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234 Int. J. Environment and Waste Management, Vol. 16, No. 3, 2015 Copyright © 2015 Inderscience Enterprises Ltd. Optimising the mixing proportion of solidified landfill waste for sustainable reuse in paving block construction M.A. Hoque Department of Civil and Environmental Engineering, Shahjalal University of Science and Technology, Sylhet-3114, Bangladesh Email address: [email protected] M. Aminul Haque* Department of Civil Engineering, Leading University, Sylhet-3100, Bangladesh Email: [email protected] Email: [email protected] *Corresponding author Abstract: The study optimises the mixing proportion for solidified landfill waste confirming the immobilisation of heavy metal in the waste matrix. Paving blocks were constructed for compressive strength and leachate behaviour analysis. The study revealed the mixing proportion of 1:2 for paving block construction was found to be optimum providing a satisfactory compressive strength of 2,748 psi after 28 days curing period. In addition, cumulative leaching concentrations of Fe, Cu and Ni from the same proportioned solidified blocks were found to be 1.203 mg/l, 0.157 mg/l and 0.493 mg/l respectively along with the nominal rate of release of heavy metals after 28 days of curing period by ensuring the encapsulation of heavy metals in the solidified matrix. The outcome of the study will be potential solution to treat and recycle the harmful wastes as construction materials like paving blocks, river bank protection materials, road construction materials, etc., using S/S techniques. Keywords: immobilisation; landfill waste; leachate; model; optimum; solidification. Reference to this paper should be made as follows: Hoque, M.A. and Haque, M.A. (2015) ‘Optimising the mixing proportion of solidified landfill waste for sustainable reuse in paving block construction’, Int. J. Environment and Waste Management, Vol. 16, No. 3, pp.234–247. Biographical notes: M.A. Hoque is a Professor at the Department of Civil and Environmental Engineering of Shahjalal University of Science and Technology (SUST), Sylhet, Bangladesh. He received his Master of Science in Civil Engineering (Environmental) from Bangladesh University of Engineering and Technology (BUET) in 2003 and graduated with a PhD from University of Southern Queensland (USQ), Australia in 2011. He has more than 16 years of research experience in water and environmental engineering. He has published
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Page 1: IJEWM160305 HAQUE

234 Int. J. Environment and Waste Management, Vol. 16, No. 3, 2015

Copyright © 2015 Inderscience Enterprises Ltd.

Optimising the mixing proportion of solidified landfill waste for sustainable reuse in paving block construction

M.A. Hoque Department of Civil and Environmental Engineering, Shahjalal University of Science and Technology, Sylhet-3114, Bangladesh Email address: [email protected]

M. Aminul Haque* Department of Civil Engineering, Leading University, Sylhet-3100, Bangladesh Email: [email protected] Email: [email protected] *Corresponding author

Abstract: The study optimises the mixing proportion for solidified landfill waste confirming the immobilisation of heavy metal in the waste matrix. Paving blocks were constructed for compressive strength and leachate behaviour analysis. The study revealed the mixing proportion of 1:2 for paving block construction was found to be optimum providing a satisfactory compressive strength of 2,748 psi after 28 days curing period. In addition, cumulative leaching concentrations of Fe, Cu and Ni from the same proportioned solidified blocks were found to be 1.203 mg/l, 0.157 mg/l and 0.493 mg/l respectively along with the nominal rate of release of heavy metals after 28 days of curing period by ensuring the encapsulation of heavy metals in the solidified matrix. The outcome of the study will be potential solution to treat and recycle the harmful wastes as construction materials like paving blocks, river bank protection materials, road construction materials, etc., using S/S techniques.

Keywords: immobilisation; landfill waste; leachate; model; optimum; solidification.

Reference to this paper should be made as follows: Hoque, M.A. and Haque, M.A. (2015) ‘Optimising the mixing proportion of solidified landfill waste for sustainable reuse in paving block construction’, Int. J. Environment and Waste Management, Vol. 16, No. 3, pp.234–247.

