Claims:We claim:
1. A process of preparation of lightweight geo-polymer tile, comprising the steps of:
(a) preparing an alkaline solution by adding sodium silicate solution to sodium hydroxide solution;
(b) preparing mixture of ground granulated blast furnace slag and fly ash;
(c) adding the alkaline solution of step (a) and a super plasticizer such as polycarboxylic ether to the mixture of ground granulated blast furnace slag and fly ash, and mixing to obtain a paste;
(d) adding thermocol beads to the above paste, and blending to obtain blended paste;
(e) molding the obtained paste in a mould;
(f) covering the mould with a polyethylene cover to avoid air entrapment and leaving for 24 hours at ambient temperature, to obtain a moulded tile; and
(g) de-moulding the obtained tile, and water curing for 7 days at room temperature to obtain the hardened lightweight geo-polymer tile.
2. The process of preparation as claimed in claim 1, wherein the proportion of ground granulated blast furnace slag and fly ash to be used in preparing mixture as in step (b) is selected by testing density and strength of each mixture proportion.
3. The process of preparation as claimed in claim 1, wherein the mixture of ground granulated blast furnace slag and fly ash is in proportion selected from 60:40, 70:30, and 50:50.
4. The process of preparation as claimed in claim 1, wherein the quantity of alkaline solution is 50 % of the total weight of ground granulated blast furnace slag and fly ash.
5. The process of preparation as claimed in claim 1, wherein the quantity of super plasticizer is 0.8-0.85 % of the total weight of ground granulated blast furnace slag and fly ash.
6. The process of preparation as claimed in claim 1, wherein the quantity of thermocol is 1.5% of the total weight of ground granulated blast furnace slag and fly ash.

Dated this 21st day of September 2019

V.GIRIJA (IN/PA-1478) Agent for Applicant

, Description:FIELD OF THE INVENTION
[001] The present invention relates to construction materials, particularly to the process of preparation of lightweight geo-polymer tiles using industrial waste products.
BACKGROUND OF THE INVENTION
[002] Presently, the demand of construction materials is extremely high due to progress and expansion of global infrastructural facility. On one end continued usage of natural sources for the production of building materials is causing an ecological imbalance and on the other end, industrial wastes are posing a great problem to the environment. Significant research works have been carried out to balance these parameters with a socio-economic concern. In this regard, geo-polymer technology would provide a substantial solution to overcome these issues.
[003] The production of conventional tiles requires more energy and natural sources. The production cost of the tiles is also considerably expensive. Some research works on production of industrial waste based geo-polymer tiles have shown that they are durable and less expensive when compared with other conventional tiles. There are several varieties of geo-polymer tiles and their processes are revealed under prior art search.
[004] The known processes for producing ceramic tiles by using pure materials like feldspar, kaolinite, quartz, talc, etc. as raw materials is disclosed in Dana, K, Das, S and Das, S. K, 2004, J. Eur. Ceram.Soc. 24: 3169-3175. A process for self-glazed Geopolymer tiles using fly ash and GGBFS is disclosed in US 20070221100. The process of developing Geopolymer product is mentioned in WO 2013044325Al, which explicates the production of roof tiles of conventional density as well as lightweight and ultra-lightweight roof tiles.
[005] The process of present invention is more efficient and economic compared to the known processes and it is detailed below in the description section.
OBJECTS OF THE INVENTION
[006] The main object of the invention is to provide a lightweight geo-polymer tile using industrial waste materials.
[007] It is another object of the invention to provide a process of preparation of lightweight geo-polymer tile, which reduces the adverse environmental impact, cost of production and conserve the natural sources and energy.
[008] Other objects of the invention will be apparent from the description of the invention herein below.
SUMMARY OF THE INVENTION
[009] The present invention discloses a process of preparation of lightweight geo-polymer tile, comprising the steps of:
(a) preparing an alkaline solution by adding sodium silicate solution to sodium hydroxide solution;
(b) preparing mixture of ground granulated blast furnace slag and fly ash;
(c) adding the alkaline solution of step (a) and a super plasticizer such as polycarboxylic ether to the mixture of ground granulated blast furnace slag and fly ash, and mixing to obtain a paste;
(d) adding thermocol beads to the above paste, and blending to obtain blended paste;
(e) molding the obtained paste in a mould;
(f) covering the mould with a polyethylene cover to avoid air entrapment and leaving for 24 hours at ambient temperature, to obtain a moulded tile; and
(g) de-moulding the obtained tile, and water curing for 7 days at room temperature to obtain the hardened lightweight geo-polymer tile.
