Copper metallurgical slags are solid wastes resulting from the copper extraction process through pyrometallurgy. These granulated materials, dumped in the center of the city of Lubumbashi, contain certain “trace metal elements (ETM)” and/or “heavy metals” and are subjected to aerial leaching during the dry season, causing air pollution, and to leaching by rainwater, which leads to the contamination of the surrounding soil and surface water. The objective of this work was to use these slags, poor in recoverable elements (Cu, Co, Zn, Ge, and Ga), as fine aggregates for partial replacement of sand in concrete. The slags studied are of the ferrosilicate type belonging to the SiO2-FeO-CaO (MgO-Al2O3) system. They are completely vitreous, and their grain size distribution ranges from 0 to 3 mm. For this study, crushed sand with a granulometric distribution similar to that of the slags was chosen. The Bolomey method was used to optimize the sand content of the concrete as well as to calculate the optimum amount of water for concrete production. Once optimized, the sand was replaced with slag at respective rates of 0%, 25%, 50%, 75%, and 100% by weight. The compressive strengths of the hardened concretes based on these slags were measured at 1, 3, 7, 14, and 28 days of curing with a W/C (Water/Cement) ratio of 0.6. Slump tests of the fresh concrete were conducted to characterize the influence of sand replacement by slag on the concrete’s workability. The durability of the concrete with the optimized slag content was studied in corrosive solutions of HCl (5% wt), H2SO4 (3% wt), and Na2SO4 (1% wt). The results show the possibility of replacing crushed sand with slag up to a maximum rate of 50% by weight. The use of copper slag as sand decreases the cement’s water demand and therefore increases the value of the concrete’s mechanical strength. It was found that the optimum W/C ratio that allows for acceptable workability of the slag-based concrete is around 0.49. The durability study of the slag-based concretes in various corrosive solutions showed better performance of the slag-based concrete in the presence of H2SO4 and Na2SO4 solutions. Using the slag as a fine aggregate densifies the concrete structure, improves its workability by decreasing its W/C ratio, and increases its mechanical strengths while improving its resistance to corrosive environments.
References
[1]
International Energy Agency, World Business Council for Sustainable Development (2009) Cement Technology Roadmap 2009. Carbon Emissions Reductions up to 2050.
[2]
Numbi, B.K. (2013) Study of the Reactivity of Slag from Copper Smelting with a View to Its Use as a Cement Additive. Ph.D. Thesis, Ecole Polytechnique de Bruxeles, ULB. (In French)
[3]
Zhao, Q., Liu, X. and Jiang, J. (2015) Effect of Curing Temperature on Creep Behavior of Fly Ash Concrete. Construction and Building Materials, 96, 326-333. https://doi.org/10.1016/j.conbuildmat.2015.08.030
[4]
Shi, C., Meyer, C. and Behnood, A. (2008) Utilization of Copper Slag in Cement and Concrete. Resources, Conservation and Recycling, 52, 1115-1120. https://doi.org/10.1016/j.resconrec.2008.06.008
[5]
Scrivener, K.L., John, V.M. and Gartner, E.M. (2018) Eco-Efficient Cements: Potential Economically Viable Solutions for a Low-CO2 Cement-Based Materials Industry. Cement and Concrete Research, 114, 2-26. https://doi.org/10.1016/j.cemconres.2018.03.015
[6]
Al-Jabri, K.S., Hisada, M., Al-Saidy, A.H. and Al-Oraimi, S.K. (2009) Performance of High Strength Concrete Made with Copper Slag as a Fine Aggregate. Construction and Building Materials, 23, 2132-2140. https://doi.org/10.1016/j.conbuildmat.2008.12.013
[7]
Moura, W.A., Gonçalves, J.P. and Lima, M.B.L. (2007) Copper Slag Waste as a Supplementary Cementing Material to Concrete. Journal of Materials Science, 42, 2226-2230. https://doi.org/10.1007/s10853-006-0997-4
[8]
Gorai, B., Jana, R.K. and Premchand, (2003) Characteristics and Utilisation of Copper Slag—A Review. Resources, Conservation and Recycling, 39, 299-313. https://doi.org/10.1016/s0921-3449(02)00171-4
[9]
Al-Jabri, K.S., Taha, R.A., Al-Hashmi, A. and Al-Harthy, A.S. (2006) Effect of Copper Slag and Cement By-Pass Dust Addition on Mechanical Properties of Concrete. Construction and Building Materials, 20, 322-331. https://doi.org/10.1016/j.conbuildmat.2005.01.020
[10]
Caliskan, S. and Behnood, R. (2004) Recycling Copper Slag as Coarse Aggregate: Hardened Properties of Concrete. Proceedings of Seventh International Conference on Concrete Technology in Developing Countries, Singapore, 24-26 March 2023, 91-98.
[11]
Kabange, N. (2013) Etude de la réactivité des scories de la métallurgie du cuivre en vue de leur utilisation comme ajout au ciment. Ph.D. Thesis, Université Libre de Bruxelles.
