scholarly journals Recovery of Mining Wastes in Building Materials: A Review

2021 ◽  
Vol 11 (04) ◽  
pp. 379-397
Author(s):  
Alinabiwe Nyamuhanga Ally ◽  
Manjia Marcelline Blanche ◽  
Ursula Joyce Pettang Nana ◽  
Masika Muhiwa Grâce ◽  
Ngapgue François ◽  
...  
2019 ◽  
Vol 69 (336) ◽  
pp. 199 ◽  
Author(s):  
B. J. Frasson ◽  
R. C.A. Pinto ◽  
J. C. Rocha

Coal mining wastes are associated with serious environmental problems; they have potential as building materials, including alkali-activated cement. In this study, the effect of different coal mining wastes on the mechanical properties and microstructural development of alkali-activated materials (AAMs) was evaluated through XRD, SEM and FTIR spectroscopy. Different alkali-activated compounds were produced; the alkaline solution was composed of NaOH+Na2SiO3. The results obtained using the calcined coal sludge showed excellent mechanical performance, with compressive strength higher than 60 MPa. However, addition of metakaolin and ordinary Portland cement was necessary to increase the mechanical performance of calcined coal gangue materials. The formation of N-A-S-H gel and the incorporation of iron ions into the cementitious matrix were evidenced. Ultrasonic pulse velocity indicated the early polymerization during the reaction processes. The study verified that the different characteristics of the wastes influence the performance of alkali-activated materials.


Minerals ◽  
2018 ◽  
Vol 8 (11) ◽  
pp. 503 ◽  
Author(s):  
Elena Kalinkina ◽  
Basya Gurevich ◽  
Alexander Kalinkin

Antigorite is a very common rock-forming mineral and it is often present in mining wastes. Utilization of these wastes is a very important issue from the environmental point of view. A potential use for mining wastes is for the production of building materials. This study investigated the alkali activation of antigorite and antigorite-containing ore dressing tailings (AT) milled in a planetary ball mill in an air or CO2 atmosphere. The specific surface area, amorphisation, and dehydroxylation of milled antigorite and AT were examined, and their effect on the cementitious properties was investigated. Binders were prepared by mixing the milled antigorite or AT with liquid glass and curing at 20 ± 2 °C in dry (relative humidity of 65 ± 5%) or humid (relative humidity of 95 ± 5%) conditions for up to 28 days. Curing at dry conditions was found to produce binders with increased strengths. The compressive strength of the alkali-activated binder also increased with increased milling time. For AT milled in air for 4 min and cured in dry conditions for 28 days, the compressive strength was 49 MPa. The milling atmosphere (air or CO2) influenced the cementitious properties of the alkali activated binder to a small extent.


Author(s):  
J. R. Millette ◽  
R. S. Brown

The United States Environmental Protection Agency (EPA) has labeled as “friable” those building materials that are likely to readily release fibers. Friable materials when dry, can easily be crumbled, pulverized, or reduced to powder using hand pressure. Other asbestos containing building materials (ACBM) where the asbestos fibers are in a matrix of cement or bituminous or resinous binders are considered non-friable. However, when subjected to sanding, grinding, cutting or other forms of abrasion, these non-friable materials are to be treated as friable asbestos material. There has been a hypothesis that all raw asbestos fibers are encapsulated in solvents and binders and are not released as individual fibers if the material is cut or abraded. Examination of a number of different types of non-friable materials under the SEM show that after cutting or abrasion, tuffs or bundles of fibers are evident on the surfaces of the materials. When these tuffs or bundles are examined, they are shown to contain asbestos fibers which are free from binder material. These free fibers may be released into the air upon further cutting or abrasion.


Author(s):  
Mykhailo Kosmii ◽  
Vasyl. Kasiianchuk ◽  
Ruslan Zhyrak ◽  
Ivan Krykhovetskyi

The purpose of this paper is to analyze and research the legal mechanisms which make it possible to improve agroecology through the organization of cultivation of Jerusalem artichoke.Methodology. The methodology includes comprehensive analysis and generalization of available scientific, theoretical, practical and applied material and development of relevant conclusions and recommendations. During the research, the following methods of scientific cognition were used: dialectical, terminological, historical and legal, logical and normative, systemic and structural, functional, normative and dogmatic, generalization methods. Results. The process of analysis and research highlighted the possibilities of cultivating Jerusalem artichoke for improving agroecology, namely improving the ecological state of the atmosphere air and soil, preparing them for organic farming. The article contains examples of practical application of tubers of Jerusalem artichoke and herbage for the production of therapeutic and prophylactic products, alternative energy and highly efficient building materials. Scientific novelty. The study found that the authors summarized and systematized the levels of legal regulation in the field of using Jerusalem artichoke for improving agroecology, preparing soil for organic farming, in particular: the inter-sectoral level which covers the interaction of agricultural and environmental law in terms of cultivation and use of Jerusalem artichoke; the level of integrated environmental and legal regulation; level of individual resource (floristic) legal regulation; the level of environmental protection (anthropoprotection) legislation.Practical importance. The results of the study can be used in law-making and environmental protection activities related to issues of cultivating and using the Jerusalem artichoke as a means of improving agroecology.


2005 ◽  
Author(s):  
J. Martyny ◽  
K. Pacheco ◽  
R. Harbeck ◽  
E. Barker ◽  
M. Sills ◽  
...  

2004 ◽  
Author(s):  
L. Saarinen ◽  
T. Tuomi ◽  
T. Johnsson ◽  
K. Reijula
Keyword(s):  

2015 ◽  
Vol 1 (5) ◽  
pp. 250-254
Author(s):  
Adriana Eštoková ◽  
Alena Luptáková ◽  
Martina Kovalčíková ◽  
Nadezda Stevulova

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