[0010] The tiles produced by said process has bubble surface or textured finish to initiate anti-skid properties.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] The following drawings form the part of the present invention and are included to substantiate and demonstrate the invention purely by way of example and non-limiting in which:
Fig. 1 illustrates a non-limiting exemplary embodiment of determining dimensions of the hardened cylindrical specimen made of geo-polymer paste
Fig. 2 illustrates a non-limiting exemplary embodiment of testing hardened cylindrical specimen made of geo-polymer paste by using Universal testing machine (UTM) to determine the maximum load
Fig. 3 illustrates comparative strength of different geo-polymer mix compositions
Fig. 4 illustrates a non-limiting embodiment of flexure testing of geo-polymer tile
Fig. 5 illustrates a non-limiting embodiment of determining Moh’s Scale of hardness of tile.
DETAILED DESCRIPTION OF THE INVENTION
[0012] As those of ordinary skill in the art will understand, various features of the embodiments illustrated and described with reference to any one of the Figures may be combined with features illustrated in one or more other Figures to produce alternative embodiments that are not explicitly illustrated and described. The combinations of features illustrated provide representative embodiments for typical applications. However, various combinations and modifications of the features consistent with the teachings of the present disclosure may be desired for particular applications or implementations. Those of ordinary skill in the art may recognize similar applications or implementations consistent with the present disclosure, e.g., ones in which components or processes are arranged in a slightly different order than shown in the embodiments in the Figures. Those of ordinary skill in the art will recognize that the teachings of the present disclosure may be applied to other applications or implementations.
[0013] The aspects and embodiments of the invention are described, referring to the accompanying drawings or figures.
[0014] In an aspect of the exemplary embodiment, the invention provides geo-polymer tile(s), particularly a lightweight geo-polymer tile.
[0015] In an exemplary embodiment, the geo-polymer tile comprises geo-polymer mixture, the mixture comprises ground granulated blast furnace slag (GGBS) and fly ash as binders.
[0016] In an exemplary embodiment, the physical and chemical properties of GGBS and fly ash; and chemical composition of sodium hydroxide and sodium silicate are tested and determined prior to usage of these in the preparation of geo-polymer tile.
[0017] In a non-limiting embodiment, the physical and chemical properties of GGBS are shown in the below table 1:
Table 1: Physical and Chemical properties of GGBS
S.No DESCRIPTION VALUES
Physical properties
1 Specific gravity 2.91
2 Fineness ( Blain’s air permeability – m2/kg ) 382
Chemical properties
3 MnO ( % by mass) 0.11
4 Sulphur (S) ( % by mass) 0.44
5 Sulphate (SO3) ( % by mass ) 0.21
6 MgO ( % by mass) 7.55
7 Insoluble Residue(I.R) ( % by mass ) 0.32
8 Chloride Content (Cl) ( % by mass ) 0.006
9 Glass Content ( % by mass) 92
10 LOI ( % by mass) 0.1
11 Moisture content ( % by mass) 0.01
12 CaO+MgO+1/3 Al2O3
SiO2+2/3 Al2O3 1.11
13 CaO+MgO+Al2O3
SiO2 1.96
[0018] In a non-limiting embodiment, the physical and chemical properties of Fly ash are shown in the below table 2:
Table 2: Physical and Chemical properties of Fly ash
S. No DESCRIPTION VALUES
Physical properties
1 Specific gravity 1.94
2 Fineness ( Blain’s air permeability – m2/kg ) 186
3 Soundness by autoclave test (percent) 0.039
4 Residue on 45 micron sieve (percent) 39.7
Chemical properties
5 SiO2 ( % by mass) 65.07
6 SiO2 + Al2O3 + Fe2O3 ( % by mass) 93.47
7 MgO ( % by mass) 0.77
8 Total sulphur as sulphur trioxide SO3 ( % by mass) 0.1
9 Alkalis Na2O 0.88
10 Total chloride 0.004
11 LOI ( % by mass) 0.45
[0019] In an exemplary embodiment of the invention, the geo-polymer tile is prepared using alkaline solution comprising sodium hydroxide and sodium silicate.
[0020] In a non-limiting exemplary embodiment the chemical composition of sodium hydroxide is shown in below table 3.
Table 3: Chemical composition of sodium hydroxide
Appearance Flakes
Sodium Hydroxide ( % by mass ) 97
Sodium Carbonate ( % by mass ) 2
Chlorides (Cl) ( % by mass ) 0.01
Sulphates (SO4) ( % by mass ) 0.01
Phosphate (PO4) ( % by mass ) 0.001
Iron (Fe) ( % by mass ) 0.005
Heavy metals ( % by mass ) 0.001
[0021] In a non-limiting exemplary embodiment the chemical composition of sodium silicate is shown in below table 4.