[12]
Schlesinger, M.E., King, M.J., Sole, K.C. and Davenport, W.G. (2011) Overview. In: Schlesinger, M.E., et al., Eds., Extractive Metallurgy of Copper, Elsevier, 1-12. https://doi.org/10.1016/b978-0-08-096789-9.10001-0
[13]
Alter, H. (2005) The Composition and Environmental Hazard of Copper Slags in the Context of the Basel Convention. Resources, Conservation and Recycling, 43, 353-360. https://doi.org/10.1016/j.resconrec.2004.05.005
[14]
Li, Y., Perederiy, I. and Papangelakis, V.G. (2008) Cleaning of Waste Smelter Slags and Recovery of Valuable Metals by Pressure Oxidative Leaching. Journal of Hazardous Materials, 152, 607-615. https://doi.org/10.1016/j.jhazmat.2007.07.052
[15]
Carsi Kuhangana, T., Cheyns, K., Muta Musambo, T., Banza Lubaba Nkulu, C., Smolders, E., Hoet, P., et al. (2024) Cottage Industry as a Source of High Exposure to Lead: A Biomonitoring Study among People Involved in Manufacturing Cookware from Scrap Metal. Environmental Research, 250, Article ID: 118493. https://doi.org/10.1016/j.envres.2024.118493
[16]
Musa Obadia, P., Pyana Kitenge, J., Kayembe-Kitenge, T., Carsi Kuhangana, T., Kalenga Ilunga, G., Billen, J., et al. (2023) (125) Factors Associated with Erectile Dysfunction in Copper and Cobalt Miners: A Cross-Sectional Study in the Katanga Province, DR Congo. The Journal of Sexual Medicine, 20, qdad060.120. https://doi.org/10.1093/jsxmed/qdad060.120
[17]
Musa Obadia, P., Pyana Kitenge, J., Carsi Kuhangana, T., Kalenga Ilunga, G., Billen, J., Kayembe-Kitenge, T., et al. (2023) Erectile Dysfunction in Copper and Cobalt Miners: A Cross-Sectional Study in the Former Katanga Province, Democratic Republic of the Congo. Sexual Medicine, 11, qfad052. https://doi.org/10.1093/sexmed/qfad052
[18]
Kayembe-Kitenge, T., Kabange Umba, I., Musa Obadia, P., Mbuyi-Musanzayi, S., Nkulu Banza, P., Katoto, P.D.M.C., et al. (2020) Respiratory Health and Urinary Trace Metals among Artisanal Stone-Crushers: A Cross-Sectional Study in Lubumbashi, DR Congo. International Journal of Environmental Research and Public Health, 17, Article 9384. https://doi.org/10.3390/ijerph17249384
[19]
Muimba-Kankolongo, A., Banza Lubaba Nkulu, C., Mwitwa, J., Kampemba, F.M., Mulele Nabuyanda, M., Haufroid, V., et al. (2021) Contamination of Water and Food Crops by Trace Elements in the African Copperbelt: A Collaborative Cross-Border Study in Zambia and the Democratic Republic of Congo. Environmental Advances, 6, Article ID: 100103. https://doi.org/10.1016/j.envadv.2021.100103
[20]
Muimba-Kankolongo, A., Banza Lubaba Nkulu, C., Mwitwa, J., Kampemba, F.M. and Mulele Nabuyanda, M. (2022) Impacts of Trace Metals Pollution of Water, Food Crops, and Ambient Air on Population Health in Zambia and the DR Congo. Journal of Environmental and Public Health, 2022, Article ID: 4515115. https://doi.org/10.1155/2022/4515115
[21]
Mpulumba Badiambile, R., Musa Obadia, P., Useni Mutayo, M., Numbi Mukanya, J., Nkulu Banza, P., Kayembe Kitenge, T., et al. (2022) Metal Contaminants in River Water and Human Urine after an Episode of Major Pollution by Mining Wastes in the Kasai Province of DR Congo. ISEE Conference Abstracts, 2022. https://doi.org/10.1289/isee.2022.p-0872
[22]
Kayembe-Kitenge, T., Musa Obadia, P., Mbuyi-Musanzayi, S., Katshiez Nawej, C., Haufroid, V., Banza Lubaba Nkulu, C., et al. (2018) Cobalt and Thyroid Function. Case-Control Study of Patients with Goiters in Katanga, DR Congo. ISEE Conference Abstracts, 2018. https://doi.org/10.1289/isesisee.2018.p01.1810
[23]
Musa Obadia, P., Kayembe-Kitenge, T., Kyanika wa Mukoma, D., Carsi Kuhangana, T., Muta Musambo, T., Kasongo Tengwa, G., et al. (2018) Trace Metal Exposure and Health Effects among Urban Children Living in Areas with Different Degrees of Pollution in Lubumbashi, DR Congo. ISEE Conference Abstracts, 2018. https://doi.org/10.1289/isesisee.2018.p01.2040
[24]
Kayembe, T., Katoto Chimusa, P., Musa Obadia, P., Kalenga Ilunga, G., Katshiez Nawej, C., Nawrot, T., et al. (2019) Respiratory Health and Urinary Trace Metals among Artisanal Stone-Crushers: A Cross-Sectional Study in Lubumbashi, DR Congo. International Journal of Environmental Research and Public Health, 17, Article 9384.
