Explosives Engineering Commons^™

Magnetic And Optical Properties Of Airborne Dust Particles Nearby Coal-Fired Power Plants In Upper Silesia, Poland: A Mineralogical, Petrographical And Chemical Approach, Chrysoula Chrysakopoulou, Konstantinos Perleros, Małgorzata Wojtaszek-Kalaitzidi, Lambrini Papadopoulou, Nikolaos Kantiranis, Stavros Kalaitzidis

Journal of Sustainable Mining

Coal mining and exploitation pose certain challenges in terms of environmental management. The objective of this research is the study of airborne dust from Knurow region, Southern Poland, aiming to identify the level and the features of anthropogenic particles, mostly in the form of fly ash. Two samples collected from a domestic gutter system were analysed regarding their mineralogical, chemical and petrographical features, emphasizing the magnetic fraction and the carbonized organic particles. The airborne dust contains 22 wt.% of fossil and fresh organic matter, whereas the major mineralogical phase is magnetite. The magnetic fraction (up to 3 wt.%) appears in …

Leveraging Intrinsic Properties For Classification Of Coal Seams Towards Spontaneous Combustion Proclivity And Predicting Susceptibility Using Machine Learning: Smart And Sustainable Mining Approach, Siddhartha Agarwal, Pradeep K. Gautam, Yuhao Zou, Rishabh Dwivedi, D.C. Panigrahi, C. Dagli, Atul Singh

Journal of Sustainable Mining

Mine fires and other hazards caused by spontaneous coal combustion are a pervasive and longstanding issue in Jharia coalfields, India. This study proposes a novel approach to classify coal seams based on their propensity to spontaneous combustion using the intrinsic properties of 30 coal samples from different seams. This method eliminates the need for expensive and time-consuming experimental determinations of susceptibility indices (SI) such as crossing point temperature (CPT), critical air blast (CAB), and differential thermal analysis (DTA). All clustering models, viz. hierarchical, k-means, and multidimensional scaling, aptly classify coal seams into three categories: highly risky, medium risky, and low …

Spatio-Temporal Changes In The Gravity And Post-Mining Seismic Activity In Abandoned Deep Coal Mine Kazimierz-Juliusz During Flooding, Andrzej Kotyrba, Łukasz Kortas, Sławomir Siwek

Journal of Sustainable Mining

The flooding of an underground hard coal mine, resulting in the filling of post-mining voids (workings and goafs) and the repeated saturation of pore and interstitial spaces of the adjacent rock with water, change the mass and its distribution in the near-surface part of the earth’s crust. This process is slow and lasts many years. As a result, the local gravity field undergoes dynamic changes. It depends on the surface morphology and the density of geological strata, which is related to their water content. Changes in the local gravity field can be monitored by periodic gravity surveys performed in the …

Gravity Field Changes During Deep Exploitation Of The Coal Longwall And Their Relation To Stress Distribution And Seismic Activity, Łukasz Kortas

Journal of Sustainable Mining

Mining operations cause volumetric deformations within the rock mass and changes in its density, to which the gravimetric method is sensitive. These changes are particularly well seen in periodic measurements of the local gravity field. The paper analyses the relationship between the movement of a longwall in a coal seam and the change in the distribution of the gravity field in time and space observed on the ground surface. Relative gravimetric measurements were carried out in six series between 2018 and 2020; before the start of coal extraction, with the progress of the longwall and after the cessation of mining. …

Impact Of Nanobubbles On Mechanical Coal Flotation Process, Ahmed Sobhy, Dongping Tao

Mining Engineering Faculty Research & Creative Works

A bank of three 10-liter mechanical flotation cells integrated with nanobubble technology was investigated to assess the impact of nanobubbles on coal separation performance at different operating variables. The most significant operation parameters such as fuel oil collector dosage, methyl isobutyl carbinol (MIBC) frother concentration, flow rate to nanobubble generator, feed solid concentration, and feed flow rate were studied individually. Nanobubbles are generated selectively on the hydrophobic particles, which should have a positive effect on flotation separation efficiency. It has been shown that frother concentration, collector dosage, and flow rate to nanobubble generator had a positive and significant effect on …

Nanobubble Column Flotation For More Efficient Coal Recovery, Ahmed Sobhy, R. Honaker, D. Tao

Mining Engineering Faculty Research & Creative Works

Froth flotation is a widely used, cost effective coal cleaning process. However, its high process efficiency is limited to a narrow particle size range between approximately 50 to 600 μm for coal and 10 to 100 μm for minerals. Beyond this range, the efficiency of froth flotation decreases sharply, especially for difficult-to-float coal fines of weak hydrophobicity (e.g., oxidized coal).

This study was aimed at enhancing recovery of an Illinois fine coal sample using a flotation column featuring a hydrodynamic cavitation nanobubble generator. Nanobubbles that are mostly smaller than 1 μm can be formed selectively on hydrophobic coal particles from …