Table 4: Chemical composition of sodium silicate
Appearance Clear less viscous liquid
Specific Gravity 1.35
SiO2 ( % by mass ) 62
Mg2O ( % by mass ) 12.1
Chlorides (Cl) ( % by mass ) 0.05
Sulphates (SO4) ( % by mass ) 0.05
Iron (Fe) ( % by mass ) 0.005
Heavy metal (as Pb) 0.001
Loss on ignition (at 7000C) ( % by mass ) 36
Water content ( % by mass ) 25.794
[0022] In an exemplary embodiment, the geo-polymer composition mixture is prepared with different ratios (weight) of GGBS and fly ash; and determining the density and strength of each composition.
[0023] In an exemplary embodiment, the geo-polymer composition mixture prepared using different ratios of GGBS and fly ash, is poured in to a cylindrical mould and then covered with polyethylene wrappers or cover to avoid air entrapment.
[0024] The dimension of the cylindrical mould can vary depend on the dimension of the tile to be prepared, in a non-limiting example, the cylindrical mould or the cylindrical specimen is of height 30mm and diameter 30mm.
[0025] In an exemplary embodiment, the cylindrical specimen is prepared as a new approach to check the optimized strength of the mixture by varying proportions of GGBS and fly ash.
[0026] In an exemplary embodiment, the prepared cylindrical specimen is left for drying at ambient temperature condition for 24 hours, after the drying process is completed the cylindrical specimen is demoulded and the dimensions are measured as shown in Fig. 1 to determine the strength of binders per unit area.
[0027] In an exemplary embodiment, the density of the cylindrical specimen prepared from different proportions of GGBS and fly ash is determined and are shown in table 5.
Table 5: Density of cylindrical sepcimen prepared from different composition
S. No Mix proportion (GGBS:FA) Density in kg/m3
1 M1 - 80:20 2009.4
2 M2 - 70:30 2004.7
3 M3 - 60:40 1990.5
4 M4 - 50:50 1966.9
5 M5 - 40:60 1919.8
6 M6 - 30:70 1858.5
7 M7 - 20:80 1778.3
[0028] In an exemplary embodiment, the demoulded cylindrical specimen is water cured for 28 days and then the obtained cured mould is tested by Universal Testing Machine (UTM) to determine the maximum load that the cylindrical specimen can withstand, and the testing is done as shown in Fig. 2, and the results are shown in the table 6.
Table 6: Average compressive strength of mix composition
S. No Mix proportion (GGBS:FA) Compressive strength (N/mm2)
1 M1 - 80:20 70.73
2 M2 - 70:30 67.35
3 M3 - 60:40 77.93
4 M4 - 50:50 68.55
5 M5 - 40:60 62.50
6 M6 - 30:70 58.81
7 M7 - 20:80 53.23
[0029] The compressive strengths of the tiles prepared using different composition of geo-polymer mixture after 28 days of curing is shown in Fig. 3.
[0030] In an aspect the invention provides a process of preparation of lightweight geo-polymer tile includes steps of preparing alkaline solution and casting of tile.
[0031] In a non-limiting exemplary embodiment, the step of preparation of alkaline solution includes steps of: weighing sodium hydroxide flakes and mixing with water in a ratio of 1:4 and dissolving the flakes by stirring; placing the solution in a closed container for 30-45 mins and leaving it undisturbed until the solution gets cooled to room temperature; adding sodium silicate solution to the sodium hydroxide solution in the ratio of 1:1 and mixing; closing the solution container lid and leaving the solution undisturbed for 24 hrs. The alkaline solution is prepared 24 hours prior to its use in the process of preparation of geo-polymer tile.
[0032] In an exemplary embodiment, the casting of tile includes the steps of:
(a) preparing mixture of ground granulated blast furnace slag (GGBS) and fly ash (FA);
(b) adding the prepared alkaline solution and a super plasticizer such as polycarboxylic ether to the mixture of ground granulated blast furnace slag and fly ash, and mixing to obtain a paste;
(c) adding thermocol beads to the above paste, and blending to obtain blended paste;
(d) molding the obtained paste in a mould;
(e) covering the mould with a polyethylene cover to avoid air entrapment and leaving for 24 hours at ambient temperature, to obtain a moulded tile; and
(f) de-moulding the obtained tile, and water curing for 7 days at room temperature to obtain the hardened lightweight geo-polymer tile.