[25]
Musa Obadia, P., Kayembe-Kitenge, T., Banza Lubaba Nkulu, C., Enzlin, P. and Nemery, B. (2019) Erectile Dysfunction and Mining-Related Jobs: An Explorative Study in Lubumbashi, Democratic Republic of Congo. Occupational and Environmental Medicine, 77, 19-21. https://doi.org/10.1136/oemed-2019-105771
[26]
Musa Obadia, P., Kayembe-Kitenge, T., Banza Lubaba Nkulu, C., Enzlin, P. and Nemery, B. (2020) P-02-7 Erectile Dysfunction and Mining-Related Jobs. an Explorative Study in Lubumbashi, Democratic Republic of Congo. The Journal of Sexual Medicine, 17, S174-S174. https://doi.org/10.1016/j.jsxm.2020.04.164
[27]
Al Jabri, K.S. (2006). Copper Slag as Fine Aggregate for High Performance Concrete. WIT Transactions on the Built Environment, 85, 9. https://doi.org/10.2495/hpsm06037
[28]
Al-Jabri, K.S., Al-Saidy, A.H. and Taha, R. (2011) Effect of Copper Slag as a Fine Aggregate on the Properties of Cement Mortars and Concrete. Construction and Building Materials, 25, 933-938. https://doi.org/10.1016/j.conbuildmat.2010.06.090
[29]
Shi, C. and Qian, J. (2000) High Performance Cementing Materials from Industrial Slags—A Review. Resources, Conservation and Recycling, 29, 195-207. https://doi.org/10.1016/s0921-3449(99)00060-9
[30]
Sarfo, P., Das, A., Wyss, G. and Young, C. (2017) Recovery of Metal Values from Copper Slag and Reuse of Residual Secondary Slag. Waste Management, 70, 272-281. https://doi.org/10.1016/j.wasman.2017.09.024
[31]
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, 29, 390-403. https://doi.org/10.1016/j.wasman.2008.01.019
[32]
Jin, Q. and Chen, L. (2022) A Review of the Influence of Copper Slag on the Properties of Cement-Based Materials. Materials, 15, Article 8594. https://doi.org/10.3390/ma15238594
[33]
Maharishi, A., Singh, S.P., Gupta, L.K. and Shehnazdeep, (2021) Strength and Durability Studies on Slag Cement Concrete Made with Copper Slag as Fine Aggregates. Materials Today: Proceedings, 38, 2639-2648. https://doi.org/10.1016/j.matpr.2020.08.232
[34]
Nainwal, A., Negi, P., Kumar Emani, P., Chandra Shah, M., Negi, A. and Kumar, V. (2021) An Experimental Investigation to Substitute Copper Slag in Concrete with Beas River Fine Aggregate. Materials Today: Proceedings, 46, 10339-10343. https://doi.org/10.1016/j.matpr.2020.12.481
[35]
Wu, W., Zhang, W. and Ma, G. (2010) Optimum Content of Copper Slag as a Fine Aggregate in High Strength Concrete. Materials & Design, 31, 2878-2883. https://doi.org/10.1016/j.matdes.2009.12.037
[36]
Gupta, N. and Siddique, R. (2020) Durability Characteristics of Self-Compacting Concrete Made with Copper Slag. Construction and Building Materials, 247, Article ID: 118580. https://doi.org/10.1016/j.conbuildmat.2020.118580
[37]
Brindha, D. and Nagan, S. (2011) Durability Studies on Copper Slag Admixed Concrete. Asian Journal of Civil Engineering, 12.
[38]
Kabange Numbi, B. (2013) Study of the Reactivity of Slag from Copper Smelting with a View to Its Use as a Cement Additive. (In French)
[39]
AFNOR (1990) NF P18-560, Aggregates, Particle Size Analysis by Sieving. French Standardization Association.
[40]
AFNOR (1990) NF P18-554, Measurement of Density, Porosity, Absorption Coefficient and Moisture Content of Chippings and Pebbles. French Standardization Association.
[41]
AFNOR (1990) NF P18-555, Aggregates, Density Measurements, Sands Absorption Coefficient and Water Content. French Standardization Association.
[42]
AFNOR (1990) NF P18-573, Aggregates Test of Los Angeles. French Standardization Association.
[43]
Dreux, G. and Festa, J. (1998) Nouveau guide du béton et de ses constituants. Eyrolles.
[44]
AFNOR (1981) NFP18-451, Concretes-Slump Test. French Standardization Association.
[45]
Selvi P, T. (2014) Experimental Study on Concrete Using Copper Slag as Replacement Material of Fine Aggregate. Journal of Civil & Environmental Engineering, 4, Article ID: 1000156. https://doi.org/10.4172/2165-784x.1000156
[46]
Mouli, M., Senhadji, Y., Benosman, A. and Khelafi, H. (2010) Résistance aux acides et à la pénétration des ions chlorures des mortiers avec pouzzolane et fine calcaire. Communication Science et Technologie, 8, 57-64.
