CA1138900A - Granular foam-glass material and method for the production thereof - Google Patents
Granular foam-glass material and method for the production thereofInfo
- Publication number
- CA1138900A CA1138900A CA000340912A CA340912A CA1138900A CA 1138900 A CA1138900 A CA 1138900A CA 000340912 A CA000340912 A CA 000340912A CA 340912 A CA340912 A CA 340912A CA 1138900 A CA1138900 A CA 1138900A
- Authority
- CA
- Canada
- Prior art keywords
- glass
- foam
- granular
- foamed
- length
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B19/00—Other methods of shaping glass
- C03B19/10—Forming beads
- C03B19/108—Forming porous, sintered or foamed beads
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
- C03C11/00—Multi-cellular glass ; Porous or hollow glass or glass particles
- C03C11/007—Foam glass, e.g. obtained by incorporating a blowing agent and heating
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B14/00—Use of inorganic materials as fillers, e.g. pigments, for mortars, concrete or artificial stone; Treatment of inorganic materials specially adapted to enhance their filling properties in mortars, concrete or artificial stone
- C04B14/02—Granular materials, e.g. microballoons
- C04B14/04—Silica-rich materials; Silicates
- C04B14/22—Glass ; Devitrified glass
- C04B14/24—Glass ; Devitrified glass porous, e.g. foamed glass
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Organic Chemistry (AREA)
- Materials Engineering (AREA)
- Ceramic Engineering (AREA)
- Civil Engineering (AREA)
- Manufacturing & Machinery (AREA)
- Structural Engineering (AREA)
- Life Sciences & Earth Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Glass Compositions (AREA)
- Processing And Handling Of Plastics And Other Materials For Molding In General (AREA)
Abstract
ABSTRACT
A novel granular foam-glass material consists of fragments of a foam-glass body and has at least 100,000,preferably at least 1,000,000 bubbles per cm3 of at least approximately the same size. The foam-glass material of this invention is obtained by grinding the raw material into a flour, mixing this with an inflating agent which releases gas when heated, inflating the mixture, in a flat-bed furnace, to form a flat length of foam-glass, cooling this glass after it has been inflated, and crushing it into granules after it has been cooled. The foamed glass material of this invention has better compressive strength than can be obtained with known processes wherein the foam-glass has a structure lacking homogeneity.
A novel granular foam-glass material consists of fragments of a foam-glass body and has at least 100,000,preferably at least 1,000,000 bubbles per cm3 of at least approximately the same size. The foam-glass material of this invention is obtained by grinding the raw material into a flour, mixing this with an inflating agent which releases gas when heated, inflating the mixture, in a flat-bed furnace, to form a flat length of foam-glass, cooling this glass after it has been inflated, and crushing it into granules after it has been cooled. The foamed glass material of this invention has better compressive strength than can be obtained with known processes wherein the foam-glass has a structure lacking homogeneity.
Description
31~0~
~ lethods are already known (cf. Swiss Patents 426 601 and 473 741) for producing granular foam-glass material from glass-flour and an inflating agent which releases gas at high temperatures.
These methods required that the raw material be first ground into a flour, that this flour be mixed with an inflating agent which releases gas when heated, and that rough grains be produced from this mixture. The rough granular material thus obtained is then pre-heated in a furnace or on a drying belt, pref-erably with a parting agent, and is inflated.
Granular foam-glass material thus produced has a structure lacing 10 homogeneity, since the size and distribution of the bubbles in the surface areas of individual grains differed from that in the interior thereof. This resulted in a decrease in compressive strength in the surface areas of individual grains, and thus in an overall decrease in compressive strength.
Also known ~cf. Luxemburg Patent 79 661, German OS 2 206 448 and
~ lethods are already known (cf. Swiss Patents 426 601 and 473 741) for producing granular foam-glass material from glass-flour and an inflating agent which releases gas at high temperatures.
These methods required that the raw material be first ground into a flour, that this flour be mixed with an inflating agent which releases gas when heated, and that rough grains be produced from this mixture. The rough granular material thus obtained is then pre-heated in a furnace or on a drying belt, pref-erably with a parting agent, and is inflated.
Granular foam-glass material thus produced has a structure lacing 10 homogeneity, since the size and distribution of the bubbles in the surface areas of individual grains differed from that in the interior thereof. This resulted in a decrease in compressive strength in the surface areas of individual grains, and thus in an overall decrease in compressive strength.
