Study of the Internal Rebreaking Characteristics of Crushed …
The effect of particle size on the re-crushing characteristics of different lithological caving crushed gangues in mine goaf is investigated in this study based on …
16S rDNA Sequencing-Based Insights into the Bacterial …
1. Introduction. Coal gangue is a solid waste produced during coal mining, washing, and processing, accounting for about 10–20% of raw coal output [].According to incomplete statistics, China's coal gangue accumulates 40 billion tons, accounting for 120 km 2 or more, and continues to increase at speeds of 0.37–0.55 Gt per year and become …
Transparent characterization of spatial-temporal evolution of gangue …
The crushed coal gangue particles are widely used in solid backfilling. However, the nonuniform compaction and internal re-crushing behavior of crushed coal gangue under bearing stress have not yet … Expand
Optimizing the formulation of coal gangue planting …
Components of the planting substrate include coal gangue, sandy loam soil, fly ash, maize straw and water retention agents. The coal gangue was collected from Shangxinfang in the Mentougou District in Beijing. The particle size of the coal gangue was 1 cm–8 cm, and it was crushed to 50–100 mesh in the laboratory.
Soil characterization and differential patterns of heavy metal
Heavy metal pollution in the soil around coal gangue dumps is a threat to human health because it can be easily transferred into the human body through ingestion via the hand-to-mouth pathway, inhalation, and dermal contact (Yeganeh et al. 2013). Additionally, the long-term accumulation of heavy metal elements could result in a …
The Sustainable Utilization of Coal Gangue in Geotechnical …
Abstract. Among coal mining-related wastes, coal gangue (CG) is the heterogeneous waste generated during the mineral processing or coal washing phase of …
Influence of block shape on macroscopic deformation
When crushed gangue samples are loaded to ε = 0.4, for crushed gangue sample containing the single knife-shaped blocks, there is no significant "active triangle area" in the lateral displacement of the block, and there is the large lateral displacement of the sample from the top to the bottom; For crushed gangue samples containing the ...
Comparative study on mechanical and environmental
From 2010 to 2020, about 5 billion tons of coal gangue is produced in China [33]. Coal gangue heaping up for a long time in the natural environment has led to substantial land occupation, as well as the release of numerous minerals from the gangue into the soil, thereby engendering significant environmental contamination [34], [36].
Experimental Study on Confined Compaction Deformation of Crushed Gangue …
To prepare the crushed gangue samples with the gradation shown in Figure 2, first the crushed gangue was sieved into 10 particle size intervals by using the new standard soil sieve according to the particle size shown on the horizontal axis of Figure 2. Then, the particles in each particle size interval were blended according to the proportion ...
Preparation of coal gangue-slag-fly ash geopolymer …
After mixing, the activator was cooled to room temperature for at least 24 h before use. (3) Additive: Naphthalene water reducer. 2.2. Mechanical activation of coal gangue. First, large pieces of raw coal gangue were crushed into coarse aggregates with a jaw crusher and then crushed into fine aggregates with a hammer crusher.
Influence of coal gangue mulching with various thicknesses …
In particular, the chunks of raw soil were crushed using a rubber hammer before sieving. The coal gangue was crushed by using a steel hammer, after which it was mixed fully; then, four particle size groups were divided by using stainless steel sieves: 0–0.5 cm (P1), 0.5–1 cm (P2), 1–2 cm (P3), and 2–4 cm (P4).
Characterizations of macroscopic deformation and particle …
An equation for predicting stress-strain relationship during compression-induced deformation of gangue backfill materials under multi-factor coupling effects was established and shows that this equation can predict compression- induced deformation in goaf, beneficial to providing a basis for predicting strata movement and surface subsidence …
Heavy metals in soil from gangue stacking areas increases …
A large amount of coal gangue has accumulated on the earth's surface via air-soil exchange from contaminated air, dry/wet deposition, and surface runoff (Bandowe et al., 2018; Jiang et al., 2014), releasing several toxic and harmful substances (polycyclic aromatic hydrocarbons, trace elements, heavy metals, and other organic pollutants) into ...
