Mineral processing and characterization of coal waste to be used as fine aggregates for concrete paving blocks

Abstract

Commercial coal production in the southern region of Brazil has been occurring since the beginning of the twentieth century. Due to the geological characteristics of the region, large amounts of solid wastes are generated. The aim of this work was to evaluate the use of coal waste to produce concrete paving blocks. A procedure to process the coal waste with the purpose of reducing the sulfur content and changing the particle size distribution of the material to meet the specification of fine aggregates was developed. The methodology considered the following steps: (a) sampling of a coal mining waste; (b) gravity separation of the fraction with specific gravity between 2.4 and 2.8; (c) comminution of the material and particle size analysis; (d) technological characterization of the material and production of concrete paving blocks; and (e) acidity generation prediction (environmental feasibility). The results showed that the coal waste considered in this work can be used to replace conventional sand as a fine aggregate for concrete paving blocks in a proportion of up to 50%. This practice can result in cleaner coal production and reduce the demand for exploitation of sand deposits.

Evaluation of the incorporation of charcoal residues in cement mortars

“…By‐products of the agroindustry can be studied, aiming to use mineral additions in cementitious matrices (Rossignolo et al., 2017). Some recent examples that can be cited in different countries of agroresidues for partial replacement of cement or sand in conventional concrete, compacted concrete, and filling concrete: Different types of residues of agroproducts: cork powder, Portugal (Ramos et al., 2014); date palm waste, Saudi Arabia (Nasir & Al‐Kutti, 2019); palm oil fly ash, Russia (Faridmehr et al., 2021); Rice straw residues: Thailand (Sua‐Iam & Makul, 2013); USA (Venkatanarayanan & Rangaraju, 2014); Pakistan (Abbas, 2017); Bénin (Chabi et al., 2018); Wood ash: Sri Lanka (Subramaniam et al., 2015); USA (Yang et al., 2016); India (Batt & Garg, 2017; Chowdhury et al., 2015); Lithuania (Skripkiūnas et al., 2017); Sugarcane bagasse ash: India (Dhengare et al., 2015; Reddy et al., 2015); Brazil (Almeida et al., 2015; Moretti et al., 2018; Rossignolo et al., 2017); Mexico (Landa‐Ruiz et al., 2021); Charcoal residue: Sub‐Saharan Africa (Mwampamba et al., 2013); Brazil (Beline et al., 2015; Bortoletto et al., 2017; Mota et al., 2017; Ramos, 2015; Reis, 2019; Santos et al., 2015). …”

Utilization of Recycled Coal Mining Waste for Road Foundation Layers in Vietnam

“…In China, the amount of coal mining waste (CMW) was 315 million tons for underground coal mining [3]. Therefore, the recycling of industrial wastes as construction materials has been interested in many countries to minimize the environmental impacts caused by the landfill area [4], as well as replacing the natural aggregates for the construction industry [3,[5][6][7][8][9][10][11][12]. Indranratna et.…”

Optimizing the tensile strength of concrete containing coal waste considering the cost

“…In this regard, several researchers have used coal mining wastes [40][41][42], fly ash [21,36], bottom ash [1,16,20,38,47,48], Pond ash [55], coal ash [18,37]; slag products [58], coal mine overburden [19], copper slag [2,7], blast furnace slag [45,56], steel fibers [6], waste ceramic tile [52] and recycled plastic [39,46] as an alternative of concrete components.…”