1. Introduction. In coal mining, gangues which are piled up on the surface after discharge pose a threat to the environment around mining areas [1], [2], [3], [4].Coal mining by solid backfill mining technology, as a green mining method was proposed to solve problems such as pressed coal and gangue deposition presented by traditional mining technologies [5], [6], [7].
Resource utilization of coal gangue Coal gangue sintered bricks Building materials Environmental restoration materials Power generation Ecological restoration of abandoned mine land Summary 13. Recent practices in mine tailings' recycling and reuse Introduction
Based on the problems of high carbon emission and high cost of traditional mining methods and filling materials, the tailings powder modified Coal Ganguebased Cementitious Backfill Material (CGCBM) was used for paste filling mining. In this study, the samples were prepared with different tailings powder content and different curing ages. The compressive strength test, XRD, SEM test, and NMR ...
The breakage and liberation of minerals are the key to fluidized mining for minerals. In the ball milling process, steel balls function as not only a grinding action implementer but also energy carrier to determine the breakage behavior of ores and the production capacity of the mill. When ground products present a much coarse or much fine particle size distribution, the separation process ...
Coal gangue, a solid waste generated during coal mining and washing, accounts for approximately 10%15% of the total coal production.
Analysis of Influencing Factors of Gangue Ball Milling Based on Multifractal Theory Lei Zhu 1, Wenzhe Gu 2,*, Fengqi Qiu 1 and Peng Zhang 1 1 China Coal Energy Research Institute, Xi'an 710054 ...
Sustainability 2023, 15, 6353 3 of 14 Test Apparatus and Procedure The model of the ball mill used in the test was a SM'500 500 mm test mill (Figure2), the power of the equipment was kW ...
However, few reports are documented that explain the crushing of coal gangue under the action of the crushing device. ... In the process of ball milling, gangue particle size is continuously reduced by the three interaction effects of impact, extrusion and friction with the grinding medium [46, 47]. While in ball milling, as the particle size ...
To reveal how CaF 2 improves the dissolution ratios of aluminum and iron ions in coal gangue, CaF 2 and hydrochloric acid are used to extract Al 3+ and Fe 3+ from the coal gangue calcined powder. The leaching ratios of Al 3+ and Fe 3+ are measured, and the filter residues are analyzed by BET, XRD, and SEM. The results show that adding 3% CaF 2 could increase the extraction ratio of Al 3+ from ...
Under normal circumstances, the coal gangue is massive, so coal gangue must be pretreated before in the preparation of porous ceramics. Including crushing, ball milling, sieving, acid leaching and other processes. This is to remove impurities from coal gangue and to improve the efficiency of the reaction.
In the process of ball milling, gangue particle size is continuously reduced by the three interaction effects of impact, ... Zhang Y, Ling T C. Reactivity activation of waste coal gangue and its impact on the properties of cementbased materialsa review[J]. Construction and Building Materials, 2020, 234: 117424.
The precise identification of damp, sticky coal gangue; efficient jet nozzle separation; and process layout in a narrow, restricted space are essential technologies for gangue source reduction based on underground gangue photoelectric separation, which is critical for the longterm growth of coal mines.
To study the heterogeneity and local heterogeneity of gangue particle size distribution (PSD) under ball milling, gangue from northern Shaanxi coal mine was taken as a research object.
Using coal gangue (CG) as supplementary cementitious materials (SCMs) is believed to be one of the effective strategies for CG disposal. ... 60, and 120 min, respectively. This evidences directly the effect of the wetmilling process that the pozzolanic reactivity of CG was enhanced after wetgrinding. Download : Download highres image (573KB ...
The particle size distribution of coal gangue after ball milling is shown in Figure 2. The ground coal gangue can increase the specific surface area of the particles, significantly improve the gel activity, and facilitate the dissolution of the reaction process, which is the basis for the preparation of geopolymers. ... Future research will ...
Design and implementation of coal gangue detection and recognition device. This study proposes an method for coal gangue detection and recognition on the basis of the DCNYOLOv3 algorithm. Firstly, the method collects realtime video images of a conveyor belt operation through an industrial camera erected perpendicular to the conveyor belt.
The results of the proximate analysis of coal gangue and the ash composition are listed in Table amounts of SiO 2, Al 2 O 3, and Fe 2 O 3 account for %, %, and % in the ash of coal gangue. Moreover, other impurities, such as TiO 2, MgO, and CaO, are also observed in small sum of the percentages of SiO 2 and Al 2 O 3 accounts for % of the total ash ...
Activation of coal gangue is necessary as kaolinite, the major aluminumcontaining component, is chemically inert. Thermal activation is a common method by which coal gangue has been activated that is simple to implement but relatively inefficient. The percentage recovery of alumina after thermal activation typically fails to reach 70% [8].
Abstract The amount of coal gangue, a byproduct of coal mining and washing, is rapidly increasing with the growing trend of energy consumption. The accumulated coal gangue without appropriate utilization has resulted in a squander of resources, waste disposal and environmental pollution issues.
Coal gangue is one of the industrial solid wastes that may harm the human body through the ecosystem for a long time. Using coal gangue in geopolymer preparation can effectively reduce cement output and meet the sustainability requirements. In this paper, the physical and chemical characteristics, including the heavy metal content, of coal gangue from different producing areas are described.
1. Introduction. Coal gangue is an industrial solid waste produced by coal mining and processing [13].The average production of gangue accounts for 1015% of raw coal production [4,5], making coal gangue one of the biggest solid wastes in present, utilization ratio of coal gangue can reach about 60% in some countries.
The mineral of coal gangue is mainly kaolinite, which can be used as mineral admixture after activation. In order to study the effect of coal gangue on the hydration process of concrete, 20% coal gangue powder was used to replace cement to prepare concrete. The phase composition, microstructure morphology and pore structure of concrete hydration products at different ages were observed by X ...
In mining, gangue ( / ɡæŋ /) [1] is the commercially worthless material that surrounds, or is closely mixed with, a wanted mineral in an ore deposit. It is thus distinct from overburden, which is the waste rock or materials overlying an ore or mineral body that are displaced during mining without being processed, and from tailings, which is ...
Introduction In recent years, with the largescale mining of coal resources, a large amount of coal gangue is produced and accumulated on the surface. Gangue has become a serious scientific and engineering issue in the current environment of green mining.
Consequently, the coalgangue recognition, i. e, detect the instantaneous refuse content of drawn coal and gangue mixture during top coal caving process, should be researched to realize the ...
After the ballmill grinding and calcination, CG powder particles are dense and smooth at the surface, with pores and prismatic shape. After heating, calcined CG powder becomes an irregular and porous structure, which may be caused by kaolinite hydroxylation and the phase change of the metakaolin. ... Preparation Process of Coal Gangue Powder ...
Afterwards, the underlying mechanisms about the effects of calcined gangue and wet comilling on the hydration process, strength development and microstructure evolution of PESCM were explored and discussed in depth. ... Utilization of solid waste highvolume calcium coal gangue in autoclaved aerated concrete: Physicomechanical properties ...
To study the heterogeneity and local heterogeneity of gangue particle size distribution (PSD) under ball milling, gangue from northern Shaanxi coal mine was taken as a research object. The multifractal pattern of PSD and the variation trend of characteristic parameters of gangue under different balltogangue ratios and grinding times were analyzed by introducing multifractal theory and ...
The results indicate that in the process of "jaw crushingball milling", gangue's particle size and shape fractal dimension values changed periodically. During the jaw crushing stage, the particle size fractal dimension increases with the width of the discharge opening, ranging from to
© DZCrusher - كل الحقوق محفوظة
