Claims:1. A solgel of formula (1):

formula (1)
wherein formula (1) represents sodium complex of tetra-methyl ammonium silicate (200) prepared from tetra-methyl ammonium silicate (200a) and sodium silicate (200b).
2. The solgel as claimed in claim 1, wherein:
- Physical state of the solgel is of liquid appearance,
- Molecular mass of the solgel is 242.39 g/mol,
- Color of the solgel is yellow,
- pH value of the solgel is from 11 to 13,
- Boiling point of the solgel is of 100°C initial (water),
- Vapor pressure of the solgel is < 1 mm Hg at 20°C,
- Relative density of the solgel is 1.072, and
- Viscosity of the solgel is of 50 mPa.sec.

3. A method for synthesis of solgel for optimizing the viscosity of iron ore slurry, the method comprising:
mixing 8 to 12 equivalents of water with 0.5 to 1.5 equivalent of sodium silicate (200b) for forming a mixture;
heating the mixture at a predefined temperature ranging from 120 to 170°C for a first predefined time ranging from 120 to 180 minutes until polymerization of sodium silicate (200b); and
adding 0.5 to 1.5 equivalent of tetra-methyl ammonium silicate (200a) into the mixture and mixing tetra-methyl ammonium silicate (200a) for a second predefined time ranging from 10 to 15 minutes.

4. The method as claimed in claim 4, wherein the tetra-methyl ammonium silicate (200a) is 15-20% by weight in water.
5. The method as claimed in claim 4, wherein the iron ore slurry includes 75% of solid and rest being water.
6. The method as claimed in claim 7, wherein the solid being Goethite rich ore.
7. The method as claimed in claim 7, wherein dosing of the solgel in the range of 2000-5000 ppm in the iron ore slurry. , Description:TECHNICAL FIELD
[0001] The present disclosure described herein, in general, relates to optimizing or reducing the viscosity of iron ore slurry, particularly of goethite rich ore slurry which has a solid concentration of 75% by weight. In particular, the present disclosure relates to a viscosity optimizing solgel and a method to synthesis it.
BACKGROUND
[0002] The background description includes information that may be useful in understanding the present disclosure. It is not an admission that any of the information provided herein is prior art or relevant to the presently claimed subject matter, or that any publication specifically or implicitly referenced is prior art.
[0003] Viscosity or resistance to flow of the iron ore slurry is a key factor that affects the unit operations involving transportation, pumping, and beneficiation of the solids of the iron ore slurry as the transportation of the solids, pumping and the beneficiation of the iron ore that uses wet grinding requires the solids of the iron ore slurry to have a low viscosity and a high flowing characteristics. Furthermore, even the percentage of solids in the iron ore slurry affects the viscosity as iron ore is highly hydrophilic due to the presence of silica and alumina which forms liquid bridges between the molecules and makes the slurry viscous. The adhesion forces dominate and prove as a barrier for the free flow of the iron ore slurry. Fig.1 shows a graph which depicts the effect of increasing the percentage of solid in the iron ore slurry on viscosity under a constant shear rate of 250 radians per second (RPS). It can be seen in the fig. 1 that with the increase in the percentage of solids in the iron ore slurry, the viscosity increases exponentially. It has been found that the viscosity of iron ore slurries having a percentage of solids more than 50% by weight is often problematic in the unit operations. Goethite rich iron ore slurry is one such type of iron ore slurry which faces the problem of high viscosity as it contains 75% solid by weight.
[0004] There are many solutions available to optimize the viscosity of the iron ore slurry. One such obvious solution is to increase the quantity of water in the slurry. However, such a solution cannot be applied always as only a specific quantity of water can be added to make the slurry. Adding an additional amount of water more than the specified quantity will cause a problem in further operations. Therefore, in yet another solution, the addition of a reagent is well-known to optimize the viscosity of the slurry without any modification in the water content in the iron ore slurry. The known reagents used are alpha-olefin sulphonate detergent, acids, anhydrides, amides, and their mixtures, organic polymers, surfactants, and their mixture, microcrystalline cellulose, synthetic flocculants, polyacrylamide or organic polymer dispersant, polyacrylic or polymethacrylic acid or anionic derivative. However, using the above-mentioned reagents consumes a lot of time in synthesis and is often cumbersome to handle. Furthermore, the reagents are costly and don’t provide a considerable decrease in the viscosity of the iron ore slurry which affects unit operations.