An experimental investigation into the compaction
The main chemical component in gangue, SiO 2, is inert and can act as the framework in backfilling body.Meanwhile, the active CaO and Al 2 O 3 in the gangue can be hydrated with cement, fly ash, and lime, to form Ca(OH) 2, insoluble calcium silicate hydrate and calcium aluminate hydrate gel.Ca(OH) 2 in return contributes to the hydration …
Study on mechanical properties of coal gangue and fly ash
Liqiang Ma & Jintao Wang. 171 Accesses. Explore all metrics. Abstract. Backfill mining can effectively alleviate the problems of surface collapse and ecological …
Study on the macro–micro evolution of compaction
In the current research, a large number of studies have been carried out on the compressive macroscopic deformation characteristics of crushed gangue, and its …
Influence of coal gangue mulching with various thicknesses …
We hypothesized that the coal gangue mulching on the surface of soil columns can change the movement of water on the soil surface, thereby affecting the …
Study on the propagation characteristics of methane-air
The explosion scene in gob was simplified and the position of the crushed gangue from the ignition source was set to 0.5 m, the actual setup is shown in Fig. 3.The gangue used in the experiments ...
Residual deformation of coal gangue subgrade filler under …
Residual deformation models are generally divided into two ... static responses of crushed stone, coarse-grained soil and subgrade filler. ... and particle crushing of crushed gangue particle ...
Environmental-friendly coal gangue-biochar composites …
Biochar was prepared using a tube furnace under 450 °C and 700 °C, respectively. For the preparation of CG-biochar, the coal gangue is crushed into less than 2 cm by a crusher, and then ball-milled for 3 h with water. After ball milling, it is dried at 80 °C, and the agglomerated coal gangue powder is fully ground into powder.
Diffusion law of coal gangue slurry and the application of …
Lay the gangue particles screened before the test into the test box with a thickness of 20 cm and a length of 200 cm. Weigh and prepare a large amount of slurry, adjust the inclination angle of ...
Sustainable and clean utilization of coal gangue: …
Sun et al. [24] activated a mixture of coal gangue and straw in KOH and H2O2 solutions to prepare silicon fertilizer, but the Si that was finally available in the activated coal gangue was only approximately 1.0–3.5%; it is thus dificult to prepare high-eficiency silicon fertilizer using chemical activation.
Experimental Study on Confined Compaction …
Aiming at the problem of the confined compaction deformation of crushed gangue, this paper studied the relationship between the compaction deformation of crushed gangue and the axial stress, water …
Processes | Free Full-Text | Experimental Study and …
From the perspective of resource recovery and environmental protection, coal gangue-fly ash cemented backfill coal mining has become an important direction for the green development of coal mines in recent years. Analysis of the rheological parameters of backfill slurry is the basic principle to design a backfill pipeline system. Coal gangue-fly …
Characterizations of macroscopic deformation and particle crushing …
The stability of the gangue rib and the movement of the overlying strata are significantly influenced by the compressive deformation characteristics of crushed stones. In this research, a large gangue rib similar compression device was designed to perform compression tests on gravel of different particle sizes.
Technology and engineering test of filling goaf with coal gangue …
Firstly, the gangue from the coal washing plant is crushed into powder with a certain particle size and added with water and additives to produce a 70.0% concentration of gangue slurry at the ...
A potential way for improving the dispersivity and …
The experimental soil utilized Yang ling District's soil (YL soil) as the raw material. The YL soil was dispersed by adding 0.18 % Na 2 CO 3 [20].Natural dispersive soil directly used in the test would introduce more interference factors, so in this study, natural dispersive soil was only used as a comparison to prove that calcined coal …
(PDF) Experimental Study on the Preparation of Improved Soil …
The experimental results showed that the best proportion of soil matrix improvement was 42.9% coal gangue, 7.1% fly ash, 10% straw and 40% soil, where the coal gangue particle size proportion was ...
The 3D reconstruction of a digital model for irregular gangue …
Particle flow simulation of broken gangue backfill materials can be used to effectively study the bearing-compression characteristics of gangue backfill materials. The 3D reconstruction of the digital model for the real shape of the irregular gangue blocks is crucial for the numerical simulation of particle flow to accurately express the spatial and …