Biographical notes: M.A. Hoque is a Professor at the Department of Civil and Environmental Engineering of Shahjalal University of Science and Technology (SUST), Sylhet, Bangladesh. He received his Master of Science in Civil Engineering (Environmental) from Bangladesh University of Engineering and Technology (BUET) in 2003 and graduated with a PhD from University of Southern Queensland (USQ), Australia in 2011. He has more than 16 years of research experience in water and environmental engineering. He has published

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over 40 technical papers in international journals and conferences. He has the experience in supervising postgraduate and undergraduate students. He has also been associated with the Centre for Research, Testing and Consultancy (CRTC) of the Department of Civil and Environmental Engineering, SUST, Bangladesh.

M. Aminul Haque is working as an Assistant Professor in the Department of Civil Engineering, Leading University, Sylhet-3100, Bangladesh. He received his BSc in Civil and Environmental Engineering (2008) and MSc Engineering in Disaster and Environmental Engineering (2013) from Shahjalal University of Science and Technology (SUST), Sylhet-3114, Bangladesh. He has more than six years of research experience in recycling of various wastes in building constructional purposes and green concrete.

1 Introduction

Waste containing heavy metals, are of great concern because of their increasing abundance in the hydrological cycle with relatively high toxicity. Heavy metals have potential impact on human health and the quality of environment having the greater possibility of surface and ground water pollution (Alpaslan and Yukselen, 2002). Conventional method of solid waste landfills without liner system or improper lining with inefficient leachate management system results soil and water pollution by heavy metals and other toxic substances (Bhalla et al., 2012; Longe and Balogun, 2010). In decomposed solid waste of Matuail landfill site, a study conducted by Hoque et al. (2014) noted that the concentration of Fe, Cu and Ni in decomposed solid waste collected from Matuail landfill site during the dry (summer) season were 14,564 mg/kg, 441.5 mg/kg and 895.0 mg/kg respectively while on the contrary the same heavy metal contents were found to be reduced during the wet (monsoon) season. Similarly, high concentrations of heavy metals in landfill site’s solid wastes were also reported by Mamtaz and Chowdhury (2006), Adjia et al. (2008) and Oluyemi et al. (2008) in their respective study. Hoque et al. (2014) also characterised the leachate sample collected from the outlet zone of Matuail landfill site where the concentration of Fe, Cu and Ni were found to be as high as 13.8 mg/l, 0.61 mg/l, 1.78 mg/l respectively that failed to satisfy the Bangladesh standards for inland surface water quality (BECR, 1997). In addition, they observed a significant increase of heavy metals concentration in leachate samples at the monsoon season pointing the possibility of the metals to be released from solid waste to leachate through percolation. During the rainy season, heavy metal leaching rate increases with the high intensity of rainfall because there is a great possibility to inundate and rain water overflow the banks of the landfill sites during the high intensity of rainfall within the short period. Heavy metals exist in the solid waste and leachate may have the potentiality to transfer to the food chain through the bio-accumulation of plants (Ukpong et al., 2013). Moreover, the toxic elements may lead to enter the body system through food, air and water over a period of time (Yahaya et al., 2009).

It is therefore essential to transform heavy metal bearing waste to a stabilised form to reduce contaminant leaching prior to land disposal (Navarro-Blasco et al., 2013). To treat the toxic wastes, US Environmental Protection Agency (EPA) has identified the stabilisation and solidification (S/S) technique as the best demonstrated available