[0005] In view of the above, there is a need to provide a reagent that mitigates the shortcomings of the above-mentioned reagents and considerably optimize the viscosity of the iron ore slurry.
OBJECTS OF THE DISCLOSURE
[0006] Some of the objects of the present disclosure, which at least one embodiment herein satisfy, are listed hereinbelow.
[0007] It is a general object of the present disclosure to provide a solgel that can be easily handled and considerably optimize or reduce the viscosity of the iron ore slurry, in particular, goethite rich ore slurry.
[0008] It is another object of the present disclosure to provide a method for synthesizing the solgel for reducing or optimizing the viscosity of the iron ore slurry that takes less time.
[0009] Another object of the present subject matter is to provide a solgel and a method to synthesis the solgel that is economical.
[0010] These and other objects and advantages will become more apparent when reference is made to the following description and accompanying drawings.
SUMMARY
[0011] This summary is provided to introduce concepts related to a solgel and a method for synthesis of the solgel for optimizing the viscosity of iron ore slurry. The concepts are further described below in the detailed description. This summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter.
[0012] The subject matter disclosed herein relates to a solgel which is a Group 1 metal complex of tetra-alkyl or tetra-aryl ammonium silicate prepared from the reaction between group 1 metal salt of silicate and tetra-alkyl or tetra-aryl ammonium silicate. In a preferred embodiment, the solgel is a sodium complex of tetra-methyl ammonium silicate prepared from sodium silicate and tetra-methyl ammonium silicate.
[0013] The subject matter disclosed herein also relates to a method for synthesis of solgel for reducing or optimizing the viscosity of iron ore slurry. The method comprises mixing 8-12 equivalents of water (H2O) with 0.5 to 1.5 equivalent of group 1 metal salt of silicate for forming a mixture. The method proceeds with heating the mixture at a predefined temperature for first predefined time until polymerization of group 1 metal salt of silicate. In an exemplary embodiment, the predefined temperature ranges from 120-170°C and the first predefined time ranges from 120-180 minutes. The final step of the method is adding 0.5 to 1.5 equivalent of tetra-methyl ammonium silicate into the mixture and mixing tetra-alkyl or tetra-aryl ammonium silicate for a second predefined time. In an exemplary embodiment, the second predefined time ranges from 10-15 minutes. In a preferred embodiment, the group 1 metal salt of silicate is sodium silicate and tetra-alkyl or tetra-aryl ammonium silicate is tetra-methyl ammonium silicate.
[0014] The solgel and the method for its synthesis require less time and are easy to handle. Further, the reactants used for the synthesis of solgel are cheap and easily available. The experiments carried out with the disclosed solgel showed a decrease of viscosity of iron ore slurry up to 50 mPa.sec.
[0015] In order to further understand the characteristics and technical contents of the present subject matter, a description relating thereto will be made with reference to the accompanying drawings. However, the drawings are illustrative only but not used to limit the scope of the present subject matter.
