Process to make calcium oxide or ordinary portland cement from calcium bearing rocks and minerals

Patent metadata

Field	Value
Publication number	US-2022411328-A1
Application number	US-202217894621-A
Country	US
Kind code	A1
Filing date	Aug 24, 2022
Priority date	Aug 13, 2019
Publication date	Dec 29, 2022
Grant date	—

Abstract

Aspects of the invention include a method of producing a cement material comprising step of: first reacting a calcium-bearing starting material with a first acid to produce an aqueous first calcium salt; second reacting the aqueous first calcium salt with a second acid to produce a solid second calcium salt; wherein the second acid is different from the first acid and the second calcium salt is different from the first calcium salt; and thermally treating the second calcium salt to produce a first cement material. Preferably, but not necessarily, during the second reacting step, reaction between the first calcium salt and the second acid regenerates the first acid.

First claim

We claim:

1 . A method comprising:
first reacting a calcium-bearing starting material with a first acid to produce a first aqueous fraction comprising an aqueous first calcium salt and a first solid fraction comprising one or more solid byproducts; wherein:
the calcium-bearing starting material has a chemical composition comprising a plurality of metal elements including at least Ca and Si;
the one or more solid byproducts comprises a silicon compound;
separating the first aqueous fraction from the first solid fraction; and treating the first calcium salt to produce a first cement material.

2 . The method of claim 1 , wherein the calcium-bearing starting material comprises at least one multinary metal oxide material having a composition comprising Ca and at least one other metal element selected from the group consisting of Al, Si, Fe, Mn, and Mg.

3 . The method of claim 1 , wherein the calcium-bearing starting material comprises at least one natural rock or mineral comprising basalt, igneous appetites, wollastonite, anorthosite, montmorillonite, bentonite, calcium-containing feldspar, anorthite, diopside, pyroxene, pyroxenite, mafurite, kamafurite, clinopyroxene, colemonite, grossular, augite, pigeonite, margarite, calcium serpentine, garnet, scheilite, skarn, limestone, natural gypsum, appetite, fluorapatite, or any combination of these.

4 . The method of claim 3 , wherein the calcium-bearing starting material comprises at least one natural rock or mineral comprising basalt, igneous appetites, wollastonite, anorthosite, montmorillonite, bentonite, calcium-containing feldspar, anorthite, diopside, pyroxene, pyroxenite, mafurite, kamafurite, clinopyroxene, colemonite, grossular, augite, pigeonite, margarite, calcium serpentine, garnet, scheilite, skarn, natural gypsum, appetite, fluorapatite, or any combination of these.

5 . The method of claim 1 , wherein the calcium-bearing starting material is other than CaCO 3 or comprises a material other than CaCO 3 .

6 . The method of claim 1 , wherein the first acid comprises hydrochloric acid.

7 . The method of claim 6 , further comprising regenerating the hydrochloric acid.

8 . The method of claim 1 , wherein the first reacting step is performed at a temperature of at least 50° C.

9 . The method of claim 1 , wherein the first calcium salt is calcium chloride.

10 . The method of claim 1 , wherein the silicon compound comprises SiO 2 .

11 . The method of claim 1 , wherein the silicon compound comprises >90 dry wt % purity SiO 2 .

12 . The method of claim 1 , wherein the silicon compound comprises silica fume.

13 . The method of claim 1 , further comprising: forming and isolating oxides of Al, oxides of Mg, and/or oxides of Fe.

14 . The method of claim 1 , wherein treating the first calcium salt to produce a first cement material comprises thermally treating the first calcium salt in the presence of water to produce the first cement material.

15 . The method of claim 14 , wherein thermally treating the first calcium salt in the presence of water regenerates the first acid.

16 . The method of claim 1 , wherein thermally treating the first calcium salt to produce a first cement material further comprises adding one or more additives to the first calcium salt prior to treating.

17 . The method of claim 16 , wherein the one or more additives comprise a byproduct of the first reacting step and/or are formed from the one or more byproducts of the first reacting step.

18 . The method of claim 16 , wherein the one or more additives comprise a silicon compound.

19 . The method of claim 1 , further comprising treating the first cement material to form a composite cement material.

20 . The method of claim 19 , wherein forming the composite cement material comprises thermally treating the first cement material in combination with one or more additives.

21 . The method of claim 20 , wherein the one or more additives comprise a byproduct of the first reacting step and/or are formed from the one or more byproducts of the first reacting step.

22 . The method of claim 20 , wherein the one or more additives comprise an aluminum and/or iron compound.

23 . The method of claim 20 , wherein thermally treating is performed at a temperature of 1100° C. to 1800° C.

24 . The method of claim 19 , wherein the composite cement material comprises Portland cement clinker.

25 . An apparatus comprising:
(i) a container configured to react a calcium-bearing starting material with a first acid to produce a first aqueous fraction comprising an aqueous first calcium salt and a first solid fraction comprising one or more solid byproducts; (ii) a system configured to separate the first aqueous fraction from the first solid; (iii) a system configured to treat the first calcium salt, optionally with one or more additives, to produce a first cement material; and (iv) a system configured to treat the first cement material, optionally in the presence of one or more additives, to produce a composite cement material, wherein (i)-(iv) are operably connected.

26 . The apparatus of claim 25 , wherein the system for treating the first calcium salt to produce a first cement material is further configured to regenerate the first acid.

27 . A method of producing a cement material and a supplementary cementitious material (SCM) comprising:
reacting a calcium-bearing starting material with a first acid to produce a first aqueous fraction comprising an aqueous first calcium salt and a first solid fraction comprising one or more solid byproducts comprising a silicon compound; separating the first aqueous fraction from the first solid fraction; producing the SCM from the calcium-depleted solid fraction comprising the silicon compound; and treating the first calcium salt to produce a first cement material.

28 . The method of claim 27 , further comprising treating the first cement material to produce a composite cement material.

29 . The method of claim 28 , wherein the composite cement material comprises Portland cement clinker.

30 . The method of claim 27 , wherein the silicon compound comprises silica fume.

Assignees

• California Inst Of Techn
• Brimstone Energy Inc

Inventors

• Finke Cody E
• Leandri Hugo F

Classifications

• C04B7/246

  from waste building materials, e.g. waste asbestos-cement products, demolition waste · CPC title

• C04B11/30

  with hydraulic cements, e.g. Portland cements · CPC title

• C04B28/04

  Portland cements · CPC title

• C04B11/005 Primary

  Preparing or treating the raw materials · CPC title

• C04B2/10 Primary

  Preheating, burning calcining or cooling (decarbonation during burning of cement raw materials C04B7/43; {obtaining CaO or MgO otherwise than by thermal decomposition of the corresponding carbonates C01F11/02, C01F5/02}) · CPC title