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236 M.A. Hoque and M.A. Haque

technology (BDAT) for over 50 Resource Conservation and Recovery Act (RCRA) listed hazardous wastes (USEPA, 1993).This technologies are effective in treating a variety of difficult to manage waste materials for reuse or disposal which are not regarded as destructive techniques; rather, they eliminate or impede the mobility of contaminants. Cement-based S/S has been widely used in the world for about 50 years (Chen et al., 2009; Alunno and Medici, 1995; Conner and Hoeffner, 1998). It improves the handling characteristics and lower the leaching rates of wastes by a combination of solidification and stabilisation (Chen et al., 2009).The material used for S/S not only solidifies the hazardous waste by chemical means but also insolubilises, immobilises, encapsulates, destroys, sorbs, or otherwise interacts with the selected waste component (Malviya and Chaudhary, 2006b). Solidification refers to techniques that encapsulate the waste in a monolithic solid of high structural integrity (Omar et al., 2008). Contaminant migration is restricted by decreasing the surface area exposed to leaching or isolating the waste within an impervious capsule (USACE, 1995). Stabilisation induces chemical change in a waste to form insoluble compounds that entrap toxic elements or compound in an impervious polymer or stable crystal lattice. The combined effect of S/S is to prevent pollutants from migrating into the environment by making the toxic contaminants physically immobile or chemical bonding to the binders (Yusuf et al., 1995). The modified structure significantly reduces the leachability by decreasing the mobility of waste, thereby minimises the ground and surface-water contamination. This has always been a major consideration in the safe disposal of toxic wastes to land (Montgomery et al., 1998).

Apart from that the mix proportion of the binder and constituents of solidified matrix affect the release behaviour of toxic substance. While researchers are focusing on the solidification of waste for safe disposal to environment, it is also essential to justify the applicability for using the transformed solid waste in construction work as a potential resource keeping the environment pollution free.

Nonlinear leachate models have been evolving in the last decade for better understanding of experimental metal release behaviour from transformed solid matrix. In previous study, the polynomial equation-based leachate model was found to be applied for the representation of leaching mechanisms of heavy metals from radioactive waste-concrete composites (Plecas, 2003; Plecas and Dimovic, 2009, 2011). In addition, Plecas and Dimovic (2004) employed nonlinear leachate model successfully for the demonstration of copper aluminium oxychloride leaching mechanism from industrial waste-cement-bentonite clay matrix. The suitability of polynomial equation-based leachate model for explaining the leachate behaviour of heavy metals from solidified landfill waste is yet to be studied.

2 Materials and methods

2.1 Mixture preparation of solidified samples

Waste sample was prepared through air drying, blending and sieving (<2 mm diameter) them at room temperature (25°C). Haque et al. (2014) noted that the best possible compression strength of solidified matrix can be attained for a combination of 70% sand

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Optimising the mixing proportion of solidified landfill waste 237

and 30% waste where the cement to fine aggregate proportion was kept constant for their entire investigation. In current study, the same sand to waste proportion (7:3) was kept constant during the fine aggregate sample preparation, whereas the four types of solid mortar blocks with different mixing proportions of cement to fine aggregate (A = 1:1, B = 1:1.5, C =1:2 and D = 1:2.5) were used on their weight basis maintaining a constant water-cement ratios of 0.485. OPC having the type-I and 52.5 grade was used for block sample preparation. The mixing compositions of different ingredients used for the preparation of A–D samples are presented in Table 1.

Table 1 Mixing proportions of SWMB samples

Sample no. Cement (%) *Fine aggregate (%) Water-cement ratio

A (1:1) 50 50 0.485

B (1:1.5) 40 60 0.485

C (1:2) 33.33 66.67 0.485

D (1:2.5) 28.5 71.5 0.485

Note: *The proportion of sand to waste ratio = 7:3.

2.2 Unconfined compressive strength test

In this study, cubical block having the mould dimensions of 5 cm × 5 cm × 5 cm (Malviya and Chaudhary, 2006a) was prepared. After 24 hours, the cubical solidified blocks were unmolded and cured for 3, 7, 14, 21, and 28 days under the average humidity of 93% ± 2% at 25° ± 1°C in the laboratory. The pH of curing water was kept constant (pH = 7.0). Unconfined compressive strength test of samples were performed by using the ASTM method (C 109-93). Concrete compression machine B-ELE, M-ADR 2000KN was used for strength determination. Each test was performed three times to ensure the statistical significance of the experimental data. Average value of each test was presented in this study along with the standard deviation.

