AN ANALYTICAL RESEARCH ON FLY ASH POLYMER MATERIAL WITH INNOVATIVE IDEAS
Shalini Singh
Research Scholar, Rajiv Gandhi Proudyogiki Vishwavidalaya Bhopal (M.P.) Prof. Rajesh Joshi
Asso. Prof. Department of Civil Engineering, Rajiv Gandhi Proudyogiki Vishwavidalaya Bhopal (M.P.)
Abstract - Modern waste like fly-debris which is making natural issues, is essentially utilized as a structure material because of its minimal expense and simple accessibility. In any case, the principle impediment of these blocks is its low strength. In this way, a great deal of examination is proceeding to build the strength of these blocks. The current examination work is completed to foster another methodical methodology to deliver fly debris composite blocks which will have higher compressive strength. Here the fly-debris is blended in with Cold setting gum at various extents and water treated at various temperatures to discover an answer for the block business. The compressive strength, Hardness, water retention, Density and warm conductivity of the fly debris tar powder blocks got under ideal test conditions are 11.24 MPa, 47.37HV, 19.09% 1.68 g/cm3, and 0.055 W/mK separately. The sliding wear conduct is likewise researched. The design property connection of these composites are concentrated on utilizing X-beam diffraction, FTIR examination and filtering electron microscopy.
1 INTRODUCTION 1.1 Fly Ash Bricks
The whole advancement of a nation relies upon the creation worth of force and thusly its utilization as energy. Our country, India needs enormous power assets to meet the assumption for its tenant just as its intend to be a created country by 2020. Non-renewable energy source has a significant impact in fulfilling the need for influence age .Coal is viewed as one of the world's most extravagant and generally disseminated petroleum product. All throughout the planet, India overwhelms the third situation in the biggest creation of coal and has the fourth biggest coal holds approx. (197 Billion Tons). It has been assessed that 75% of India's absolute introduced power is warm of which the portion of coal is around 90%. Almost around 600 Million tons of coal is created worldwide consistently, with Fly debris age is around 500 MT at (60-78 %) of entire debris delivered [1, 2].In India, the current age of FA is almost around 180 MT/year and is plausible to increment around 320 MT/year by 2017 and 1000MT/year by 2032 [3]. No uncertainty Indian coal has high debris content and low hotness esteem. To satisfy the expanding testing needs, many coal based nuclear energy stations have been developed. Because of which tremendous measure of combusted buildup as Fly
debris (80 %), and Bottom debris (20%) has been delivered. The finely scattered molecule from the copied coal is released out through the pipe gases which are withdrawn precisely through electrostatic precipitators and separators which are then gathered together in the field of containers. The pace of creation of FA is high and it continues expanding a seemingly endless amount of many years.
The yearly creation of FA in China, India and US is approximated around 275 million metric tons. In any case, not exactly 50% of this is burned-through in different regions. The best test before the handling and assembling ventures is the removal of the remaining side-effects. The destructive effect on the environmental factors proposes the need for fitting unloading of fly debris and legitimizes full use of FA when doable. Side-effects that are for the most part harmful, ignitable, destructive or responsive have inconvenient climate results. This significant issue requires a successful, monetary and eco-accommodating strategy to handle with the removal of the leftover modern side-effects. The issue with safe removal of debris without influencing the climate, upsetting biological equilibrium and the enormous stockpiling region required are significant issues and difficulties for protected and
economical improvement of the country.
Consequently needful endeavors are being made persistently by making severe guidelines by the public authority to completely use the debris. Right now just half of the fly debris is by and large productively used in India [4]. The most widely recognized and practical ways of using these modern squanders items is to go for development of streets, interstates and dikes. The Problem with natural contamination can be extraordinarily diminished if these squanders items be adequately used in development of streets, roadways and dikes. Yet, adequate measure of soil of wanted quality isn't accessible without any problem. So these modern squanders not just utilized as an other for normal soils in the development rather it additionally tackle the issues of removal and climate contamination. This will give various huge advantages to the developing business just as to the nation overall by protection of normal assets, by decrease of volume of waste to landfills, by bringing down the expense of development materials, and by bringing down garbage removal costs.
With the assistance of some appropriate stabilizer like lime, thermosetting saps or concrete, the properties of fly debris can be expanded and it tends to be additionally utilized as a development material. FA shows self - solidifying conduct that is the reason it is utilized in development extensively
1.2 Cold Setting Resin: - An Overview Cold embedding resin is used as a binder to create bonds between particles between FA particles and enhance their strengthening effect. They have excellent resistance to atmospheric and chemical degradation. Resin powder alone cannot be effective until it is mixed with a hardener (or accelerator) to provide an investment material and then polymerized to form the desired block. This process can generate heat, which can be minimized by using cooling air or water.
