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

Patent metadata

Field	Value
Publication number	US-2024383804-A1
Application number	US-202418665162-A
Country	US
Kind code	A1
Filing date	May 15, 2024
Priority date	Aug 13, 2019
Publication date	Nov 21, 2024
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

1 .- 30 . (canceled)

31 . 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, wherein treating the first calcium salt to produce a first cement material comprises:
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, or
reacting the aqueous first calcium salt with a base, or
exchanging the one or more anions of the first calcium salt for one or more hydroxyl anions to form a third calcium salt.

32 . The method of claim 31 , 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.

33 . The method of claim 31 , 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.

34 . The method of claim 31 , wherein the first cement material is substantially free of CaCO 3 .

35 . The method of claim 31 , wherein the calcium-bearing starting material is other than CaCO 3 or comprises a material other than CaCO 3 .

36 . The method of claim 31 , wherein the first acid comprises hydrochloric acid.

37 . The method of claim 36 , further comprising regenerating the hydrochloric acid.

38 . The method of claim 31 , wherein the first reacting step is performed at a temperature of at least 50° C.

39 . The method of claim 31 , wherein the first calcium salt is calcium chloride.

40 . The method of claim 31 , wherein the silicon compound comprises SiO 2 .

41 . The method of claim 31 , wherein treating the first calcium salt to produce a first cement material comprises 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.

42 . The method of claim 41 , wherein the second acid comprises sulfuric acid.

43 . The method of claim 31 , wherein the treating step comprises reacting the aqueous first calcium salt with a base to form a third calcium salt.

44 . The method of claim 31 , wherein the treating step comprises exchanging the one or more anions of the first calcium salt for one or more hydroxyl anions to form a third calcium salt.

45 . The method of claim 31 , further comprising treating the first cement material to form a composite cement material.

46 . The method of claim 45 , wherein forming the composite cement material comprises thermally treating the first cement material in combination with one or more additives.

47 . The method of claim 46 , 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.

48 . The method of claim 46 , wherein the one or more additives comprise an aluminum and/or iron compound.

49 . The method of claim 46 , wherein thermally treating is performed at a temperature of 1100° C. to 1800° C.

50 . The method of claim 45 , wherein the composite cement material comprises Portland cement clinker.

Assignees

• California Inst Of Techn
• Brimstone Energy Inc

Inventors

• Finke Cody E
• Leandri Hugo F

Classifications

• C04B28/04

  Portland cements · CPC title

• C01G49/14

  Sulfates {(C01G49/0018 takes precedence)} · CPC title

• C07C1/328

  the hetero-atom being an alkali metal atom · CPC title

• C04B11/30

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

• C01F7/56

  Chlorides (containing fluorine C01F7/52) · CPC title