Expanded lightweight aggregate made from glass or pumice

• US 9,475,732 B2
• Filed: 04/24/2014
• Issued: 10/25/2016
• Est. Priority Date: 04/24/2013
• Status: Expired due to Fees

• Current Assignee: The Intellectual Gorilla GmbH
• Original Assignee: The Intellectual Gorilla GmbH
• Inventors: Daniels, Evan R., Andersen, Per Just
• Primary Examiner(s): Green, Anthony J
• Application Number:
  US14/785,987
• Publication Number:
  US 20160096774A1
• Time in Patent Office: 915 Days
• US Class Current: 1/1
• CPC Class Codes: C04B 14/045 Alkali-metal containing silicates, e.g. petalite waterglass C04B12/04
• CPC Class Codes: C04B 14/106 Kaolin
• CPC Class Codes: C04B 14/16 porous, e.g. pumice
• CPC Class Codes: C04B 14/22 Glass ; Devitrified glass
• CPC Class Codes: C04B 14/24 porous, e.g. foamed glass
• CPC Class Codes: C04B 18/021 agglomerated by a mineral binder, e.g. cement
• CPC Class Codes: C04B 18/023 Fired or melted materials
• CPC Class Codes: C04B 18/027 Lightweight materials
• CPC Class Codes: C04B 20/0024 expanded in situ, i.e. the material is expanded or made hollow after primary shaping of the mortar, concrete or artificial stone mixture C04B16/085 takes precedence
• CPC Class Codes: C04B 20/04 Heat treatment
• CPC Class Codes: C04B 2111/40 Porous or lightweight materials
• CPC Class Codes: C04B 22/085 containing nitrogen in the anion, e.g. nitrites
• CPC Class Codes: C04B 2201/20 for the density
• CPC Class Codes: C04B 2201/30 for heat transfer properties such as thermal insulation values, e.g. R-values
• CPC Class Codes: C04B 28/26 Silicates of the alkali metals
• CPC Class Codes: C04B 38/009 Porous or hollow ceramic granular materials, e.g. microballoons C04B18/027, C04B20/002 take precedence
• CPC Class Codes: C04B 38/02 by adding chemical blowing agents
• CPC Class Codes: C04B 40/0268 Heating up to sintering temperatures C04B41/0072 takes precedence

Abstract

An expanded lightweight aggregate has compositional ranges (Wt. % Range) of about: (a) 40 to 60% ground glass or pumice, 40 to 60% water, 3 to 15% sodium silicate, and 0.1 to 5% NaNO₃ for the slurry; and (b) 50 to 85% ground glass or pumice, and 15 to 50% slurry for the granulator.

Claims

1. An expanded lightweight aggregate formed from a mixture comprising:

a first ground glass or pumice in the range of about 40 to 60% by weight percent for a slurry;

a water in the range of about 40 to 60% by weight percent for the slurry;

a sodium silicate in the range of about 3 to 15% by weight percent for the slurry;

a NaNO₃ in the range of about 0.1 to 5% for the slurry;

a second ground glass or pumice in the range of about 50 to 85% by weight percent for a granulator;

the slurry in the range of about 15 to 50% by weight percent for the granulator; and

the expanded lightweight aggregate having a particle size comprising about 0-1 mm, 1-2 mm, 2-4 mm, 4-8 mm or a combination thereof.

2. The expanded lightweight aggregate as recited in claim 1, wherein the water is in the range of about 45 to 50% by weight percent for the slurry.

3. The expanded lightweight aggregate as recited in claim 1, wherein the sodium silicate is in the range of about 6 to 7% by weight percent.

4. The expanded lightweight aggregate as recited in claim 1, wherein the NaNO₃ is in the range of about 0.9 to 1.1% by weight percent.

5. The expanded lightweight aggregate as recited in claim 1, the granulator having a ratio of about 1 part of the slurry to about 2.5 parts of the second ground glass or pumice.

6. The expanded lightweight aggregate as recited in claim 1, the expanded lightweight aggregate having a bulk density in the range of about 0.10 to 0.5 g/cm³, a effective density in the range of about 0.10 to 0.8 g/cm³, a compressive strength in the range of about 0.5 MPa to 5 MPa, and a heat conductance in the range of about 0.04 to 0.15 W/mK.

