is injected into the mixing chamber. ### Claim 14 (depends on 1) A method as claimed in claim 1, wherein the second mixing step comprises applying heat to the first mixture. ### Claim 15 (depends on 1) A method as claimed in claim 1, wherein the first mixing step is performed in at least one first mixer and the second mixing step is performed in a second mixer different from the first mixer. ### Claim 16 (depends on 1) A method as claimed in claim 1, wherein the step of forming the second mixture into pellets comprises extruding the second mixture. ### Claim 17 (depends on 1) A method as claimed in claim 1, wherein the step of forming the second mixture into pellets comprises extruding the second mixture and tumbling the extrudate in a rotary dryer. ### Claim 18 (depends on 1) A method as claimed in claim 1, wherein the first mixing step comprises mixing the polyhalite in particulate form. ### Claim 19 (depends on 18) A method as claimed in claim 18, wherein the particulate form has an average grain size in the range from 50 to 500 μm. ### Claim 20 (depends on 1) A method as claimed in claim 1, wherein the first mixing step comprises mixing the starch in particulate form. ### Claim 21 (depends on 20) A method as claimed in claim 20, wherein the average grain size of the starch is in the range from 300 to 700 μm.