# US 8,771,621 B2 · Recovery method for a continuous calcium extraction and PCC production

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- Number: US 8,771,621 B2
- Document ID: US8771621B2
- Status: Granted
- Kind: B2
- Application number: 13/723,976
- Filed: 2012-12-21
- Published: 2013-06-27
- Granted: 2014-07-08
- Earliest claimed: 2011-12-21
- Assignees: Corex Materials Corporation
- Applicants: Corex Materials, Inc.
- Inventors: Frank A. Karbarz
- Web page: https://patentgrep.com/patent/US8771621B2

## CPC

- C22B 26/20: Obtaining alkaline earth metals or magnesium
- C01F 11/18: Carbonates
- C09C 1/021: {Calcium carbonates}
- C22B 7/04: Working-up slag
- C01P 2004/39: parallelepiped-like
- C01P 2004/61: Micrometer sized, i.e. from 1-100 micrometer
- C01P 2006/80: Compositional purity
- Y02P 10/20: Recycling
- C22B: PRODUCTION AND REFINING OF METALS (electrolytic C25); PRETREATMENT OF RAW MATERIALS
- C01F: COMPOUNDS OF THE METALS BERYLLIUM, MAGNESIUM, ALUMINIUM, CALCIUM, STRONTIUM, BARIUM, RADIUM, THORIUM, OR OF THE RARE-EARTH METALS (metal hydrides {monoborane, diborane or addition complexes thereof} C01B6/00; salts of oxyacids of halogens C01B11/00; peroxides, salts of peroxyacids C01B15/00; sulfides or polysulfides of magnesium, calcium, strontium, or barium C01B17/42; thiosulfates, dithionites, polythionates C01B17/64; compounds containing selenium or tellurium C01B19/00; binary compounds of nitrogen with metals C01B21/06; azides C01B21/08; {compounds other than ammonia or cyanogen containing nitrogen and non-metals and optionally metals C01B21/082; amides or imides of silicon C01B21/087}; metal {imides or} amides C01B21/092, {C01B21/0923}; nitrites C01B21/50; {compounds of noble gases C01B23/0005}; phosphides C01B25/08; salts of oxyacids of phosphorus C01B25/16; carbides C01B32/90; compounds containing silicon C01B33/00; compounds containing boron C01B35/00; compounds having molecular sieve properties but not having base-exchange properties C01B37/00; compounds having molecular sieve and base-exchange properties, e.g. crystalline zeolites, C01B39/00; cyanides C01C3/08; salts of cyanic acid C01C3/14; salts of cyanamide C01C3/16; thiocyanates C01C3/20; {double sulfates of magnesium with sodium or potassium C01D5/12; with other alkali metals C01D15/00, C01D17/00})
- C09C: TREATMENT OF INORGANIC MATERIALS, OTHER THAN FIBROUS FILLERS, TO ENHANCE THEIR PIGMENTING OR FILLING PROPERTIES (treatment of materials specially adapted to enhance their filling properties in mortars, concrete or artificial stone C04B14/00, C04B18/00, C04B20/00); PREPARATION OF CARBON BLACK {; PREPARATION OF INORGANIC MATERIALS WHICH ARE NO SINGLE CHEMICAL COMPOUNDS AND WHICH ARE MAINLY USED AS PIGMENTS OR FILLERS}
- C01P: INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- Y02P: CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS

## Abstract

A method of mineralizing calcium from industrial waste comprising extracting calcium ions from a suspension of calcium rich granular particles and aqueous ammonium nitrate to form a calcium-rich first fraction and a heavy second fraction. The heavy second fraction is separated from the first fraction and the calcium-rich first fraction is carbonated with a gas comprising carbon dioxide to form a suspension of precipitated calcium carbonate and aqueous ammonium nitrate. The precipitate is separated from the aqueous ammonium nitrate by centrifugal means and the separated heavy second fraction comprises an enriched weight percent of iron.

## Claims

### Claim 1

A method of mineralizing calcium from industrial waste comprising:
a. extracting calcium ions from a suspension of calcium rich particles and aqueous ammonium nitrate, forming a calcium-rich first fraction and a heavy second fraction; wherein said heavy second fraction is separated from said first fraction by centrifugal means;
b. carbonating the calcium-rich first fraction with a gas comprising carbon dioxide, forming a suspension of precipitated calcium carbonate, and aqueous ammonium nitrate, wherein said precipitate is separated from said aqueous ammonium nitrate by centrifugal means; and
wherein said heavy second fraction comprises an enriched weight percent of iron.

### Claim 2 (depends on 1)

The method of claim 1, wherein said gas comprising carbon dioxide is industrial flu gas; industrial waste gas; pure CO2 gas; atmospheric CO2 or combinations thereof.

### Claim 3 (depends on 1)

The method of claim 1, wherein said calcium rich particles may be at least one of ash, fly ash; kiln dust; incinerator waste; waste lime; waste stream calcium oxide; or waste stream calcium hydroxide.

### Claim 4 (depends on 1)

The method of claim 1, wherein said particles are in granular form.

### Claim 5 (depends on 1)

The method of claim 1, wherein said centrifugal means is a horizontal decanter.

### Claim 6 (depends on 1)

The method of claim 1, wherein said method occurs under ambient temperature and ambient pressure.

### Claim 7 (depends on 1)

The method of claim 1, wherein said mineralization occurs in situ of an industrial process.

### Claim 8 (depends on 1)

The method of claim 1, wherein said mineralization occurs proximal to an industrial process.

### Claim 9 (depends on 1)

The method of claim 1 wherein said method is performed on a movable object.

### Claim 10 (depends on 1)

The method of claim 1, wherein said calcium carbonate is crystalline and wherein said crystals comprise at least one of scalenohedral, rhombohedral and prismatic, crystals.

### Claim 11 (depends on 10)

A method of claim 10, wherein said calcium carbonate is at least 95% pure; and is comprised of at least 90% rhombohedral crystals.

### Claim 12 (depends on 11)

The method of claim 11, wherein said crystals are about 5 mm to about 200 microns in size.

### Claim 13 (depends on 1)

The method of claim 1, wherein said method is zero sum energy method.

### Claim 14

A method of enriching the iron content of calcium rich industrial waste the method comprising:
extracting calcium ions from a suspension of starting material of calcium rich industrial waste and aqueous ammonium nitrate, forming a calcium-rich first fraction and a heavy second fraction; wherein said heavy second fraction is separated from said first fraction by centrifugal means; wherein said heavy second fraction comprises an enriched weight percent of iron.

### Claim 15 (depends on 14)

The method of claim 14, further comprising carbonating the calcium-rich first fraction with a gas comprising carbon dioxide, forming a suspension of precipitated calcium carbonate (PCC), wherein said PCC is separated from said aqueous ammonium nitrate by centrifugal means.