Summary and Conclusions. Flotation kinetic behavior of coal can be described by a first-order flotation kinetic model with a sine function (in the range of 0 to π/2) distribution of flotabilities in the flotable particles. The ultimate recovery and flotation rate constant obtained by fitting experimental results with this kinetic model ...
A method for the separation of carbonaceous material from inorganic matter comprising the steps of mechanically working a feed stream; applying a separation …
namely reverse flotation−grinding−re-separation,to obtain the clean coal product with a yield of 25% and an ash content of 13.96%. It is worth noting that the above re-separation processes of coal flotationtailing all include a grinding stage. The carbon component in the coal flotationtailings is closely
Clean coal with 67.2% combustible matter recovery and 10.5% ash content was obtained by gaseous dodecane pretreatment flotation method. Coal water slurry with 60% concentration was prepared using ...
Coal flotation is a complex process involving several phases (particles, oil droplets and air bubbles). These phases simultaneously interact with each other and with other species such as the molecules of a promoting reagent and dissolved ions in water. The physical and chemical interactions determine the outcome of the flotation process.
The mass production of flotation tailings has become a serious risk to the environment. Re-concentration of tailings is one of the best ways to solve this problem, which requires a better understanding of flotation tailings. In the present work, flotation kinetics, timed-release flotation, X-ray diffraction (XRD), Fourier transform infrared spectroscopy …
As the reserves of high-quality coal resources in China are decreasing, it is imperative to improve the processing and comprehensive utilization of low-rank coal. In this study, NaNO2 was used for the …
A froth image dataset from the coal flotation site was divided into seven interval classes based on concentrate ash content, and data augmentation was used for this dataset. Then, several state-of-the-art convolutional neural networks (AlexNet, VGG_16, VGG_19, ResNet_18, ResNet_34, ResNet_50, ResNet_101) are trained to classifying the …
An important element of increasing the carbonaceous yield from coal deposits is to reduce the amount of carbonaceous material in the tailings stream of coal extraction plants. …
In coal flotation, coal particles collide with and then attach to air bubbles. The bubble–particle aggregates rise to the froth phase and then enter the concentrate. ... X-ray diffraction analysis showed that this coal sample contained 82.9% unidentified/amorphous mineral, 5% quartz, 3.9% kaolinite, 2.8% muscovite, 3.4% mixed …
In this study, a short-chain cationic amine, n-octylamine, was added into diesel in 1:4 ratio for enhancing oxidized coal flotation. X-ray photoelectron spectroscopy (XPS) was used to identify the ...
The combined use of Fe 2+ and oleic acid enhanced low rank coal flotation. Fe 2+ mainly exists in the form of Fe (OH) + in the pulp at natural pH. Fe (OH) + bounded with the hydroxyl group on the low rank coal surface. An adsorption model of oleic acid and Fe (OH) + on coal surface was presented.
Despite there are several investigations indicated the application of ultrasonic waves during the coal flotation processes [17, 18, [23][24][25], there is a considerable lack of study on ...
The mass production of flotation tailings has become a serious risk to the environment. Re-concentration of tailings is one of the best ways to solve this problem, which requires a better understanding of flotation tailings. In the present work, flotation kinetics, timed-release flotation, X-ray dif …
Furthermore, the hydrophobic groups of the benzene ring in 4-dodecyl phenol (4-DDP) could adsorb onto the coal surfaces through π-π bonds, enhancing the surface hydrophobicity of long-flame coal. Moreover, the flotation performance of long-flame coal was significantly improved using the emulsified mixture of kerosene and 4 …
2.2. Flotation tests. Coal flotation was conducted in a 1.5 dm 3 JK batch flotation cell using de-ionised water. For each test, 100 g dry coal sample was added into 0.7 dm 3 water and stirred for 3 min at an agitation speed of 1200 rpm to achieve the sufficient dispersion of coal particles. Then the slurry was topped up to 1.5 dm 3 by …
A mixture of low-ash coal and gangue particles was used to investigate the effects of sodium oleate (NaOL), kerosene, and sodium hexametaphosphate (SHMP) on low-rank coal flotation. X-ray ...
Ash content is an important index to evaluate product quality and adjust equipment parameters in coal flotation. Coal ash determination standards [[4], [5], [6]] require complex procedures, including sampling, drying, sample preparation, burning, weighting and calculation. This complex process is time-consuming and labor-intensive.
Therefore, high-ash coal has earned considerable interest in the fields of flotation and gasification. On one hand, it has been used to recover clean coal by flotation in industrial practice [2][3 ...
Efficient flotation of low-rank coal is of great significance for the development of green and low-carbon cycles. Temperature is a crucial parameter of flotation, but the mechanism of its effect on flotation lacks understanding. In this paper, the mechanism was studied by kinetic flotation, scanning electron microscopy (SEM), Fourier transform infrared spectroscopy, …
According to the advantages of existing technologies, a green and sustainable flotation process for low-rank/oxidized coal combining pretreatment …
phases in the coal flotation pulp, their interactions with each other and how these interactions affect the flotation process are discussed. 2. Disperse phases in coal flotation There are three dispersed phases that constitute flotation pulp: coal particles, oil droplets and air bubbles. These phases interact in water as the medium
The present review paper summarizes the up-to-date research advancements made in the use of mixed reagent systems to improve the separation efficiency of coal …
India can increase the domestic production of coking coal. fine grinding to improve liberation, advanced flotation to remove ash, and advanced dewatering to remove …
A large number of surfactants together with auxiliary additives are used in froth flotation. Herein, we discuss the important surfactants, focusing on the mechanism by which they act in coal flotation processes. Coal and …
A mixture of low-ash coal and gangue particles was used to investigate the effects of sodium oleate (NaOL), kerosene, and sodium hexametaphosphate (SHMP) on low-rank coal flotation. X-ray ...
The results showed that when the dosage of NaNO 2 was 2000 g/t and the pretreatment time was 5 min, the flotation effect was the best, the ash contents of concentrate ash and tailings and the combustible recovery were 17.15, 37.12, and 42.23%, respectively; the combustible recovery increased by 12%.
In addition, we discussed a new kinetic model-fitting approach for. coal flotation. Results show that the main gangue mineral in the fine coal is kaolin-. ite. The middle density fraction of 1.40 ...
The interaction mechanism of the microemulsion collector on enhancing the low-rank coal flotation was elucidated through the Zeta potential and contact angle measurements, the Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy analysis. The microemulsion collector exhibited superior dispersibility, …
Clean coal with 67.2% combustible matter recovery and 10.5% ash content was obtained by gaseous dodecane pretreatment flotation method. Coal water slurry with 60% concentration was prepared using ...