Also known ~cf. Luxemburg Patent 79 661, German OS 2 206 448 and
2 224 009) are methods for producing foam-glass blocks or slabs which may, if necessary, be reduced to granules, but none of these publications contain any lnformation regarding the physical and mechanical properties of the granular material thus obtained. It is, however, obvious to one skilled in the art that these methods will provide only a product having a relatively small 30 number of coarse pores of various sizes, of relatively high specific weight, and low compressive strength.
It is a purpose of the invention to provide a granular foam-glass materiaI having lmproved compressive strength, with the same or lower specific weight as the already known material, and to provide a simple and inexpensive ,.~
, . .
113~3~t00 method for producing such a granular foam-glass material.
This invention relates to foamed granular glass, characterized in that it consists of fragments of a foamed glass element having at least 100,000 cavities per CM3 of at least approximately the same size, and that it has a compressive strength greater than 130 KG/CM2, and has a specific weight of about 0.25.
The grains of the material may have broken or knurled edges.
The invention also relates to a method for producing the granular foam-glass material according to the invention, the said method being charact-erized in that the raw material is ground to a flour, the said flour is mixed with an organic and/or inorganic inflating agent which releases gas when heated,the mixture thus obtained is heated, in a flat-bed furnace, to form a flat length of foam-glass which is quenched after being inflated and, after cooling, is broken down into a granular material.
The inflating agent is preferably applied to the glass in a uniform layer.
The mixture of flour and inflating agent is pre-dried, before inflat-ing, so carefully that the chemically combined water in the inflating agent is not expelled.
Internal stress causes the length of foam-glass break down into gran-ules almost automatically upon abrupt cooling, but this may also be achieved by mechanica] crushing.
The lengths of foam-glass are preferably produced upon a circulating, endless caterpillar-track material-carrier, made of steel strip or separate elements, with the upper run enclosed in a flat-bed furnace.
..Y~
The thickness of the glass to be inflatecl is preferably such that the thermal capacity thereof, per lmit of area, is greater than that of the material-carrier, and the glass is preferably cooled by cooling the said material-carrier.
The outer surface of the material carrier is preferably coated with a layer of al~inum-o~ide or iron-aluminum alloy.
In producing granular foam-glass material, the grains of which have knurled edges, the granular material obtained is processed mechanically in such a manner that the edges are broKen. mis may be accomplished with a device operating after the fa~on of a sugar-coating (? dragée-producing) drum.
m e method according to the invention produces an extremely fine-pored, very light granular material which is highly suitable as an additive for light-weight concrete and as a filler for plastics. More particularly, the granular foam-glass material obtained has up to 3,000,000 closed bubbles per cm , a specific weight of 0.25, and a compressive strength of more than 130 kg/cm . Such physical properties cannot be obtained with a material which is granulated in the raw condition and is then inflated.
20An inflating agent is first made by stirring the following into a thin paste:
100 parts by weight of water 32 parts by weight of water-glass (28 Bé) 4 parts by weight of glycerine (unpurified) 15 parts by weight of sodium bentonite (clear bentonite).
500 parts by weight of finely ground glass flour are added to the inflating agent thus obtained. m e mixture is dried at between 120 and 180 C
~3 `` 113~Q6:) and is passed, if necessary, through a 0.~ mm-mesh screen.
A layer of glass-f].our thus activated, measuring betwe.en 0.5 and 5 cm in thickness, and either in the composition given above or with an addi-tion of up to five times the amour.t of glass-flour, is inflated briefl.y in a.]ink-belt furnace at 780C. At the outlet from the furnace, the emerging length of foam-glass is quenched and reduced to the resuired grain si~e.
If a coarse granular material is requirecl, mechanica.l crushing may be omitted, if the quenching is very abrupt, e.g. if water is used, which causes the foam-glass to break up because of interna]. stresses. m e thinner the length of foam-glass, the finer the granular material obtained.
It is a purpose of the invention to provide a granular foam-glass materiaI having lmproved compressive strength, with the same or lower specific weight as the already known material, and to provide a simple and inexpensive ,.~
, . .
113~3~t00 method for producing such a granular foam-glass material.
This invention relates to foamed granular glass, characterized in that it consists of fragments of a foamed glass element having at least 100,000 cavities per CM3 of at least approximately the same size, and that it has a compressive strength greater than 130 KG/CM2, and has a specific weight of about 0.25.
