coal gangue bauxite

Bauxite is the main raw material of ceramic proppants, but with the increasing depletion of bauxite resources, substitutes for bauxite need to be sought. Coal gangue is a solid waste that is rich in SiO 2 and …

The coal gangue accounts for about 10–20% of coal production, and it is one of the largest industrial solid wastes emitted in China [1,2]. It occupies land and pollutes the atmosphere and water ... It makes up for the lack of resources such as bauxite and iron ore. At the same time, the coal industry produces a large amount of wastewater that ...

resource of bauxite. Coal is by far the largest fuel in industrial energy mix, especially in Asia Pacic. In 2018, the coal demand and coal ... short, coal gangue, CFB slag, and CFA are the main by-products of HAC with reckoned production of ~50 million tons per year, with their generation process shown in Fig. 3. ...

The bauxite-calcination-method red mud-coal gangue based cementitious materials mainly form fibrous C-A-S-H gels, needle-like/rod-like AFt in the early hydration period and the hexagonal-prismatic of Ca(OH) 2 crystals are distributed in localized areas of the hardened paste. AFt crystals distribute in the gaps and the pit hole, making the paste ...

The bauxite-calcination-method red mud used in this work was from Shandong alumina refining plant. Coal gangue was obtained from Fangshan District, Beijing. The red mud-coal gangue mixture was thermally activated through a compound activation method [5]. Granulated blast furnace slag (GBFS) was provided by Tangshan …

The raw materials used in this work were coal gangue (Heidaigou Open Cast Coal Mine, Inner Mongolia, China), low-grade raw bauxite (Gongyi, Henan province, China), and α-Al 2 O 3 fine powder (median particle size (d 50) = 1.5 µm, Kaifeng Tenai Co, China).The corresponding chemical compositions are listed in Table 1.Kaolinite, …

The concentration anomalies of Ga and Li in No. 5-2 high-sulfur coal were not caused by the Benxi Formation Bauxite, but by the influence of multiple geological factors.

However, coal gangue is a rejected resource of aluminum and iron, from which aluminum and iron ions can be extracted to expand the applications of gangue. It makes up for the lack of resources such as bauxite and iron ore. At the same time, the coal industry produces a large amount of wastewater that needs to be treated.

Owing to kaolinite in coal gangue, extraction of alumina from coal gangue can replace bauxite as a source of alumina. When coal gangue were used to produce …

Large amounts of by-products, including coal gangue, circulating fluidized bed (CFB) slag, and coal fly ash (CFA), are generated during mining, washing and burning of high alumina coal (HAC). The stockpile of these by-products of HAC will cause the pollution of air, water and soil. Meanwhile, the unbalanced regional distribution of …

This article uses coal gangue and loess as the main raw material (coal gangue:loess = 8:2), calcium carbonate as the pore-forming agent, and carboxymethyl cellulose as the binder. The ceramic membrane was prepared by extrusion molding method and solid particle sintering method. The effects of pore-forming agent content and …

Large amounts of high-alumina coal gangue (HACG) with the main mineral of kaolinite [Al 2 Si 2 O 5 (OH) 4] are generated during the mining and washing of this coal. Meanwhile, the alumina production in China was ~ 73 million tons with bauxite consumption of 160 million tons in 2019, but the China's bauxite reserve is only ~ 1 billion tons [ 15 ].

In this research, the micro-structural characterization of the hydration products of red mud-coal gangue based cementitious materials has been investigated through SEM-EDS, (27)Al MAS NMR and (29)Si MAS NMR techniques, in which the used red mud was derived from the bauxite calcination method. The re …

PDF / ePub. More. Abstract. In the work, a novel mullite refractory was prepared by using coal gangue and low-grade raw bauxite as main raw materials, and …

The coal gangue generated from this area is thereby rich in alumina (Al 2 O 3, 40–50 wt%), which is almost the same as some middle and low-grade bauxite . Alumina mainly extracted from bauxite is widely used in catalysts, adsorbents, ceramics, refractory, metallurgy and many other areas [ 19 ].

A deep investigation on the hydration mechanism of bauxite-calcination-method red mud-coal gangue based cementitious materials was conducted from viewpoints of hydration products and hydration heat analysis. As a main hydration product, the microstructure of C-A-S-H gel was observed using high resolution transmission …

1. Introduction. With the increased global depletion of bauxite reserves and the concurrent growth in the demand for alumina resources, it is important to search for the alternatives to bauxite [1], [2], [3].Coal gangue produced from coal mining and coal processing is one of the largest amounts of industrial solid wastes in China [4], [5].The …

Extracting Al2O3 from coal gangue achieves the high-value utilization of coal gangue and alleviates the shortage of bauxite resources in China, which have good economic and social benefits [13]. The reported methods for extracting Al from coal gangue are primarily divided into alkaline and acid methods [14].

Preparation of microporous mullite refractories with high strength based on low‐grade bauxite and coal gangue - Chen - 2024 - International Journal of Applied …

In this study, low-grade bauxite and coal gangue were used as the main raw materials to prepare microporous mullite refractories with low thermal conductivity and high strength by the in situ decomposition method. The effect of coal gangue content and sintering temperature on the structure and properties of mullite refractories was also ...

The XRD patterns of calcined coal gangue and bauxite are shown in Fig. 1.As shown in Fig. 1 a, the crystalline phases detected in coal gangue are quartz as major phase (SiO 2, hexagonal system, PDF# 850797) and potassium mica as minor one (KAl 3 Si 3 O 11, monoclinic system, PDF# 460741). Fig. 1 b presents that calcined bauxite …

The leaching kinetics of alumina extraction from coal gangue with hydrochloric acid was investigated. The effects of calcination activation temperature and leaching conditions on the alumina extraction efficiency were studied. ... [30,31], low-grade kaolinite [32], aluminum dross [33], red mud [34], and high-silica bauxite [35,36]. …

In this study, low‐grade bauxite and coal gangue were used as the main raw materials to prepare microporous mullite refractories with low thermal conductivity and high strength by the in situ ...

A deep investigation on the hydration mechanism of bauxite-calcination-method red mud-coal gangue based cementitious materials was conducted from viewpoints of hydration products and hydration ...

China's bauxite imports more than 60 million tons, to achieve the industrial production of coal gangue extraction Al 2 O 3, can reduce the import pressure of …

In this study, the co-roasting of high-Fe bauxite with coal gangue for iron and aluminum recycling was explored. The optimum conditions for co-roasting were roasting at 750 °C for 50 min with 40% coal gangue, and 70.55% particles with size <37 µm. Through magnetic separation, iron ore concentrate with 55.09% TFe and a recycling rate of …

Coal gangue is one of the largest mine solid wastes in China, and its discharge and stockpiling have caused resource waste, environmental pollution and other problems. ... Hydration mechanism and leaching behavior of bauxite-calcination-method red mud-coal gangue based cementitious materials[J]. Journal of Hazardous Materials, …

The hydration products of bauxite-calcination-method red mud-coal gangue based cementitious materials (samples O, A and B) have been investigated in our previous work [8]. In order to figure out the hydration mechanism of red mud-coal gangue based cementitious materials, it is necessary to summarize some of the important information …

The red mud was obtained from Shandong province, China; the coal gangue was collected from Shanxi province, China. The red mud particle sizes used in this study ranged from 0.1 to 750 μm; the coal gangue is crushed to a particle size of ≤2 mm, and then ground into fine powder, with 70 wt% particles smaller than 0.038 mm. …

Moreover, the alkali solution is easier to enter the inside of the coal gangue glass body, and OHcan break the surface Al-O, Si-O network [46], the Si element of S-CG is 1.8 times that of Raw-CG ...

Porous mullite ceramic supports for filtration membrane were successfully fabricated via recycling of coal gangue and bauxite at sintering temperatures from 1100 …