These compounds are ideal for materials that are sensitive to heat and pressure.
This cold-curing resin provides excellent properties for fly ash moldings. Increased mechanical strength and hardness, resistance to atmospheric and chemical decomposition, reduced thermal conductivity, porosity and void removal,
and rapid curing of pellets are some of the common properties. The curable compound and hardener were sourced from Geosinpvt. Calcutta.
1.3 Objective of the Present Work The purpose of this study is to produce fly ash-polymer composites with different polymer contents and to investigate physical mechanical, thermal conductivity, and wear behavior. In this project, an attempt was made to increase the density and hardness of water-cured cylindrical samples. SEM, XRD, and FTIR analyzes were also performed to investigate fine structure changes.
2 LITERATURE REVIEW 2.1 Introduction
The total installed capacity of India is about 100,000 MW. Of this, 73% of the electricity generated comes from thermal power plants. India's coal reserves are approximately 180 billion tonnes.
Therefore, it is worth noting that 88% of India's thermal power plants utilize this abundant natural resource. There are several power plants in our country, of which about 85 are coal-based. Large amounts of ash (35-50%) and low calorific value (2,800-4,200 kcal / kg) are the physical importance of Indian coal. High- speed coal-fired power is required to produce the required energy, which produces large amounts of ash. In India, the current production of coal ash is about 180 million tons. It should be twice in the next 10 years. In India, wet processes are commonly used to dispose of ash. Producing 1 MW of electricity requires about 1 acre of land and a better initial investment. In our country, the ash pond occupies about 26,300 hectares.
Until 1994, only 3% of the total ash was used. Since then, it has been recognized that the environment in India must be protected, and for this purpose our government proposed the Fly Ash Mission (FAM) in 1994. The main purpose of this mission was the safe disposal and consumption of fly ash. In India, 21 different locations will be selected and 55 FAM technologies will be demonstrated in 10 key areas. Fly ash use increased from 3% to 13% between 1994 and 2002. The Government of India has taken some steps to suggest that MOEF (Government of India Working Agency) use and
consume fly ash better. According to this proposal, all thermal power plants need to reach 20% fly ash consumption in 3 years and 100% in 15 years, and new power plants usually have some exemption, 30 in 3 years. You need to reach%
consumption. % In 9 years. Fly ash is mainly used for compressed embankments and ridges.
3 EXPERIMENTAL WORK AND METHODOLOGY
3.1 Introduction
Fly ash has been used extensively in a variety of architectural and industrial applications. Therefore, consuming this large amount of fly ash greatly reduces the problems that coal-based TPPs encounter in landfills. An analysis of FA performance under various conditions is fundamentally necessary before use.
Therefore, in-situ experiments are not possible to understand the characteristics of FA. There is no other way but to take an exam in the laboratory to assess its
importance. Studies conducted in the laboratory provide a computational approach to control some of the parameters that actually occur.
This section briefly describes the types of materials used, sample preparation and characterization by SEM, XRD, FTIR, mechanical and surface properties such as compressive strength, hardness and wear resistance, thermal conductivity measurement and more.
3.2 Materials Used 3.2.1 Fly ash
The fly ash used in this project was collected dry from an electrostatic precipitator at a private power plant (CPPII). The fine powder was oven dried at 110 °C to 160 °C and stored in a closed bottle for later use.
3.2.2 Cold setting Resin and Binder The resin powder and hardener used in the present study was supplied by Geosyn private Ltd. Kolkata.
4 RESULTS AND DISCUSSION 4.1 Composition of Fly Ash
FA mainly consists Silica (Sio2), Alumina (Al2o3), Calcium Oxide (CaO), and Iron Oxide (Fe2O3). The chemical composition of Fly ash is tabulated in table 4.1.
Compounds SiO2 Al2O3 CaO Mgo P2O5 Fe2o3 SO3 K2O LOI Composition (%) 54.5 26.5 2.1 0.57 0.6 - - - 14.18
Table 4.1 Compositional analysis of Fly ash 4.2 Water Absorption Test
Table 4.2 shows the amount of water absorbed for different FA compositions. The water absorption of FA composites ranges from 15.55% to 19.09%. It can be seen that the overall composition meets the absorption criteria set by some developing countries. In India, soaking a compact for 24 hours gives up to 20% water absorption.