The grains of the material may have broken or knurled edges.
The invention also relates to a method for producing the granular foam-glass material according to the invention, the said method being charact-erized in that the raw material is ground to a flour, the said flour is mixed with an organic and/or inorganic inflating agent which releases gas when heated,the mixture thus obtained is heated, in a flat-bed furnace, to form a flat length of foam-glass which is quenched after being inflated and, after cooling, is broken down into a granular material.
The inflating agent is preferably applied to the glass in a uniform layer.
The mixture of flour and inflating agent is pre-dried, before inflat-ing, so carefully that the chemically combined water in the inflating agent is not expelled.
Internal stress causes the length of foam-glass break down into gran-ules almost automatically upon abrupt cooling, but this may also be achieved by mechanica] crushing.
The lengths of foam-glass are preferably produced upon a circulating, endless caterpillar-track material-carrier, made of steel strip or separate elements, with the upper run enclosed in a flat-bed furnace.
..Y~
The thickness of the glass to be inflatecl is preferably such that the thermal capacity thereof, per lmit of area, is greater than that of the material-carrier, and the glass is preferably cooled by cooling the said material-carrier.
The outer surface of the material carrier is preferably coated with a layer of al~inum-o~ide or iron-aluminum alloy.
In producing granular foam-glass material, the grains of which have knurled edges, the granular material obtained is processed mechanically in such a manner that the edges are broKen. mis may be accomplished with a device operating after the fa~on of a sugar-coating (? dragée-producing) drum.
m e method according to the invention produces an extremely fine-pored, very light granular material which is highly suitable as an additive for light-weight concrete and as a filler for plastics. More particularly, the granular foam-glass material obtained has up to 3,000,000 closed bubbles per cm , a specific weight of 0.25, and a compressive strength of more than 130 kg/cm . Such physical properties cannot be obtained with a material which is granulated in the raw condition and is then inflated.
20An inflating agent is first made by stirring the following into a thin paste:
100 parts by weight of water 32 parts by weight of water-glass (28 Bé) 4 parts by weight of glycerine (unpurified) 15 parts by weight of sodium bentonite (clear bentonite).
500 parts by weight of finely ground glass flour are added to the inflating agent thus obtained. m e mixture is dried at between 120 and 180 C
~3 `` 113~Q6:) and is passed, if necessary, through a 0.~ mm-mesh screen.
A layer of glass-f].our thus activated, measuring betwe.en 0.5 and 5 cm in thickness, and either in the composition given above or with an addi-tion of up to five times the amour.t of glass-flour, is inflated briefl.y in a.]ink-belt furnace at 780C. At the outlet from the furnace, the emerging length of foam-glass is quenched and reduced to the resuired grain si~e.
If a coarse granular material is requirecl, mechanica.l crushing may be omitted, if the quenching is very abrupt, e.g. if water is used, which causes the foam-glass to break up because of interna]. stresses. m e thinner the length of foam-glass, the finer the granular material obtained.
Claims (15)
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. Foamed granular glass, characterized in that it consists of fragments of a foamed glass element having at least 100,000 cavities per CM3 of at least approximately the same size, and that is has a compressive strength greater than 130 KG/CM2 , and has a specific weight of about 0.25.
2. Foamed granular glass according to claim 1, characterized in that it contains at least 500,000 cavities per cm3.
3. Foamed granular glass according to claim 2, characterized in that it contains at least 1,000,000 cavities per cm3.
4. Foamed granular glass material according to one of claims 1 to 3, characterized in that the grains of the material have broken edges.
5. A method for producing a granular foam-glass material according to claim 1, characterized in that the raw materials are ground into a flour, the said flour is mixed with at least one of an organic or inorganic inflating agent which releases gas when heated, the said mixture is inflated, in a flat-bed furnace, into a flat length of foam-glass which is quenched after inflation, and is reduced to granular material immediately after cooling.
6. A method according to claim 5, characterized in that the inflating agent is applied in a uniform layer to the surface of the glass.
7. A method according to claim 5, characterized in that the mixture of flour and inflating agent is pre-dried, before being inflated, so carefully that the water chemically combined in the inflating agent is not expelled.
8. A method according to one of claims 5 to 7, characterized in that the length of foam-glass is broken down by mechanical crushing.