[0033] In a non-limiting exemplary embodiment, the mixture of ground granulated blast furnace slag (GGBS) and fly ash (FA) is prepared by weighing the required proportions of GGBS and FA. The lumps in GGBS and FA are broken and the dry mix is mixed well.
[0034] In an exemplary embodiment, the super plasticizer such as polycarboxylic ether (PCE) is added to achieve required workability for moulding without adding excess water.
[0035] In a non-limiting exemplary embodiment, the quantity of super plasticizer is in the range of 0.8-0.85 % of the total weight of binders i.e GGBS and Fly ash.
[0036] In an exemplary embodiment, the alkaline solution and the super plasticizer are added to the mixture of GGBS and Fly ash and mixed well to obtain a paste. In order to obtain consistent paste, mixing by hand or machine may be used.
[0037] In a non-limiting exemplary embodiment, the quantity of alkaline solution is 50 % of total weight of binders i.e GGBS and Fly ash.
[0038] In a non-limiting exemplary embodiment, the quantity of thermocol bead is 1.5% of the total weight of binders i.e ground granulated blast furnace slag and fly ash.
[0039] In a non-limiting exemplary embodiment, the mould is of dimension 30 ? 30 ? 1 cm.
[0040] In an embodiment, the geo-polymer tile prepared by the process of the present disclosure is tested for flexure test, Moh’s hardness test, and water absorption.
[0041] In a non-limiting exemplary embodiment, the flexure test of the geo-polymer tile is performed under point loading and failure loading as shown in Fig. 4. The density of different mix tiles and the results are shown below in table 7.1 and 7.2 respectively.
Table 7.1: Density of tile for different composition
Mix composition (GGBS:FA) Density
(kg/m3)
M1 – 70:30 922.22
M2 – 60:40 920.00
M3 – 50:50 916.11
Table 7.2: Breaking strength and modulus of rupture of the tile for different composition
Mix composition (GGBS:FA) Breaking strength (N)
IS 13630(part 6) : 2006 Modulus of rupture
(N/mm2)
IS 13630(part 6) : 2006
M1 – 70:30 887.988 13.31
M2 – 60:40 659.568 9.89
M3 – 50:50 590.110 8.85
[0042] In a non-limiting exemplary embodiment, the Moh’s scale of hardness of the geo-polymer tile is determined as per IS 13630 (Part 13): 2006 as shown in fig. 5, and the results are tabulated in below table 8.
Table 8: Moh’s hardness (scale) of tile for different composition
Mix composition (GGBS:FA) Scratch hardness of surface (Moh’s scale) IS 13630
(Part 13) : 2006
M1 - 70:30 4 - 4.5
M2 - 60:40 4.5 – 5
M3 - 50:50 4 – 4.5
[0043] In a non-limiting exemplary embodiment, the water absorption of the geo-polymer tile is conducted as per IS 13630-part 2: 2006 for different mixture of tile composition and the results are tabulated in the below table 9.
Table 9: Water absorption of different compositions of tile
Mix composition (GGBS:FA) Water absorption (%)
M1 - 70:30 0.60
M2 - 60:40 0.47
M3 - 50:50 0.82
[0044] The geo-polymer tile prepared according to the present disclosure has bubble surface or textured finish to initiate the antiskid properties and for production of this tile the processes such as process for glazing mentioned in the art is not preferred.
[0045] The non-limiting advantages of the process of preparation of geo-polymer tile according to the present disclosure is that the air and water curing both are performed in about ambient temperature and eliminating heat curing process, thereby reducing energy consumption which are generally required for preparing geo-polymer tile.
[0046] Another non-limiting advantage of the process of preparation of geo-polymer tile according to the present disclosure is that as the process employs industrial waste products and ambient curing conditions the production cost of the tile is reduced to 30-40% compared with general lightweight tiles manufactured by known process. In a non-limiting embodiment, the base production cost is in the range of INR 8 to 10 per square foot.
[0047] In a non-limiting embodiment, the tiles prepared according to the present disclosure can be used for wall cladding, false ceiling, rough flooring for warehouse and industries.
[0048] In a non-limiting embodiment, the tiles or panels can be used for interior works instead of general gypsum boards which gets affected periodically due to humidity. This tile of the present disclosure does not show any adverse effect like change of dimensions, bulging or warping.
[0049] While the invention has been described in connection with a preferred embodiment, it is not intended to limit the scope of the invention to the particular form set forth, but on the contrary, it is intended to cover such alternatives, modifications, and equivalents as may be included within the spirit and scope of the invention as defined by the appended claims.