2.3 Leaching test for heavy metals

ANS 16.1 leaching test (Asavapisit et al., 2003) was used to observe the metal leaching pattern from solidified waste mortar block. Leaching tests were performed for 3, 7, 14, 21 and 28 curing days period. In this study, concentration of heavy metals like Fe, Cu, and Ni were measured. Fe and Cu were tested by using flame emission atomic absorption spectrophotometer (AAS) (Spectra AA Varian) and Ni was also measured using by Hach DR/4000 Spectrophotometer (using method: 8037).

Metal leaching test results were recorded in terms of released to the curing leachant. In this current study, percentage of immobilisation was determined by the metal entrapment within the solidified matrix during the curing periods (3, 7, 14, 21 and 28 days) in relation to the total availability of metal in waste mass of samples using the following mathematical expression (Malviya and Chaudhary, 2006a),

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238 M.A. Hoque and M.A. Haque

( )% 100leached availableD U U= ∗

In addition, release rate of heavy metals like Fe, Cu and Ni from waste matrix to the curing water was also calculated in terms of mg/day basis.

2.4 Leachate model

Nonlinear semi-empirical approach is a well-established method for modelling of metal leachate mechanisms from solid matrix (Plecas and Dimovic, 2005; Plecas, 2010). Similar model structure was used in this current study for the better understanding of migration phenomena of heavy metals such as Fe, Cu and Ni from solidified landfill waste block. The nonlinear model consists of third-term-based polynomial equation having the capability for describing long-term leaching characteristics of a solidified waste matrix [equation (1)].

1 20 1 2f A A t A t= + + (1)

SPSS software package was used for model calibration. The precision of the calibrated model profile was justified using statistical tools (R2, SSE, MSE and RMSE). In addition, the model parameters were estimated along with the calculation of 95% confidence interval for confirming the accuracy of the estimation process.

In this current study, it is therefore aimed to prepare paving blocks and design the optimum mixing proportion of stabilising binder (ordinary Portland cement) and fine aggregate for the achievement of desired compressive strength of the solidified waste block ensuring nominal heavy metal release from the solidified matrix. In addition, polynomial equation-based leachate model was justified through model calibration with experimental observation followed by model parameter estimation.

3 Results and discussions

In this current study, it was attempt to make the solidified landfill waste suitable for reusing the waste as paving blocks by mixing the waste with cement to entrap the heavy metals as well as to provide compressive strength to the waste block. Figure 1 represents the compressive strength test results of SWMB with different ratios of cement and fine aggregate. This study showed that all the mixing compositions A (1:1), B (1:1.5), C (1:2) and D (1:2.5) qualify the compressive strength standard (28-days) recommended by PWDB (2011) for paving blocks construction. At 28 days test, the highest compressive strength was achieved for the composition, A (3,712 psi) containing largest quantity of cement, whereas the compressive strength for the samples B, C and D were found to be 21.6 MPa, 19.2 MPa and 17.6 MPa respectively, giving the pattern of the reduction of strength with the reduction of cement content.

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Optimising the mixing proportion of solidified landfill waste 239

Figure 1 Unconfined compressive strength with different cement and fine aggregate ratios (see online version for colours)

This study revealed that the release of heavy metals from SWMB to leachant solution decreases with the increase of cement quantity in the solid block (Figures 2, 3 and 4). Among the four types mixing block samples, D block contains the lowest proportion of cement and results the highest heavy metal concentration in leachant solution for a curing period of 28 days. Though the quantity of Cu in leachant solution is insignificant, the concentration of Fe and Ni (2.11 mg/l and 1.13 mg/l respectively) at 28 days curing period exceeds the BECR (1997) standard for inland surface water quality disqualifying the composition D for sustainable paving block construction. On the other hand, the leaching concentration of Fe, Cu and Ni remain below the BECR standards for the rest mixing blocks A, B and C at 28 days curing period. The profile patterns (Figures 2–4) confirm the less quantity of metals to be released in leachant solution for the higher quantity of cement in the block. The block, A containing the proportion of cement to fine aggregate of 1:1 gives the best results where the leaching of the chemicals from the block cease early, however the composition C having the cement to fine aggregate ratio of 1:2 seems to be perfect for economical and sustainable paving block design.