9. A method according to claim 5, characterized in that the length of foam-glass is produced upon a circulating, endless, caterpillar-track material-carrier, made of steel strip or separate elements, the upper run thereof being enclosed in a flat-bed furnace.
10. A method according to claim 9, characterized in that the thickness of the length of glass to be inflated is such that the thermal capacity thereof, per unit of area, is greater than that of the material-carrier.
11. A method according to claim 9 or 10, characterized in that the length of inflated foam-glass is cooled by cooling the material-carrier.
12. A method according to claim 9, characterized in that the outer surface of the material-carrier is coated with an aluminum-oxide or aluminum-iron alloy.
13. A method according to claim 5, characterized in that the granular material obtained is processed in such a manner as to break the edges thereof.
14. A method according to claims 5, 7 or 9, characterized in that said foamed glass material contains at least 500,000 cavities per cm3.
15. A method according to claims 5, 7 or 9, characterized in that said foamed glass material contains at least 1,000,000 cavities per cm3.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CH12265/78-1 | 1978-11-30 | ||
| CH1226578A CH637606A5 (en) | 1978-11-30 | 1978-11-30 | FOAM GLASS GRANULES AND PROCESS FOR PRODUCTION. |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1138900A true CA1138900A (en) | 1983-01-04 |
Family
ID=4381405
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000340912A Expired CA1138900A (en) | 1978-11-30 | 1979-11-29 | Granular foam-glass material and method for the production thereof |
Country Status (10)
| Country | Link |
|---|---|
| US (1) | US4332908A (en) |
| EP (1) | EP0012114B1 (en) |
| JP (1) | JPS55500940A (en) |
| AT (1) | ATE14204T1 (en) |
| CA (1) | CA1138900A (en) |
| CH (1) | CH637606A5 (en) |
| DE (1) | DE2967482D1 (en) |
| DK (1) | DK324980A (en) |
| ES (1) | ES8100230A1 (en) |
| WO (1) | WO1980001162A1 (en) |
Families Citing this family (22)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5261875A (en) * | 1991-02-14 | 1993-11-16 | Wayne State University | Method and apparatus for injection of gas hydrates |
| US5599296A (en) * | 1991-02-14 | 1997-02-04 | Wayne State University | Apparatus and method of delivery of gas-supersaturated liquids |
| US5086620A (en) * | 1991-02-14 | 1992-02-11 | Wayne State University | Method of microencapsulation of hyperbaric gas |
| ES2004767A6 (en) * | 1987-07-27 | 1989-02-01 | Pietsch Tibor | Artificial pumice stone. |
| GB8726940D0 (en) * | 1987-11-18 | 1987-12-23 | Ward B L | Strengthened glass |
| US5569180A (en) * | 1991-02-14 | 1996-10-29 | Wayne State University | Method for delivering a gas-supersaturated fluid to a gas-depleted site and use thereof |
| EP0661240B1 (en) * | 1993-12-16 | 1997-11-05 | Lias-Franken Leichtbaustoffe GmbH & Co. KG | Foam glass granulate and method for its manufacture |
| US5772714A (en) * | 1995-01-25 | 1998-06-30 | Shin-Etsu Quartz Products Co., Ltd. | Process for producing opaque silica glass |
| CH692579A5 (en) * | 1998-03-23 | 2002-08-15 | Ingeborg Viol | Composite molding. |
| DE19860878C2 (en) * | 1998-12-18 | 2003-10-16 | Hermsdorfer Inst Tech Keramik | Filler for organic and inorganic polymers and uses of a polymer material with such a filler |
| EP1044938A1 (en) * | 1999-04-16 | 2000-10-18 | Misapor AG | Flowable and curable castable masses, in particular lightweight concrete, element or building material, and method for obtaining structured surfaces thereon |
| US7008535B1 (en) | 2000-08-04 | 2006-03-07 | Wayne State University | Apparatus for oxygenating wastewater |
| US6964809B2 (en) * | 2002-02-15 | 2005-11-15 | Pedro M. Buarque de Macedo | Large high density foam glass tile |