7. An expanded lightweight aggregate formed from a mixture consisting essentially of:

a first ground glass or pumice in the range of about 40 to 60% by weight percent for a slurry;

a water in the range of about 40 to 60% by weight percent for the slurry;

a sodium silicate in the range of about 3 to 15% by weight percent for the slurry;

a NaNO₃ in the range of about 0.1 to 5% for the slurry;

a second ground glass or pumice in the range of about 50 to 85% by weight percent for a granulator; and

the slurry in the range of about 15 to 50% by weight percent for the granulator.

8. The expanded lightweight aggregate as recited in claim 7, wherein the water is in the range of about 45 to 50% by weight percent for the slurry.

9. The expanded lightweight aggregate as recited in claim 7, wherein the sodium silicate is in the range of about 6 to 7% by weight percent.

10. The expanded lightweight aggregate as recited in claim 7, wherein the NaNO₃ is in the range of about 0.9 to 1.1% by weight percent.

11. The expanded lightweight aggregate as recited in claim 7, the granulator having a ratio of about 1 part of the slurry to about 2.5 parts of the second ground glass or pumice.

12. The expanded lightweight aggregate as recited in claim 7, the expanded lightweight aggregate having a diameter of 0-8 mm, a bulk density in the range of about 0.10 to 0.5 g/cm³, a effective density in the range of about 0.10 to 0.8 g/cm³, a compressive strength in the range of about 0.5 MPa to 5 MPa, and a heat conductance in the range of about 0.04 to 0.15 W/mK.

13. The expanded lightweight aggregate as recited in claim 7, the expanded lightweight aggregate having a particle size comprising about 0-1 mm, 1-2 mm, 2-4 mm, 4-8 mm or a combination thereof.

14. A method for manufacturing an expanded lightweight aggregate comprising the steps of:

mixing a first ground glass or pumice in the range of about 40 to 60% by weight percent with water in the range of about 40 to 60% by weight percent to produce a slurry;

adding a sodium silicate in the range of about 3 to 15% by weight percent to the slurry;

adding a NaNO₃ in the range of about 0.1 to 5% to the slurry;

forming aggregates in a granulator by feeding a second ground glass or pumice in the range of about 50 to 85% by weight percent with the slurry in the range of about 15 to 50% by weight percent;

drying the formed aggregates;

heating the dried aggregates together with a finely ground kaolin to a temperature of about 800 to 1400 degrees Celsius; and

cooling the heated aggregates.

15. The method as recited in claim 14, wherein the water is in the range of about 45 to 50% by weight percent to produce the slurry.

16. The method as recited in claim 14, wherein the sodium silicate is in the range of about 6 to 7% by weight percent.

17. The method as recited in claim 14, wherein the NaNO₃ is in the range of about 0.9 to 1.1% by weight percent.

18. The method as recited in claim 14, wherein the finely ground kaolin is about 30% by weight percent.

19. The method as recited in claim 14, the granulator having a ratio of 1 part of the slurry to about 2.5 parts of the second ground glass or pumice.

20. The method as recited in claim 14, further comprising the step of grinding a glass or pumice in a ball mill to produce the ground glass or pumice.

21. The method as recited in claim 14, the ground glass or pumice having a diameter of predominately less than about 100 microns.

22. The method as recited in claim 14, further comprising the step of dividing the cooled aggregates into one or more different end user size ranges.

23. The method as recited in claim 14, further comprising the step of feeding the formed aggregates having a smaller size directly in to a flash drier that heats the formed aggregates above about 800 degrees Celsius to create aggregates in a size of about 0-1 mm.

24. The method as recited in claim 14, the expanded lightweight aggregate having a diameter of 0-8 mm, a bulk density in the range of about 0.10 to 0.5 g/cm³, a effective density in the range of about 0.10 to 0.8 g/cm³, a compressive strength in the range of about 0.5 MPa to 5 MPa, and a heat conductance in the range of about 0.04 to 0.15 W/mK.

25. The method as recited in claim 14, the expanded lightweight aggregate having a particle size comprising about 0-1 mm, 1-2 mm, 2-4 mm, 4-8 mm or a combination thereof.