# US 10,864,528 B2 · Reducing the need for tailings storage dams in the iron ore industry > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,864,528 B2 - Document ID: US10864528B2 - Status: Granted - Kind: B2 - Application number: 15/843,850 - Filed: 2017-12-15 - Published: 2018-04-26 - Granted: 2020-12-15 - Earliest claimed: 2016-05-11 - Assignees: Anglo American Services (UK) Ltd. - Applicants: Anglo American Services (UK) Ltd - Inventors: Anthony Owen Filmer; Daniel John Alexander - Web page: https://patentgrep.com/patent/US10864528B2 ## CPC - B03D 1/087: {of the sediment, e.g. regrinding} - B02C 23/12: with return of oversize material to crushing or disintegrating zone - B03B 7/00: Combinations of wet processes or apparatus with other processes or apparatus, e.g. for dressing ores or garbage - B03C 1/002: {High gradient magnetic separation (acting directly on the substance being separated B03C1/025; acting on the medium containing the substance being separated B03C1/32)} - B03C 1/30: Combinations with other devices, not otherwise provided for - B03D 1/02: Froth-flotation processes - B03D 1/10: Removing adhering liquid from separated materials (processes or devices capable of general use B01D) - B03D 2203/04: Non-sulfide ores - B03D: FLOTATION; DIFFERENTIAL SEDIMENTATION (sedimentation in general B01D21/00; in combination with other separation of solids B03B; sink-float separation B03B5/28; detergents, soaps C11D) - B02C: CRUSHING, PULVERISING, OR DISINTEGRATING IN GENERAL; MILLING GRAIN ({household tools and machines for pulverising foodstuffs, e.g. coffee and spice mills A47J42/00; pharmaceutical mortars A61J3/02; mechanical processing of refuse and garbage B03B9/06; dressing mould materials by grinding B22C5/04}; obtaining metallic powder by crushing, grinding or milling B22F9/04; {recovery of plastics by disintegrating B29B17/00; crushing raw materials in starch making C08B30/02; beaters for papermaking D21D1/02; crushing devices specially for transport in mines E21F13/002; slag crushing devices F23J1/00; fuel milling devices in combustion apparatus F23K1/00; household devices for crushing coal F24B15/02; ice disintegrating devices F25C5/02}) - B03B: SEPARATING SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS - B03C: MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS (separating isotopes B01D59/00; combinations of magnetic or electrostatic separation with separation of solids by other means B03B, B07B) ## Abstract THIS invention relates to an integrated process for recovering the valuable iron fraction from low grade iron ore, including the steps of: comminution 14 and classification 36/39 to obtain a classified fraction suitable for coarse flotation and classified fraction suitable for fine beneficiation; subjecting the fraction suitable for coarse flotation to coarse flotation 40 to obtain an intermediate iron concentrate 42 and a coarse sand residue 44; grinding the intermediate concentrate to a size suitable for fine beneficiation; and subjecting the fractions suitable for fine beneficiation to fine beneficiation 46 and obtaining a final iron concentrate 48 and a fine tailings 50. ## Claims ### Claim 1 An integrated process for recovering the valuable iron fraction from low grade iron ore, including the steps of: a) comminution of the iron ore in a comminution device, b) classification of the comminuted iron ore to obtain a classified fraction suitable for coarse flotation with a particle size range from 100 micron up to 1000 micron and classified fraction suitable for fine beneficiation with a particle size of less than 100 micron; c) subjecting the fraction suitable for coarse flotation to coarse flotation to obtain an intermediate iron concentrate and a coarse sand residue with a particle size range from 100 micron up to 1000 micron; d) grinding the intermediate concentrate to a size suitable for fine beneficiation with a particle size of less than 100 micron; and e) subjecting the fractions suitable for fine beneficiation from steps b) and d) to fine beneficiation and obtaining a final iron concentrate and a fine tailings; wherein: the coarse sand residue from step c) is dewatered to less than 20 percent water by weight, and the dewatered coarse residue is dry-stacked separately from the fine tailings. ### Claim 2 (depends on 1) The process claimed in claim 1, wherein the comminution of the ore at step a) is carried out in closed circuit with classification at step b) arranged such that feed to coarse flotation is in a size range at which at least 40% of a gangue is predominantly liberated. ### Claim 3 (depends on 2) The process claimed in claim 2, wherein at least 60% of the gangue is predominantly liberated. ### Claim 4 (depends on 3) The process claimed in claim 3, wherein more than 60% of the gangue is predominantly liberated. ### Claim 5 (depends on 1) The process claimed in claim 1, wherein the classified faction suitable for coarse flotation is within the size range from 100 micron to 600 micron. ### Claim 6 (depends on 1) The process claimed in claim 1, wherein an oversize fraction from step b) is recycled to comminution step a). ### Claim 7 (depends on 1) The process claimed in claim 1, wherein the intermediate concentrate from coarse flotation step c) is directed to a regrind in step e). ### Claim 8 (depends on 1) The process claimed in claim 1, wherein the fine beneficiation is fine flotation or magnetic separation. ### Claim 9 (depends on 8) The process claimed in claim 8, wherein the fine beneficiation is fine flotation.