Mix Composition
(Wt. %) Weight (gm) Water Absorption (%) Average Water Absorption Value (%)
Dry Wet
(FA)75%+ (RP)25% 4.579 5.302 15.78 15.55
4.630 5.340 15.33
(FA)80%+ (RP)20% 4.452 5.151 15.70 16.61
4.642 5.456 17.53
(FA)85%+ (RP)15% 4.502 5.356 18.96 19.09
4.329 5.162 19.23
Table 4.2 Percentage (%) water absorbed by various FA polymer compacts Figure 4.1 shows the relationship between
the amount of absorbed water and the density of the dried composite material in FA composition. This figure shows that water intake increases with increasing FA content. 85wt. Absorbs water up to 19.09%. This indicates that most of the pellet openings are open outwards
Figure.4.1 Water absorption and density as a function of FA
Composition 4.3 Density Measurement
The sample density was calculated before and after processing. From Figure 4.2, it can be said that as the weight percentage of FA increases, the density of dry pellets decreases. When the dry compact is immersed in water at 1100 °C to 1800 °C, the capillarity fills the voids and makes it harder, eliminating porosity. As a result, the part becomes denser and eventually becomes denser as the FA content increases.
Fig.4.2 Variation in dry and wet density w.r.t FA composition Mix Composition (Wt. %) Density (g/cm3)
Dry Wet
FA)75%+ (RP)25% 1.40 1.60
(FA)80%+ (RP)20% 1.38 1.62
(FA)85%+ (RP)15% 1.35 1.67
Table 4.3 Density value of dry and wet FA polymer compacts
4.4 Hardness Measurement
Hardness values of all the Fly ash polymer composite of different compositions, both in dry and wet state, were measured by the help of LECO, LM 248AT Vickers hardness tester. The Hardness values as obtained are shown in Table 4.4. The values of hardness are in the range of 32.93 HV – 44.08 HV for dry
composites and 39.78 HV – 47.37 HV for wet FA composites respectively.
S.
No.
Mix Composition (Wt. %)
Density (g/cm3) Dry Wet 1 (FA)75%+ (RP)25% 32.93 39.78 2 (FA)80%+ (RP)20% 38.26 43.04 3 (FA)85%+ (RP)15% 44.08 47.37 Table 4.4 Hardness values of various
FA resin mix compacts
Figure 4.3 shows a comparison of hardness values for dry and wet fly ash composites. From the figure, you can see that you continue to gain weight. FA%, that is NS. As the resin content decreases, the hardness values of both wet and dry compacts increase. Maximum hardness at 85% by weight Reached.
Can be seen from the XRD analysis as shown in Figure 4. 4.4 (b) Water treated at 85 wt%. Compact that generates calcium silicate hydrate (CSH) and calcium aluminate silicate hydrate (CASH) phases that are involved in improving hardness. Both phases are formed by the reaction of Ca (OH) 2, Sio2, and H2O when treated in 1100 C1800 C water.
Fig. 4.3 Variation in hardness values with wt. % of FA
4.5 XRD Analysis
Fig.4.4 (a) XRD analysis of Fly ash and Fig.4.4 (b) XRD analysis of water cured
compact
Figure 4.4 (a) shows that fly ash particles are mainly composed of silicon dioxide and aluminum oxide. Figure 4.4 (b) shows the XRD analysis of water-treated pellets.
It has been found that in the presence of water, a pozzolanic reaction occurs, which results in the formation of a new phase, namely calcium silicate hydrate (CSH) and calcium aluminate silicate hydrate (CASH). These phases are involved in the solidification of unbaked pellets, forming excellent interparticle bonds with improved mechanical properties such as strong structure and hardness. CSH and CASH are considered to be the first reaction products to turn into a semi- crystalline solid phase. A conversion called To Bermorite (C5S6H5).
4.6 Ftir Analysis
Figure 4.5 shows a plot of 100 Fourier Transform Infrared Spectrometer (FTIR) spectrometers and a mixture of 80 + 20%
RP. It can be seen that for the 80 ° mixture, the (%) permeability is reduced compared to 100. Comparing the FTIR spectra reveals the phase transition between FA and the FA mix. The most characteristic difference between these two FTIR spectra is the band shift due to the asymmetric oscillations of SiOSi and AlOSi. The width of the band appeared to be about 1250 cm1 in the FTIR spectrum, which was sharper compared to the FA mix. Then these bands begin to shift to lower frequencies at about (950 cm1).
