Added: May 25, 2022
Last edited: May 25, 2022
Mining is the most important source of all the raw materials used to build and power up our modern societies, ranging from metals such as iron and aluminum used for the Construction of automobiles and other machinery, steel used for heavy construction works, Uranium used as fuel for power plants, and lithium and nickel used for making smartphone batteries. The pace at which the global population is growing, and technology is evolving, continuously calls for more and more extraction of these mineral resources in order to satisfy the ever-growing global needs. However, these resources are finite, and their extraction Comes at a cost to the environment; so, scientists are obliged to look towards more sustainable and practical ways of supplying these resources without compromising the environment or future generations. One of the ways forward is to use tailings sands and mine waste rock aggregates for construction works, thereby reducing the need to mine new resources (sand). Sand on the other hand which is a non-renewable resource and is the is the second most extracted natural resource after water by volume used in almost all sectors of development such as construction and manufacturing processes constitutes 85% of material mined from the earth. Despite the importance of sand, the illegal, unsustainable overexploitation in developing countries possesses a huge threat to ecosystems and community. To solve this problem, tailings sand and other mines wastes aggregates hold the potential of being used for construction purposes for example construction of houses, embankments, Pavements and other related infrastructure
The main type of mining carry out in most African cities is artisanal mining which involve the removal of overburden material from the ore deposit to the surface which in most cases it’s being abandoned without any rehabilitation after mining. Tailings are traditionally stored in ponds surrounded by Tailings dams (Mahmood and Mulligan, 2010) and Lands occupied by tailings dams loss their original value, and generally degrade with time (Gayana and Chander, 2018). This tailing there poses a huge environmental. Despite the importance of sand, the illegal, unsustainable overexploitation in developing countries possesses a huge threat to ecosystems and community. To solve this problem, tailings sand and other mines wastes aggregates hold the potential of being used for construction purposes
The benefits of using tailings sands are multi-faceted;
financial, environmental and socioeconomic. These are;
Firstly, it is a more sustainable mining practice, than the construction of tailings dams. Tailings dams occupy huge areas of land, and ultimately deplete them. Secondly, tailings dams constitute a major environmental hazard. The failures of various tailings dams have proven to be very devasting, both to man and the environment. The acquisition of tailings sand and crushed waste rock from mines is easier and more cost effective than dredging or
quarrying. Finally, the use of tailings sands and waste rock from mines, reduces the need to extract these materials from the earth, and thus prevents the disturbance of ecosystems in such environment.
The outcome is sand produce from mine tailings and other construction materials like concrete and bricks. The process of production is as follows:
Firstly, research is done on the properties of tailings materials and suitability for various uses, properties include tendency to disintegrate or weather which is not good for construction, high strength sand tailing is strongly recommended for construction and lastly sand tailing with high elastic modulus is strongly recommended for construction. Secondly, information about tailings sands and other waste
rock materials is determined for example tailing sand derived from parent rock with fine to medium grain sizes such as fine sandstone,basalt,quartzite and gneiss are suitable for construction .The next step is to dewatered the tailing sand by drying under the sun, or using a sand dewatering screen. After dewatering, the sand can be sieved to obtain the desired grainsized fragments while the remaining material which is mostly use to make backed bricks and Concrete. The sand is then mixed with crushed rock aggregates and cement, to produce concrete, for construction
Waste as resource
Construction sector
mining