| US8453400B2 (en) * | 2003-07-22 | 2013-06-04 | Pedro M. Buarque de Macedo | Prestressed, strong foam glass tiles |
| US7311965B2 (en) * | 2003-07-22 | 2007-12-25 | Pedro M. Buarque de Macedo | Strong, high density foam glass tile having a small pore size |
| DE102004040307A1 (en) * | 2004-08-19 | 2006-02-23 | Walter Frank | Foam glass cooling section |
| AT501684B9 (en) | 2004-10-07 | 2007-06-15 | Technopor Handels Gmbh | LIGHTWEIGHT CONCRETE |
| EP1767503A1 (en) * | 2005-09-22 | 2007-03-28 | Saint-Gobain Revetex S.r.l. | Foamed glass granules for reinforcing structures in general, process for manufacturing said granules and structure reinforced with the same |
| US7695560B1 (en) | 2005-12-01 | 2010-04-13 | Buarque De Macedo Pedro M | Strong, lower density composite concrete building material with foam glass aggregate |
| AT505718B1 (en) | 2007-08-23 | 2010-01-15 | Technopor Handels Gmbh | PROCESS FOR THE PRODUCTION OF LIGHT CONCRETE |
| DE102009003303B3 (en) * | 2009-01-04 | 2010-02-04 | Schaumglas Global Consulting Gmbh | Method for the production of foam glass, comprises supplying a raw mixture from a mixing container over a supply arrangement with uniform scrubber supply on a glass nonwoven strip and/or glass nonwoven segment |
| CN104909576A (en) * | 2015-06-12 | 2015-09-16 | 大连生命之石新材料有限公司 | Sponge body foamed glass formula and production process thereof |
Family Cites Families (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DK96707C (en) * | 1960-01-30 | 1963-08-19 | Villadsens Fab As Jens | Process for making foam glass and oven intended for carrying out the process. |
| BE637983A (en) | 1961-05-02 | |||
| SE314938B (en) * | 1961-05-18 | 1969-09-15 | Kreidl W | |
| DE1301009B (en) * | 1965-08-05 | 1969-08-14 | Wasagchemie Ag | Device and process for the continuous production of foam glass or ceramic |
| US3562370A (en) * | 1966-09-29 | 1971-02-09 | Owens Corning Fiberglass Corp | Method of producing cellular bodies having high compressive strength |
| US3666506A (en) * | 1969-04-01 | 1972-05-30 | Corning Glass Works | Batch for producing cellulated glassy bodies from rock |
| DE2206448A1 (en) | 1972-02-11 | 1973-08-16 | Helmut Dipl Ing Pieper | METHOD OF MANUFACTURING FOAM GLASS |
| JPS535213A (en) * | 1976-07-05 | 1978-01-18 | Chichibu Cement Kk | Manufacture of inorganic foamed bodies |
| US4143202A (en) * | 1976-09-23 | 1979-03-06 | Maryland Environmental Service | Ash coated cellular glass pellet |
| GB1597154A (en) * | 1977-05-19 | 1981-09-03 | Bfg Glassgroup | Glass beads |
-
1978
- 1978-11-30 CH CH1226578A patent/CH637606A5/en not_active IP Right Cessation
-
1979
- 1979-11-26 ES ES486344A patent/ES8100230A1/en not_active Expired
- 1979-11-27 WO PCT/CH1979/000150 patent/WO1980001162A1/en unknown
- 1979-11-27 DE DE7979810166T patent/DE2967482D1/en not_active Expired
- 1979-11-27 AT AT79810166T patent/ATE14204T1/en not_active IP Right Cessation
- 1979-11-27 EP EP79810166A patent/EP0012114B1/en not_active Expired
- 1979-11-27 US US06/200,506 patent/US4332908A/en not_active Expired - Lifetime
- 1979-11-27 JP JP50198479A patent/JPS55500940A/ja active Pending
- 1979-11-29 CA CA000340912A patent/CA1138900A/en not_active Expired
-
1980
- 1980-07-28 DK DK324980A patent/DK324980A/en not_active Application Discontinuation
Also Published As
| Publication number | Publication date |
|---|---|
| JPS55500940A (en) | 1980-11-13 |
| EP0012114B1 (en) | 1985-07-10 |
| ES486344A0 (en) | 1980-11-01 |
| CH637606A5 (en) | 1983-08-15 |
| WO1980001162A1 (en) | 1980-06-12 |
| DK324980A (en) | 1980-07-28 |
| US4332908A (en) | 1982-06-01 |
| DE2967482D1 (en) | 1985-08-14 |
| ATE14204T1 (en) | 1985-07-15 |
| ES8100230A1 (en) | 1980-11-01 |
| EP0012114A1 (en) | 1980-06-11 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry |