Currently, there are three natural radioactive series (uranium, ... coal gangue identication technology by natural gamma-ray. ... followed by sandstone at 30.9%, while conglomerate and limestone
To investigate the optimal ratio of all components of the coal gangue planting substrate, we designed and implemented four-factor orthogonal experiments, each at three- levels (Table 2).These orthogonal experiments produced nine different component ratios, as shown in Table 3 (Yin et al., 2016; Li et al., 2017); sandy loam soil was used …
The leaching kinetics of alumina extraction from coal gangue with hydrochloric acid was investigated. ... at a calcination temperature of 700 °C [24]. The dissolution rate of alumina can be greatly improved by adding limestone during calcination; furthermore, sodium carbonate can react with coal gangue to form nepheline during …
We were interested to elaborate a Portland clinker from mixtures composed of limestone and coal gangue. A preliminary study was focused on the optimization of the composition of the mixture ...
The analysis of coal and gangue characteristics throughout the development of separation systems leads to different work implementation directions, some separation systems perform image geometric ...
Hg exhibited different characteristics in its mean concentrations than Cd. The highest mean concentration (0.1 mg/kg) was found in coal gangue, whereas soil and diorite samples had low mean concentrations (0.02 mg/kg and 0.01 mg/kg, respectively). High Hg concentrations (0.3 mg/kg–6.3 mg/kg) in coal gangue were also found by Niu et al. …
2.1 Materials. The coal gangue was obtained from a coal gangue power plant located in Shuozhou, Northern China (N 39.51°, S 112.29°). Plant ash was obtained from the leaves of polar plant (Populus L.), which was burned completely in the air.The mineral composition of the coal gangue and plant ash determined by XRF spectrometry …
transform to suppress the speckles in the gangue images, to enhance edges, because the coal gangue images were always contaminated with speckles of coal dust [8]. Ma and Zang suggested a novel image processing method for separating gangues from coal with wavelet analysis. The Haar wavelet was used to reduce high fre-quent noises of gangue …
Coal gangue, as a type of solid waste discharged during coal mining and coal washing, occupies a large amount of land resources owing to accumulated gangue, which eventually results in ecological ...
The utilization of calcined coal gangue (CCG) and limestone for the preparation of blended cement is an efficient approach to address the issue of coal gangue disposal. However, the compressive strength development of blended cement is slow, …
With the long-term sustained development of coal resources, the continuous underground coal mining activities have caused surface subsidence and accumulation of coal gangue waste, which has ...
Coal gangue, produced during coal mining and processing [1, 2], is one of the most extensively produced solid wastes in China [1, 3], accounting for approximately 10%‒20% of raw coal production [].The accumulation of coal gangue causes serious environmental, social, and economic problems in the coal mining area [].Heavy metals …
limestone, the replacement level can reach 30% (20% Calcined coal gangue and 10% limestone). Therefore, studies on using the suspended calcination technology for the preparation of metakaolin by
The reuse of coal gangue for energy recovery is developing rapidly in China, due to its advantage in achieving both economic and environmental benefits. Low-quality coal is often added to elevate the calorific value of the fuel. In this paper, the combustion characteristics as well as pollutant emissions (SO2 and NO) of coal …
Gangue, a typical waste associated with the coal mining process in northern China, was characterized before and after thermal treatment by XRF, XRD, TGA-DSC, and SEM. The pozzolanic reactivity of calcined gangue with different calcined temperature was tested by standard mortar strength and R3 calorimetry test. The performance of blended cement …
Influence of kaolinite content in coal-series metakaolin and soft metakaolin on the performance of cement blends with and without limestone. ... However, a significant strength loss (~33.6%)...
So far, many scholars have done a lot of work on water pollution caused by wastewater discharged during the process of coal mining [19], but there is less research about the impact of coal gangue ...
coal-gangue-based silicon fertilizer, and its reliability veri-ed, thereby providing a theoretical basis for use of coal-gangue-based silicon fertilizer in agriculture. Materials and methods Materials Coal gangue The coal gangue used in the experiment comes from the Shendong mining area in Inner Mongolia, China, with an ash content of~ 85.60%.
2.2. Experiment procedures2.2.1. Thermal treatment. The treatment process for the original coal gangue involves three sequential steps: (1) the raw coal gangues were crushed to achieve a size of no more than 20 mm; (2) the crushed coal gangue powder underwent a 24-hour high-temperature drying phase at 80°C until it reached a constant …
1. Introduction. Coal gangue, a waste produced during coal mining, has been regarded as the largest source of industrial waste in China. It is estimated that the production of 1 t coal generates 0.1–0.25 t coal gangue [1], and the total stockpile of coal gangue exceeds 6 billion tons in China [2], [3].The coal gangue not only occupies …
The coal gangue sample was separated to reduce coal content based on the density by calculating volume and weight of the ores. The other raw materials used for this study include PI cement (CEM I 42.5 N), gypsum, and limestone with their chemical …
Abstract Among coal mining-related wastes, coal gangue (CG) is the heterogeneous waste generated during the mineral processing or coal washing phase of coal mining. A thorough understanding of environmental concerns associated with the current model of ...
The selected coal gangue is mainly muddy rock, with as little sandstone content as possible. The production of cement from coal gangue requires "two grinding and one burning"： 1 Mix the crushed coal gangue and limestone in a certain proportion and use a coal mill to grind them into fine materials.
The separation of coal and gangue is an important aspect of coal production, which can improve coal quality, save energy, reduce consumption, and enable the rational use of resources. At present, manual selection remains widely implemented, but the working environment is harsh, labour intensity is high, and efficiency is low.
We investigated the possibility of recycling and recovery of Moroccan coal gangue (coal mine of Jerada). The analysis of the waste showed that it is formed essentially of silica and clays. We were interested to elaborate a Portland clinker from mixtures composed of limestone and coal gangue. A preliminary study was focused on the optimization of the …
Ore sorting is a useful tool to remove gangue material from the ore and increase the quality of the ore. The vast developments in the area of artificial intelligence allow fast processing of full-color digital images for the preferred investigations. The associated gangue minerals from limestone and coal mines were identified using three different approaches.
The comparison of this coal gangue to the usual clays shows that it is richer in silica and alumina, but poorer in calcium and iron oxides. 3.1. Optimization of the mixture limestone-gangue For each mixture, we studied the changes in the three criteria values when changing the percentage of gangue in the mixture limestone-gangue.
A series of soil indicators that can be affected by coal-gangue, such as heavy metals (Mn, Cr, Cd, Ni, Zn, Cu, Pb), As, pH, cation exchange capacity (CEC), sulfur (S) and iron (Fe), were tested...
Coal mining is indispensable due to the widespread use of coal, and gangue is the accumulated solid waste byproduct that persists in mined lands, even after the mines have been abandoned 1.In the ...
In the experiment, coal gangue hollow ball with open pores is used as catalyst for NO reduction by CO in fluidized bed reactor. The preparation process of coal gangue hollow ball with open pores includes the following steps: coal gangue is smashed into 0.1–10 μm; the powders are mixed with water, Y 2 O 3 sintering additive and …
First, this part investigated the effect of mixing only calcined coal gangue on the strength of cementitious materials. The changes in compressive strength of the gelling material at 3, 7, and 28 days with different amounts of calcined coal gangue are shown in Fig. 3.The addition of calcined coal gangue led to a significant decrease in the 3-day compressive …
The crushed coal gangue particles are widely used in solid backfilling. However, the non-uniform compaction and internal re-crushing behavior of crushed coal gangue under bearing-stress have not ...
Liu et al. [26] studied the effect of coal gangue with low kaolinite content on the mechanical properties of cement, and the results showed that for binders with Calcined coal gangue and limestone ...
In summary, this paper studies the stress and strain of coal gangue in the compression process through the confined compression test of coal gangue with different particle sizes in the...
coal‑gangue detection technology in complex structure thick coal seam with multiple gangue. Field tests were conducted in Lilou, Xiaoyu and Tashan Coal Mine.
The beneficial improvement of LC 3 cement on mechanical properties can be ascribed to the synergistic effect of limestone with the OPC and calcined coal gangue forms CO 3-Afm, inhibiting the decomposition of ettringite and reducing porosity.