Low-cost, high early strength, acid-resistant pozzolanic cement

• US 5,352,288 A
• Filed: 06/07/1993
• Issued: 10/04/1994
• Est. Priority Date: 06/07/1993
• Status: Expired due to Fees

• Current Assignee: Dynastone Lc
• Original Assignee: Dynastone Lc
• Inventors: Mallow, William A.
• Primary Examiner(s): Bell, Mark L.
• Assistant Examiner(s): MARCANTONI, PAUL D
• Application Number:
  US08/073,346
• Time in Patent Office: 484 Days
• Field of Search: 106/624, 106/667, 106/704, 106/707, 106/708, 106/714, 106/721, 106/791, 106/792, 106/692, 106/716, 106/724, 106/737, 106/709, 106/672, 106/676, 106/677, 106/605, 106/606 , 106/611, 106/612, 106/DIG. 2
• US Class Current: 106/605
• CPC Class Codes: C04B 11/00 Calcium sulfate cements
• CPC Class Codes: C04B 12/04 Alkali metal or ammonium silicate cements ; Alkyl silicate cements; Silica sol cements; Soluble silicate cements alkali metal silicates per se, their preparation C01B33/32; ammonium silicates per se, their preparation C01C1/00
• CPC Class Codes: C04B 18/162 Cement kiln dust; Lime kiln dust
• CPC Class Codes: C04B 20/002 Hollow or porous granular materials
• CPC Class Codes: C04B 20/0048 Fibrous materials
• CPC Class Codes: C04B 2111/23 Acid resistance, e.g. against acid air or rain
• CPC Class Codes: C04B 22/062 of the alkali or alkaline-earth metals
• CPC Class Codes: C04B 28/18 containing mixtures of the silica-lime type
• CPC Class Codes: C04B 40/04 Preventing evaporation of the mixing water permanent coverings C04B41/00
• CPC Class Codes: C04B 7/00 Hydraulic cements calcium sulfate cements C04B11/00
• CPC Class Codes: Y02W 30/91 Use of waste materials as fillers for mortars or concrete
• CPC Class Codes: Y10S 106/02 Perlite

Abstract

A low cost cement composition that can be admixed with water and hydrothermally closed cured to give acid-resistant products of high compressive strength consisting essentially of, in parts by weight, 1 to 1.5 parts of a calcium oxide material containing at least about 60% CaO, 10 to 15 parts of pozzolanic material containing at least about 30% by weight amorphous silica, and 0.025 to 0.075 parts by weight of an alkali metal catalyst and building materials made therefrom as well as the method of making such building materials by closed curing.

Claims

1. A low cost cement composition that can be admixed with water and closed cured to give acid-resistant products of high compressive strength consisting essentially of, in parts by weight, 1 to 1.5 parts of a calcium oxide material containing at least about 60% CaO, 10 to 20 parts of pozzolanic material containing at least about 30% by weight amorphous silica, and 0.025 to 0.075 parts by weight of an alkali metal catalyst.

2. The composition of claim 1 wherein said calcium oxide material is a kiln dust, quick lime, slake lime or mixture thereof.

3. The composition of claim 2 wherein said pozzolanic material is, in addition to said amorphous silica, a fly ash, blast furnace slag, fume silica, bagasse ash, rice hull ash, volcanic ash, diatomaceous earth, calcined fuller'"'"'s earth, diatomaceous silica, or mixtures thereof.

4. The composition of claim 3 wherein the alkali metal catalyst is sodium hydroxide, postassium hydroxide, sodium silicate, potassium silicate, or a mixture thereof.

5. The composition of claim 1, including an expanded filler selected from hollow glass cenospheres, perlite, expanded polystyrene beads, glass or polymer microspheres, vermiculite, or mixtures thereof.

6. The composition of claim 1 including ceramic, graphite, or plant fibers.

7. The composition of claim 1 including a portland cement, high alumina cement, or plaster of paris.

8. A low cost, high compressive strength cementitious building material consisting of a closed cured composition consisting essentially of a low cost, high strength, hydrothermal cement composition that can be admixed with water and closed cured to give products of high compressive strength consisting essentially of, in parts by weight, 1 to 1.5 parts of a calcium oxide material containing at least about 60% CaO, 10 to 20 parts of pozzolanic material containing at least about 30% by weight amorphous silica, and 0.025 to 0.075 parts by weight of an alkali metal catalyst.

9. The material of claim 8 wherein said calcium oxide material is a kiln dust, quick lime, slake lime or mixture thereof.

10. The material of claim 9 wherein said pozzolanic material is, in addition to said amorphous silica, a fly ash, blast furnace slag, fume silica, bagasse ash, rich hull ash, volcanic ash, diatomaceous earth, calcined fuller'"'"'s earth, diatomaceous silica, or mixtures thereof.

11. The material of claim 10 wherein the alkali metal catalyst is sodium hydroxide, potassium hydroxide, sodium silicate, potassium silicate, or mixtures thereof.

12. The material of claim 10 including an expanded filler selected from hollow glass cenospheres, perlite, expanded polystyrene beads, glass or polymer microspheres, vermiculite, or mixtures thereof.

13. The material of claim 10 including ceramic, graphite, or plant fibers.

14. The material of claim 10 including a portland cement, high alumina cement, or plaster of paris.

15. The method of making a low-cost, high compressive strength cement comprising forming a pulverulent hydrothermal cement composition consisting essentially of, in parts by weight, 1 to 1.5 parts of a calcium oxide material containing at least about 60% CaO, 10 to 20 parts of pozzolanic material containing at least about 30% by weight amorphous silica, and 0.025 to 0.075 parts by weight of an alkali metal catalyst, adding sufficient water thereto to permit closed curing of said composition, forming said admixture to the shape of building material desired, and closed curing said shape at ambient temperature or above.

16. The method of claim 15 wherein said calcium oxide material is a kiln dust, quick lime, slake lime or mixture thereof.

17. The method of claim 16 wherein said pozzolanic material is, in addition to said amorphous silica, a fly ash, blast furnace slag, fume silica, bagasse ash, rice hull ash, volcanic ash, diatomaceous earth, calcined fuller'"'"'s earth, diatomaceous silica, or mixtures thereof.

18. The method of claim 17 wherein the alkali metal catalyst is sodium hydroxide, potassium hydroxide, sodium silicate, potassium silicate, or mixtures thereof.

19. The method of claim 18 including including an expanded filler selected from hollow glass cenospheres, perlite, expanded polystyrene beads, glass or polymer microspheres, vermiculite, or mixtures thereof.

20. The method of claim 19 including ceramic, graphite, or plant fibers.

21. The method of claim 20 including a portland cement, high alumina cement, or plaster of paris.