This shows the formation of a gel-like phase called aluminosilicate associated with the suspension of fly ash in a strongly alkaline activating solution. The expansion and contraction vibration of
SiOAl occurred at about 600 cm1. The wideband groups found in both IR spectra in the 3500 cm1 range are assigned to the stretch (OH) and bend (HOH) oscillations of the bonded water atom and are superficially consumed or captured by the giant indentation of the polymer structure. [30, 31]. This width indicates the presence of strong hydrogen bonds [32].
In summary, water content is a decisive synthetic parameter that affects their mechanical strength. The peak appeared at about 2400 cm-1, which is due to OH expansion and contraction.
The gradual decrease in strength and width of the band indicates that water is being lost. Peaks from 3000 cm-1 to 2000 cm-1 can be due to CH stretching vibrations of organic impurities that may be introduced during sample processing or some hydrocarbons contained in fly ash [33].
Fig.4.5 IR spectra of the FA and FA resin Powder mix
4.7 Determination of Compressive Strength
Compressive strength measurements of cylindrical samples were performed according to common practice. The test was performed on 3 samples of each composition and all averages were evaluated. Table 4.5 shows the intensity values for the various compositions of both dry and wet FAs. For dry composites, compressive strength values range from 6.5 to 11.28 MPa. The 85 wt%
composition had the highest intensity value and the lowest intensity value of 6.5 MPa was increased by 75 wt%.
Zusammensetzung.
S.
No Mix Composition
(Wt. %) Compressive Strength (MPa)
Dry Wet 1 (FA)75%+ (RP)25% 6.5 5.52 2 (FA)80%+ (RP)20% 8.73 7.98 3 (FA)85%+ (RP)15% 11.28 9.43 Table 4.5 Compressive strength values
of different FA resin mix compacts
Fig.4.6 Compressive Strength of Compacts at different FA compositions From Figure 4.6, it can be seen that the composition of (FA) 85% + (RP) 15% has higher compressive strength than the other two compositions. It has been found that the compressive strength increases as the resin content of the fly ash mixture decreases. As you can see from the SEM record, 75wt. Increasing the FA content improves the bond between the interfaces and improves the strength of the part.
These observations confirm that adding excess cold-curing resin powder to fly ash may not be beneficial. Here, the resin powder is used only as a binder. Water treatment has a slight adverse effect on the strength of the composite.
4.8 Thermal Conductivity Measurement
Thermal conductivity is a property of a material that represents its ability to exchange heat. The thermal conductivity of the fly ash-resin-powder mixture was determined by the hot wire method using the KD2 proanalyzer with FA content.
75% by weight of the FA composition showed a maximum thermal conductivity of 0.0552 on average. W/mK. Only FA powder shows higher conductivity values than the other three compositions.
Fig.4.7 Thermal conductivity of FA – Resin powder Mix at different
compositions
4.9 Wear Resistance and Friction Study 4.9.1 Wear Study
The wear properties of FA polymer composites were performed at various loads of 10N and 20N. Figure 4.8 (a) shows a diagram between the wear depth (μm) and time (s) of a dry composite under a load of 10 N. Low compared to the other two composites. It can also be correlated from the results of the hardness values in Table 4.4. 75wt for dry pellets has a lower hardness value than the other two. In both cases, a similar tendency was seen in wear behavior.
Figure 4.8 (b) shows the figure between the wear depth (μm) at a load of 10 N and the time (s) of the wet part. Again, 75wt.
Compact is less tolerant than the other two. Because the hardness value is lower than the other two compositions. The only difference is that in the presence of moisture the wet compact becomes stiffer and the wear depth is reduced to a value of (275 250 µm), which is lower than the dry compact (350-280 µm).
Figures 4.8 (c) and (d) show the evolution between the wear depth (μm) and the time (s) of the dry and wet moldings at a load of 20 N each. 350450 µm. This is a relatively higher value than the dry compact worn by 10N.
Figure 4.8 Wear behavior of FA compacts at different loads Wet compacts are much harder than dry compacts, so a smooth curve appears when a load of 20 N is applied, as shown in Figure (D). In this case, the wear depth value decreases slightly and this curve follows the steady state trend. You can also see that at a load of 20 N at about 300 seconds, the wear depth is the same
regardless of the FA composition. It first reaches a value of 400 µm and then follows a constant horizontal saturation line. In addition, wear behavior can be correlated with the help of wet density.