[0016] Various objects, features, aspects, and advantages of the inventive subject matter will become more apparent from the following detailed description of preferred embodiments, along with the accompanying drawing figures in which like numerals represent like components.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] It is to be noted, however, that the appended drawings illustrate only typical embodiments of the present subject matter and are therefore not to be considered for limiting of its scope, for the invention may admit to other equally effective embodiments. The detailed description is described with reference to the accompanying figures. The illustrated embodiments of the subject matter will be best understood by reference to the drawings, wherein like parts are designated by like numerals throughout. The following description is intended only by way of example, and simply illustrates certain selected embodiments of devices, systems, and methods that are consistent with the subject matter as claimed herein, wherein:
[0018] Fig. 1 illustrates a graph depicting an effect of an increasing percentage of solid in an iron ore slurry on viscosity under a constant shear rate of 250 radians per second (RPS);
[0019] Fig. 2 illustrates a synthesis reaction for making a solgel in accordance with the present disclosure;
[0020] Fig. 3 illustrates a block diagram of a method for making a solgel in accordance with the present disclosure;
[0021] Fig. 4a illustrates a graph depicting viscosity trend with time at a constant shear rate (250 RPS) for iron ore slurry;
[0022] Fig. 4a illustrates a graph depicting viscosity trend at a variable shear rate (1-1000 RPS) for iron ore slurry;
[0023] Fig. 5a illustrates a graph depicting viscosity trend with time at a constant shear rate (250 RPS) for sodium silicate used as a viscosity reducing agent;
[0024] Fig. 5b illustrates a graph depicting viscosity trend variable shear rate (1-1000 RPS) for sodium silicate used as a viscosity reducing agent;
[0025] Fig. 6a illustrates a graph depicting viscosity trend with time at a constant shear rate (250 RPS) for solgel used as a viscosity reducing agent in accordance with the present disclosure; and
[0026] Fig. 6b illustrates a graph depicting viscosity trend variable shear rate (1-1000 RPS) for solgel used as a viscosity reducing agent in accordance with the present disclosure.
[0027] The figures depict embodiments of the present subject matter for the purposes of illustration only. A person skilled in the art will easily recognize from the following description that alternative embodiments of the structures and methods illustrated herein may be employed without departing from the principles of the disclosure described herein.
DETAILED DESCRIPTION
[0028] The detailed description of various exemplary embodiments of the disclosure is described herein with reference to the accompanying drawings. It should be noted that the embodiments are described herein in such details as to clearly communicate the disclosure. However, the amount of details provided herein is not intended to limit the anticipated variations of embodiments; on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the present disclosure as defined by the appended claims.
[0029] It is also to be understood that various arrangements may be devised that, although not explicitly described or shown herein, embody the principles of the present disclosure. Moreover, all statements herein reciting principles, aspects, and embodiments of the present disclosure, as well as specific examples, are intended to encompass equivalents thereof.
[0030] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments. As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises”, “comprising”, “includes” and/or “including,” when used herein, specify the presence of stated features, integers, steps, operations, elements and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components and/or groups thereof.
[0031] It should also be noted that in some alternative implementations, the functions/acts noted may occur out of the order noted in the figures. For example, two figures shown in succession may, in fact, be executed concurrently or may sometimes be executed in the reverse order, depending upon the functionality/acts involved.
[0032] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which example embodiments belong. It will be further understood that terms, e.g., those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.
[0033] The present disclosure is directed to reducing or optimizing the viscosity of the iron ore slurry, particularly of goethite rich ore slurry which has a solid (goethite rich ore) concentration of 75% by weight and the rest 25% being water (H2O). Accordingly, fig. 2 shows a synthesis reaction for making a solgel for reducing the viscosity of an iron ore slurry. Reactant tetra-methyl ammonium silicate ((CH3)4N(OH).2SiO2) represented by reference numeral 200a that is taken in a predefined quantity reacts with another reactant which is an aqueous solution of sodium silicate (Na2SiO3) represented by reference numeral 200b taken in a predefined quantity and maintained at a predefined temperature range to form a sodium complex of tetra-methyl ammonium silicate represented by reference numeral 200, the so-called solgel in accordance with the present disclosure. Since sodium silicate 200b is formed from sodium (Na) which is an alkali metal belonging to group 1 elements of the periodic table, sodium silicate 200b is extremely soluble in water owing to the larger dimension of the sodium metal ions compared to other ions from the same period, having a lower charge density, and could easily be separated from their anions and easily dissolved in polar solvents such as water. The concentration of sodium oxide (Na2O) and silicon dioxide (SiO2) in sodium silicate 200b is 10.6% and 26.5% by weight respectively. The tetra-methyl ammonium silicate 200a is 15-20% by weight in water. The reactants 200a and 200b used for the synthesis of the solgel are easily available and cheap. Table 1 below provides various physical and chemical properties of the solgel. The amount or dosage of the solgel used in the iron ore slurry ranges from 2000 to 5000 ppm.
