Strength of coal particles is an important mechanical property that is of great significance in the prevention of coal and gas outburst. The force-displacement curve for each small particle was obtained by the uniaxial compression of 1200 coal particles of sizes in the range 0.2–7 mm and different degrees of deterioration ranging from low-rank …

Abstract Determination of the coal-strength coefficient in accordance with State Standard GOST 21153.1–75 is clear and simple. No complex equipment is required, and capital expenditures and energy costs are relatively low. This method satisfactorily reproduces the crushing conditions of coal in hammer systems, and the granulometric …

The intact coal strength, i.e., the strength when particle size d → 0, is in the range 10–88.79 MPa, and the coal mass strength, i.e., the strength when d → ∞ is in the range 0.92–8.03 MPa.

The densification parameters for sub-bituminous coal briquette were optimized in this study to obtain 12 maximum drop to fracture (DF), water resistance index (WRI), and cold crushing strength (CCS).

And the actual coal crushing performance was tested. The test results show that the force of the cutting mechanism in the impact mode is lower than that of the nonimpact mode, and the force is ...

CO 2 fracturing enhances gas permeability by creating a complex network of fractures in coal seams. Crushing serves as the foundation of fracture development, …

Coal gangue, as a subgrade filler, is of great significance for the sustainable development of the economy, society, and environment. Particle crushing tests were conducted on coal gangue coarse-grained subgrade filler (CGSF) under uniaxial compression conditions, and the relationships between load and displacement, …

CO 2 fracturing enhances gas permeability by creating a complex network of fractures in coal seams. Crushing serves as the foundation of fracture development, and studying the coal crushing behavior under supercritical CO 2 transient high-pressure fracturing is of great significance to understand fracture evolution and guide precise …

Estimating compressive strength. General rock failure criterion can be reduced to a few parameters dependent on lithology (m) and the uniaxial compressive strength (C 0).Lithology is commonly derived during log analysis, so m may be estimated (Table 1).What is needed still is an initial measure of rock strength provided by C 0. C 0 …

Fundamental research on single-particle breaking and the uniaxial compressive strength (UCS) of carbonaceous mudstone aggregates at different water contents was carried out to investigate the relationship between the single-particle crushing strength and UCS. Based on elasticity theory and the superposition principle, a shape …

It is important to understand the relation between the inert size and coke strength precisely to improve coke strength by the coal crushing. In this paper, the inert size was actually measured ...

Cold crushing strength of the briquettes. Figure 4 shows the cold crushing strength (CCS) for the briquettes. The CCS depicts the ease of breakage or wear during transportation, handling and ...

Firmness is one of the most important physical properties of rock, and indicates the rock's ability to resist damage. It has considerable relevance to mining, blasting, tunneling, construction, and other engineering fields. In this study, the fractal particle-size-distribution theory was used to calculate the surface areas of coal particles …

An analysis reveals that the absorbed energy—synonymous with crushing work—escalates as the impact strength augments, instigating a nearly linear rise in the …

Understanding the mechanical properties of coal is crucial for efficient mining and disaster prevention in coal mines. Coal contains numerous cracks and fissures, resulting in low strength and challenges in preparing standard samples for testing coal fracture toughness. In engineering, indicators such as the hardness coefficient (f value) …

In the case of the 10% coal tar pitch addition, the cold crushing strength of ferro-coke was increased from 18.15% to 76.41%; meanwhile, its hot compression strength during gasification improved ...

The results show that at the moment of gas release, coal particles and gas are ejected at high speed, crushing coal particles into smaller particles. With the increase in gas pressure and gas adsorption …

The main business includes: coal crushing technology and equipment, non-coal crushing technology and equipment, dry environmental protection technology and equipment, intelligent control technology and equipment, etc. ... ESTABLISHED IN 2001 58078 M². OVERALL FLOORAGE 58078.68 square meters 1000 + Project Site 1000 The strength …

The factors affecting the mining efficiency of top coal in fully mechanized caving mainly include coal seam occurrence (coal seam thickness and burial depth, etc.) and coal body strength (fracture density and distribution in coal body and gangue distribution in top coal). When the top coal strength is too high (f > 3) or the crack is not …

Coal agglomerates of 0.015-0.0277m were produced and the weight and crushing strength of the agglomerates were determined. Kerosene (paraffin oil) was …

Methods of assessing coal strength are compared on the basis of a literature review. The Hardgrove grindability index (HGI) is the most expedient.There is a close relation between HGI and the coal quality, as well as the power consumed in grinding. Accordingly, the HGI values of coal samples may be used to optimize the crushing of …

There is a close relation between HGI and the coal quality, as well as the power consumed in grinding. Accordingly, the HGI values of coal samples may be used to optimize the …

the major parameter responsible for coal cake break-age at coke plant, the stability of coal cake was further investigated by measuring the shear strength of the cylindrical coal cake by universal strength testing machine (Fig. 5). 2.4. Bulk Density and Stamping Energy Measurement (Plant Scale) 30 days bulk density measurement trial was carried

By combining these results with the experimental results from the literature, the suitability of the Weibull model to describe the size effects on the breakage strength of rock grains is discussed. To understand why larger grains possess lower strength, a bonded particle model (BPM) is established in YADE to simulate the particle crushing …

The changing rules of dynamic strength, crushing, fractal dimension and damage modes of coal under different stress conditions were analyzed. A total of nine …

sands, the particle crushing strength of granulated coal ash did not depend on the particle size. Moreover, the crushing strength affected the shear characteristics, i.e., as the crushing strength increased, the shear stiffness became higher and the shrinkage of the volumetric strain became smaller.Therefore, crushing strength can be a

6. coal of adequate crushing strength. 2.3 Describe depillaring method with stowing and caving. DEPILLARING WITH STOWING : Depillaring with stowing is a method of pillar extraction in which the goaf is completely packed with incombustible material and in generally practiced where it is

strength variations of pre-tensioned rocks, with Zhao33focusing on the fractal traits of coal-bearing seam crack extensions under similar conditions. Li 34 entailed introducing radial …

The cutting and crushing of coal and rock containing gangue is the result of the coupling effect of multiple factors. The geometric parameters of the working mechanism, the kinematic parameters of ...

The highest cold crushing strength of 4 MPa was obtained for briquettes produced from 97% coal fines and 3% torrefied biomass. The highest drop to fracture (54 times/2 m) and impact resistance index (1350) were obtained for the sample produced from 97% coal and 3% torrefied biomass.