Figure 2 Relation of collective Fe concentration in leachant solution with the curing period (see online version for colours)

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240 M.A. Hoque and M.A. Haque

Figure 3 Relation of collective Cu concentration in leachant solution with the curing period (see online version for colours)

Figure 4 Relation of collective Ni concentration in leachant solution with the curing period (see online version for colours)

Figure 5 Immobilisation and release rate of Fe in different curing days (see online version for colours)

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Optimising the mixing proportion of solidified landfill waste 241

Figure 6 Immobilisation and release rate of Cu in different curing days (see online version for colours)

Figure 7 Immobilisation and release rate of Ni in different curing days (see online version for colours)

The immobilisation pattern and release rate of Fe, Cu and Ni from all four types of paving blocks with different curing days were analysed and presented in Figure 5, 6 and 7 respectively. Before keeping the waste block in curing water, immobilisation or entrapment of metal contents was 100% within the four types of waste block. At three days curing period, immobilisation (%) of heavy metals within the solidified waste matrix was high but it decreases with the contact time of curing water. In this study, quite steady stable condition of immobilisation (%) was revealed at 28 days curing age (Figure 5, 6 and 7). Mixing composition A showed the highest immobilisation for three tested metals than the rest of the compositions as the cement contents decreases.

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242 M.A. Hoque and M.A. Haque

Figure 8 Model calibration using Fe release data [for mixing composition C (1:2)] (see online version for colours)

Figure 9 Model calibration using Cu release data [for mixing composition C (1:2)] (see online version for colours)

Figure 10 Model calibration using Ni release data [for mixing composition C (1:2)] (see online version for colours)

Table 2 Statistical evaluation of leachate model representing heavy metal release behaviour

Statistical parameters

Values obtained from model calibration Fe Cu Ni

R2 0.9993 0.9907 0.9924 SSE 3.1150 × 10–4 1.1438 × 10–4 9.6893 × 10–4 MSE 4.4500 × 10–5 1.6340 × 10–5 1.3841 × 10–4 RMSE 6.6708 × 10–3 4.0422 × 10–3 1.1765 × 10–2

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Optimising the mixing proportion of solidified landfill waste 243

Table 3 Estimated model parameters with 95% confidence interval

Fe

C

u

Ni

Para

met

er

Estim

ate

valu

e Lo

wer

bou

nd

Upp

er b

ound

Estim

ate

valu

e Lo

wer

bou

nd

Upp

er b

ound

Estim

ate

valu

e Lo

wer

bou

nd

Upp

er b

ound

A0

0.13

0836

0.

1026

1 0.

1590

–0.0

2797

9 –0

.045

0 –0

.010

8

–0.0

7136

5 –0

.121

1 –0

.021

5 A

1 0.

3937

08

0.37

30

0.41

43

0.

0673

29

0.05

48

0.07

98

0.

2525

05

0.21

61

0.28

88

A2

–0.0

3629

9 –0

.039

4 –0

.033

1

–0.0

0663

0 –0

.008

5 –0

.004

6

–0.0

2736

8 –0

.033

0 –0

.021

7

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244 M.A. Hoque and M.A. Haque

The heavy metals release rate at early stage of curing period is much higher for all types of block matrix studies [Figure 5, 6 and 7]. At first contacting curing test age like 3 day, highest release rate of metal contents was observed from waste matrix to the curing leachant. Decreasing release rate pattern of metals for all mixing compositions were found with the increases of curing age. Specific reason is that compressive strength of waste blocks increases with curing age. So, metal contents releasing tendency decreases with the increases of waste blocks compressive strength. The study observed that the rate is reduced to almost zero at 28 days curing period for the paving blocks A, B and C ensuring the encapsulation of metals in the solidified block matrix.