Table 1: Various properties of the solgel
Physical State Color Molecular Mass (g/mol) pH Value Boiling point, (°C) Vapor pressure (mmHg at 20°C) Relative Density Viscosity, (mPa.sec)
Liquid Yellow 242.39 11-13 100 Less than 1 1.072 50

[0034] The present disclosure also provides a method 300 for synthesizing the solgel for reducing or optimizing the viscosity of the iron ore slurry, particularly goethite rich ore slurry which comprises 75% (by weight) of goethite rich ore (solids) in the slurry and the rest 25% being water (H2O). The method 300 as shown in fig. 3 comprises mixing of water (H2O) with sodium silicate (Na2SiO3) 200b for forming a mixture represented by block 302. In an exemplary embodiment, 8-12 equivalents of water is mixed with 0.5 to 1.5 equivalent of sodium silicate 200b in a mixing device. The mixing device can be but not limited to a beaker, tumbler, bowl, etc. made of any type of material like metal, alloys, ceramic, etc. The mixture is then heated to a predefined temperature for a first predefined time until polymerization of sodium silicate 200b takes place, the method step being enclosed in block 304. In an exemplary embodiment, the predefined temperature ranges from 120 to 170°C and the first predefined time ranges from 120 to 180 minutes. The final step of the method 300 as represented by block 306 involves the addition of tetra-methyl ammonium silicate ((CH3)4N(OH).2SiO2) 200a into the heated mixture and mixing tetra-methyl ammonium silicate 200a for a second predefined time which results in the formation of the solgel. In an exemplary embodiment, 0.5 to 1.5 equivalent of tetra-methyl ammonium silicate 200a is added to the mixture and the second predefined time of mixing the tetra-methyl ammonium silicate 200a is 10 to 15 minutes. One of the advantages of the present disclosed method 300 is that it requires less time for the synthesis of the solgel. The solgel is able to reduce the viscosity of the iron ore slurry either in a dissolved state or dispersible form. Since the pH value of the solgel ranges from 11 to 13 as given in table 1, the solgel is alkaline or basic in nature. Also, it is easy to handle the solgel as it is in a liquid state.
Experimentation results of viscosity trend of iron ore slurry without viscosity reducing reagents given by a rheometer
[0035] Fig. 4a shows a graph depicting the time-dependent behavior (thixotropic) of the iron ore slurry at a constant shear rate (250 RPS). The iron ore slurry comprises 75% by weight of goethite rich ore solids. The viscosity of the iron ore slurry has been found out to be 350 mPa.sec at the constant shear rate (250 RPS). Such a high viscosity is problematic to unit operations like slurry transportation, grinding, etc. Fig. 4b shows a graph showing a specific decrease in the viscosity of iron ore slurry with the increasing shear rate (1-1000 RPS) showing shear thinning behavior of the iron ore slurry. The viscosity, however, is not reduced or optimized to an appreciable or permissible value. Therefore, reagents are added in the iron ore slurry to reduce or optimize its viscosity.
Experimentation results of viscosity trend of iron ore slurry with viscosity reducing reagents given by a rheometer
Case 1: Use of sodium silicate as the reagent
[0036] Fig. 5a shows a graph depicting the time-dependent behavior (thixotropic) of the iron ore slurry at a constant shear rate (250 RPS) with sodium silicate added to the slurry. It has been found that viscosity has been decreased from 35 to 60 mPa.sec with the use of sodium silicate as the reagent. It is also found from the graph of fig. 5b that there has been a specific decrease in the viscosity of the iron ore slurry with increasing the shear rate (1-1000 RPS) showing shear thinning behavior of the slurry.