Figure 4.9 (a and b) shows the change in material loss (gm) over time (s).
It has been found that the loss of material with increasing flextime means that the wear rate decreases over time. Weight loss is higher for dry samples than for water treated samples. There is not much fluctuation due to the load.
Fig.4.9 (a & b) shows the variation in weight loss (gm) with respect to time
(sec).
4.9.2 Friction Study
The frictional behavior of the fly ash- polymer composite is shown in Figure 4.10. The average coefficient of friction (μ) for all composites was given as (1.11.4).
Chapman et al suggested that the thorns in the frictional behavior of the composite may be associated with the formation of defects from the edges of the material.
They estimated that the value of spikes was accompanied by an increase in pitch noise. [29]
From our study, as shown in Figure 4.10 (a & b), the coefficient of friction (μ) increases slightly at first, but after a few seconds, the μ value follows a linear trend during the next test period.
You can also see that the coefficient of
friction decreases as the FA composition increases.
Fig.4.10 (a, b) Variation in co-efficient of friction w.r.t FA composition 4.10 Microstructural Study Of Fly Ash Polymer Composite
4.10.1 SEM Analysis
75, 80, 85wt. The microstructure of the composite material. The plus resin powder mixture was inspected by SEM at various magnifications. The particle size of the FA powder was also determined.
The FA particle size has been shown to be in the 9.6347.6 µm range.
Figure.4.11 (a, b) Particle size distribution of FA powder at different
Magnification
From the SEM images, it was observed that the FA particles were almost spherical, messy, and irregularly shaped.
FA particles form a solidified junk. 75 wt as shown in Figure 4.12 (a). In the composition of, cracks appear in the particle boundary, the pore type of the boundary surface. As the addition of polymer decreases, i. NS. It can be seen that increasing the amount of fly ash improves the interfacial bond and reduces the cracks that occur at the interface.
Further reductions in the amount of resin added provide good compression, but elongated cracks / cavities are seen along the boundaries.
Fig.4.12 Morphology of Fly ash compacts with different composition
and at different magnifications Figure 4.13 shows FESEM images of wear tracks along the sliding direction at various magnifications. These images show that the mechanism of wear is essentially delamination, surface tillage, microcracks, and friction of the friction layer. Figure 4.13 (a) shows that microcracks occur in the direction perpendicular to the slip path, causing surface wear. Figure 4.13 (c) shows the wear trajectory of a dry compact (80
°composition) at a very low magnification.
Fig. 4.13 FESEM image of wear track at different magnification
5.1 CONCLUSIONS
Based on this study, the following conclusions can be drawn.
1) Water treated pellets have a positive effect on hardness values. Of all dry compacts, 85% by weight FA has a higher hardness value of 44.08HV.
Treatment of the composite in water at 1100-1800 ° C significantly improved the hardness value, which increased to 47.37 HV. This increase in hardness value is due to the presence of CSH and CASH in the presence of moisture obtained from XRD analysis.
2) As the amount of polymer (resin powder) added increases, the compressive strength of the dried pellets decreases to a low value of 6.5 MPa. The composition of 75wt shows a lower value. Wet compact does not show a significant decrease in compressive strength.
3) Abrasion tests on various composites can be easily correlated with hardness values. FA is 85wt in both dry and wet conditions.
Composition shows better wear resistance than the other two compositions. Abrasion resistance increases with increasing FA content. The coefficient of friction decreases with increasing FA percentage and follows a linear trend throughout the test period.
4) The thermal conductivity of FA increases with increasing temperature, but in the case of resin
powder/FA mixture, the thermal conductivity of the composite decreases with increasing temperature. It has a much lower conductivity value and can be used in place of clay.
5) Water absorption increases with increasing FA content. At 85% by weight, up to 19% of water is absorbed.
6) The density of dry pellets decreases with increasing FA content. For wet pellets, it increases with increasing FA content.
7) SEM analysis revealed the morphology of FA particles, which are mostly spherical. With reduced polymer addition, i. NS. As the FA content increases, the interface bond becomes better and less cracks are found at the interface.
8) XRD analysis showed that FA particles are mainly composed of silicon dioxide and aluminum oxide, and the proportion of Fe2O3, Cao, etc. is small.
The composite fly ash resin powder produced in this study seems to be suitable as a building material. Making these types of composites will certainly help turn fly ash into a value-added product. On the other hand, reducing the amount of clay used in the production of traditional clay bricks helps protect the environment.
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