From this comprehensive study, the paving blocks A (1:1), B (1:1.15) and C (1:2) are found to be satisfactory meeting the desired compressive strength standard. However, the sustainability for the reuse of the product with the insurance of environmental safety as well as economical viability pointing out the mixing option C (having the cement to fine aggregate ratio of 1:2) as the optimum composition satisfying not only the desired compressive strength but also confirming a well encapsulation and proper immobilisation of metals in block matrix at 28 days curing period.

For a better understanding of the trend of metals transport phenomena the experimental observations were justified through nonlinear leachate model calibration process. The model calibration results for the cumulative release of Fe, Cu and Ni from solid waste mortar block having the mix proportion of 1:2 (cement to fine aggregate) are presented in Figure 8, 9 and 10 respectively. In every case, the model is found to be successful in explaining the experimental leaching behaviour of metal from the solidified matrix. The accuracy of the model calibration results was justified through statistical evaluation (Table 2). All the statistical parameters such as R2, SSE, MSE and RMSE give reasonable values confirming the reliability of the leachate model. Estimated model parameters with 95% confidence interval (Table 3) also confer the accuracy of the model calibration and parameter estimation process. The model is quite capable in demonstrating the trend of metals transport to the leachant solution with time. The model also confirms the steady state scenario of metals migration with a nominal release rate from solid blocks after 28 days of curing period ensuring the trend of ceasing of metals flow to the leachant solution (Figure 8, 9 and 10).

4 Conclusions

The prime intention of this study was to reduce the solid waste load at the dumping sites through sustainable reuse, thus to protect the soil, water and surrounding area from the toxic effect of heavy metals and apparent environmental pollution. Landfill waste containing heavy metals was solidified using stabilising binder and mixed with fine aggregate for the construction of paving blocks. For sustainable reuse of solidified solid waste, the constructed paving blocks were composed with different compositions of stabilising binder (i.e., OPC) and fine aggregate and undertaken to a comprehensive evaluation for compressive strength as well as the metals leaching behaviour analysis. From this current study the mixing proportion (cement to fine aggregate) of 1:2 with the waste to fine aggregate ratio of 3:7 is found to be optimum for paving block construction ensuring a satisfactory compressive strength of 2,748 psi at 28 days curing period. Moreover, the nominal heavy metal to be released from the solidified matrix was confirmed for the same paving block through leachate behaviour analysis where the

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Optimising the mixing proportion of solidified landfill waste 245

decreasing trend of the rate of release of heavy metals like Fe, Cu and Ni was clearly identified. In addition, the metal transport behaviour was justified using nonlinear leachate model which was successfully calibrated separately with collective Fe, Cu and Ni released data respectively. The model confers the ceasing trend of the release of heavy metals to the leachant solution after 28 days of curing period of the solidified waste mortar block, ensuring the full scale of immobilisation of heavy metals in the paving block to be required for sustainable civil engineering construction.

Acknowledgements

The authors would like to thank to the authority of Dhaka South and North City Corporations for the research grant to carry out this study at Matuail and Aminbazar landfill sites.

References Adjia, R., Fezeu, W.M.L., Tchatchueng, J.B., Sorho, S., Echevarria, G. and Ngassoum, M.B.

(2008) ‘Long term effect of municipal solid waste amendment on soil heavy metal content of sites used for periurban agriculture in Ngaoundere Cameroon’, African Journal of Environmental Science and Technology, Vol. 2, No. 12, pp.412–421.

Alpaslan, B. and Yukselen, M.A. (2002) ‘Remediation of lead contaminated soils by stabilization/solidification’,Water, Air and Soil Pollution, Vol. 133, Nos. 1–4, pp.253–263.