Case 2: Use of solgel as the reagent
[0037] Fig. 6a shows a graph depicting the time-dependent behavior (thixotropic) of the iron ore slurry at a constant shear rate (250 RPS) with solgel of the present disclosure added to the slurry. It has been found that the effect of solgel on the viscosity of the iron ore slurry having 75% by weight solid concentration is much more effective as compared to that given by using sodium silicate. The viscosity has been decreased from 350 to 50 mPa.sec with the addition of the solgel at the constant shear rate (250 RPS). It the value of the achieved viscosity is 10 mPa.sec less than that achieved by using sodium silicate. Variable shear rate experimentation as shown in fig. 6b also confirmed the shear-thinning behavior of the iron ore slurry. The behavior of the iron ore slurry has changed from time-dependent to time-independent with the addition of the solgel which suggests that the effect of time on the iron ore slurry is insignificant with the use of solgel. This aspect has some potential applications in the aspect of the processing of iron ore slurry especially in wet grinding and slurry transportation through the pump.
[0038] Table 2 provided below captures the observations or results of the viscosity trend of iron ore slurry with and without viscosity reducing reagents given by the rheometer. The function of a rheometer is already known and therefore for the sake of brevity the same is not disclosed here.
Table 2: Viscosity trend of iron ore slurry with and without viscosity reducing reagents
Sample Viscosity (mPa.s) Rheological behavior Behavior
Iron ore slurry 350 Shear-thinning Time-dependent Thixotropic
Iron ore slurry + sodium silicate 60 Shear-thinning Time independent Pseudoplastic
Iron ore slurry + solgel 50 Shear-thinning Time independent Pseudoplastic

TECHNICAL ADVANTAGES
[0039] The present disclosure provides a solgel that can be easily handled and considerably reduces or optimizes the viscosity of the iron ore slurry, in particular, goethite rich ore slurry.
[0040] The present disclosure provides a method for synthesizing the solgel for reducing or optimizing the viscosity of the iron ore slurry that takes less time.
[0041] The present disclosure provides a solgel and a method to synthesis the solgel that is economical.
Equivalents:
[0042] A description of an embodiment with several components in communication with each other does not imply that all such components are required. On the contrary, a variety of optional components are described to illustrate the wide variety of possible embodiments of the invention. When a single device or article is described herein, it will be apparent that more than one device/article (whether or not they cooperate) may be used in place of a single device/article. Similarly, where more than one device or article is described herein (whether or not they cooperate), it will be apparent that a single device/article may be used in place of the more than one device or article or a different number of devices/articles may be used instead of the shown number of devices or programs. The functionality and/or the features of a device may be alternatively embodied by one or more other devices which are not explicitly described as having such functionality/features. Thus, other embodiments of the invention need not include the device itself.
[0043] The specification has described a solgel for reducing or optimizing the viscosity of the iron ore slurry and a method to synthesis it.
[0044] The illustrated steps in the present disclosure are set out to explain the exemplary embodiments shown, and it should be anticipated that ongoing technological development will change the manner in which particular functions are performed. These examples are presented herein for purposes of illustration, and not limitation. Further, the boundaries of the functional building blocks have been arbitrarily defined herein for the convenience of the description. Alternative boundaries can be defined so long as the specified functions and relationships thereof are appropriately performed. Alternatives (including equivalents, extensions, variations, deviations, etc., of those described herein) will be apparent to persons skilled in the relevant art(s) based on the teachings contained herein. Such alternatives fall within the scope and spirit of the disclosed embodiments. Also, the words "comprising," "having," "containing," and "including," and other similar forms are intended to be equivalent in meaning and be open-ended in that an item or items following any one of these words is not meant to be an exhaustive listing of such item or items, or meant to be limited to only the listed item or items. It must also be noted that as used herein and in the appended claims, the singular forms “a,” “an,” and “the” include plural references unless the context clearly dictates otherwise.
[0045] Finally, the language used in the specification has been principally selected for readability and instructional purposes, and it may not have been selected to delineate or circumscribe the inventive subject matter. It is therefore intended that the scope of the invention be limited not by this detailed description, but rather by any claims that issue on an application based here on. Accordingly, the embodiments of the present invention are intended to be illustrative, but not limiting, of the scope of the invention, which is set forth in the following claims.