Alunno, R.V. and Medici, F. (1995) ‘Inertization of toxic metals in cement matrices: effects on hydration, setting and hardening’, Cement and Concrete Research, Vol. 25, No. 6, pp.1147–1152.

Asavapisit, S., Intarawong, S. and Harnwajanawong, N. (2003) ‘Leaching behavior of heavy metals from the solodified plating sludge under various leaching conditions’, Thammasat Int. J. Sc. Tech., Vol. 8, No. 1, pp.1–12.

BECR (1997) Bangladesh Environmental Conservation Rules 1997 [online] http://www.doe-bd.org/2nd_part/179-226.pdf (accessed 24 June 2013).

Bhalla, G., Swamee, P.K., Kumar, A. and Bansal, A. (2012) ‘Assessment of groundwater quality near municipal solid waste landfill by an aggregate index method’, International Journal of Environmental Sciences, Vol. 2, No. 2, pp.1492–1503.

Chen, Q.Y., Tyrer, M., Hills, C.D, Yang, X.M. and Carey, P. (2009) ‘Immobilisation of heavy metal in cement-based solidification/stabilisation: a review’, Waste Management, Vol. 29, No. 1, pp.390–403.

Conner, J.R. and Hoeffner, S.L. (1998) ‘The history of stabilisation/solidification technology’, Critical Reviews in Environmental Science and Technology, Vol. 28, No. 4, pp.325–396.

Haque, M.A. (2013) A Study on Solid Waste Solidification and Its Fitness to Use in Pavement Construction Ensuring the Release of Leachate Nominal through Dynamic Modeling, MSc Engg. thesis, Department of Civil and Environmental Engineering, Shahjalal University of Science and Technology, Bangladesh.

Haque, M.A., Hoque, M.A., Saha, S. and Hadiuzzaman, M. (2014) ‘Immobilization of heavy metals from paving block constructed with cement and sand-solid waste matrix’, Asian Journal of Applied Sciences, Science Alert, Vol. 7, No. 3, pp.150–157.

Page 13: IJEWM160305 HAQUE

246 M.A. Hoque and M.A. Haque

Hoque, M.A., Haque, M.A. and Mondal, M.S.A. (2014) ‘Seasonal effects on heavy metal concentration in decomposed solid waste of DNCC and DSCC landfill sites’, Horizon Research Publishing Corporation, Civil Engineering and Architecture, Vol. 2, No. 1, pp.52–56.

Longe, E.O. and Balogun, M.R. (2010) ‘Groundwater quality assessment near a municipal landfill, Lagos, Nigeria’, Research Journal of Applied Sciences, Engineering and Technology, Vol. 2, No. 1, pp.39–44, Department of Civil and Environmental Engineering, University of Lagos, Nigeria.

Malviya, R. and Chaudhary, R. (2006a) ‘Evaluation of leaching characteristics and environmental compatibility of solidified/stabilized industrial waste’, Journal of Material Cycles and Waste Management, Vol. 8, No. 1, pp.78–87.

Malviya, R. and Chaudhary, R. (2006b) ‘Factors affecting hazardous waste solidification/ stabilization: a review’ Journal of Hazardous Materials, Vol. 137, No. 1, pp.267–276.

Mamtaz, R. and Chowdhury, M.H. (2006) ‘Leaching characteristics of solid waste at an urban solid waste dumping site’, Journal of Civil Engineering (IEB), Vol. 34, No. 2, pp.71–79.

Montgomery, D.M., Sollars, C.J. and Perry, R. (1998) ‘Cement based solidification for the safe disposal of heavy metal contaminated sewage sludge’, Waste Management & Research, Vol. 6, No. 3, pp.217–226.

Navarro-Blasco, I., Duran, A., Sirera, R., Fernández, J.M. and Alvarez, J.I. (2013) ‘Solidification/stabilization of toxic metals in calcium aluminate cement matrices’, Journal of Hazardous Materials, Vol. 260, pp.89–103.

Oluyemi, E.A., Feujit, G., Oyekunle, J.A.O. and Ogunfowokan, A.O. (2008) ‘Seasonal variations in heavy metal concentrations in soil and some selected crops at a landfill in Nigeria’ African Journal of Environmental Science and Technology, Vol. 2, No. 5, pp.89–96.

Omar, F.R. M., Isa, M.H., Kutty, S.R.M., Malakahmad, A. and Adlan, M.N. (2008) ‘Solidification and stabilization of waste activated sludge from petroleum refinery’, International Conference on Environment 2008 (ICENV 2008).

Plecas, I. and Dimovic, S. (2004) ‘Immobilization of industrial waste in cement-bentonite clay matrix’, Bulletin of Material Science, Vol. 27, No. 2, pp.175–178.

Plecas, I. and Dimovic, S. (2005) ‘Immobilization of 137Cs and 60Co in concrete matrix. Part 2: Mathematical modeling of transport phenomena’, Annals of Nuclear Energy, Vol. 32, No. 13, pp.1509–1515.

Plecas, I. and Dimovic, S. (2009) ‘Mathematical modelling of immobilization of radionuclides 137Cs and 60Co in concrete matrix’, The Open Waste Management Journal, Vol. 2, pp.43–46.

Plecas, I. and Dimovic, S. (2011) ‘Mathematical modeling of transport phenomena in concrete matrix’, Scientific Journal of Physics, Chemistry and Technology, Vol. 9, No. 1, pp.21–27.

Plecas, I.B. (2003) ‘Comparison of mathematical interpretation in radioactive waste leaching studies’, Journal of Radioanalytical and Nuclear Chemistry, Vol. 258, No. 2, pp.435–437.

Plecas, I.B. (2010) ‘Mathematical modelling of immobilization of radionuclides 137Cs and 60Co in concrete matrix’, Progress in Nuclear Energy, Vol. 52, No. 7, pp.685–688.

PWDB (2011) Schedule of Rates for Civil Works, Concrete Hollow Block and Paving Stone, 13th ed., 196pp, Bangladesh.

Ukpong, E.C., Antigha, R.E. and Moses, E.O. (2013) ‘Assessment of heavy metals content in soils and plants around waste dumpsites in Uyo Metropolis, Akwa Ibom State’, The International Journal of Engineering and Science, Vol. 2, No. 7, pp.75–86.

USACE (1995) Engineering and Design Treatability Studies for Solidification/Stabilization of Contaminated Material, Department of the Army, US Army Corps of Engineers, UNEP, SWM, Washington, DC.

USEPA (1993) Solidification/Stabilization and It’s Applications to Waste Materials, EPA/530/R-93/012, Office of Research and Development, Washington, DC.

Page 14: IJEWM160305 HAQUE

Optimising the mixing proportion of solidified landfill waste 247

Yahaya, M.I., Mohammad, S. and Abdullahi, B.K. (2009) ‘Seasonal variations of heavy metals concentration in abattoir dumping site soil in Nigeria’, J. Appl. Sci. Environ. Manage., Vol. 13, No. 4, pp.9–13.

Yusuf, M., Mollah, A., Vempati, R.K., Lin, T.C. and Cocke, D.L. (1995) ‘The interfacial chemistry of solidification/stabilization of metals in cement and pozzolanic material systems’, Waste Management, Vol. 15, No. 2, pp.137–148.

Nomenclature

ANS American Nuclear Society f Cumulative amount of leached contaminant for each leaching period %D Percentage of heavy metal immobilisation within the solid waste block matrix OPC Ordinary Portland cement Uleached Quantity of heavy metal (mg/kg) leached out from the solid waste block matrix

in curing time Uavailable Quantity of heavy metal (mg/kg) available within the solid waste block matrix

in curing time PWDB Public Works Department of Bangladesh A0, A1 and A2 Model parameters R2 Coefficient of determination SSE Sum of square errors MSE Mean square error RMSE Root mean square error SWMB Solidified waste mortar block t Curing age (day)


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