The Status and Analysis of the Equipment for Fine Mineral Particle Classification in Coal Wash Plants

2012 ◽  
Vol 625 ◽  
pp. 202-205 ◽  
Author(s):  
Jiao Ma ◽  
Shan Hong Zou ◽  
Xiang Zhen Wang ◽  
Bin Hui ◽  
Xu Dong Liu ◽  
...  
Keyword(s):  
Coal Mining ◽  
Fine Particle ◽  
Fine Particles ◽  
Water System ◽  
Gravity Separation ◽  
Mineral Particle ◽  
Coal Preparation ◽  
Fine Coal ◽  
The Status ◽  
Particle Classification

This article is about the methods and equipment being used in the first step of slime water system, which is called fine particle classification. With the development of automation in coal mining and preparation, fine particles in the raw coal increases substantially. The fine coal preparation is mainly completed in water, which makes the slime water system face to a heavier load. Accurate classification is necessary to large-grained gravity separation and small-grained flotation.

Research and Application on Technology of Flood-Storage and Flood-Detention of Coal Mining Subsidence Area of Suzhou Coal Mine

2014 ◽  
Vol 641-642 ◽  
pp. 80-83
Author(s):  
Jia Zhong Zheng ◽  
Mei Zhu ◽  
Zheng Long Wang
Keyword(s):  
Coal Mining ◽  
Dynamic Change ◽  
Storage Conditions ◽  
Flood Routing ◽  
Mining Subsidence ◽  
Subsidence Area ◽  
The Status ◽  
Suzhou City ◽  
Change Trend ◽  
Coal Mining Subsidence

The artical is based on the investigation of the basis of the status quo of Zhuxianzhuang and Luling coal mining subsidence area in Anhui province Suzhou city(hereinafter referred to as the "Zhu Lu subsidence area"), a preliminary analysis of the dynamic change trend of detention space in Zhu Lu subsidence area, and based on the hysteresis storage conditions of subsidence area, use the flood routing model to simulate the hysteresis effect of storage at different subsidence scenarios of different frequency flood. Finally, using the experience type channel evolution model and peak delay routing model further revealed storage effect on flood process of Zhu Lu subsidence area.

Application of Ceramic Membrane Technology in Tungsten Fine Particle Concentration Process

2014 ◽  
Vol 692 ◽  
pp. 191-199
Author(s):  
Wan Fu Huang ◽  
Xiao Feng Wang ◽  
Xin Dong Li ◽  
Si Ming Yan
Keyword(s):  
Fine Particle ◽  
Particle Concentration ◽  
Fine Particles ◽  
Ceramic Membrane ◽  
Membrane Technology ◽  
Factors Affecting ◽  
Membrane Flux ◽  
Concentration Test ◽  
Optimal Effect ◽  
Membrane Concentration

This study used ceramic membrane technology to concentrate tungsten fine particles for its inefficient recycling issue. Factors affecting the membrane concentration test were discussed, and the results show that: under the feed flow of 7000 mL/min, concentration time of 3 hours, and concentration liquid flow of 500 mL/min, it is the optimal effect of ceramic membrane concentration tungsten fine particle, which the interception rate reaches more than 99%, the membrane permeation flux can be nearly reach 470mL/(min×1099cm2) above, and concentrate concentration can be basically stable at around 29% . Ceramic membrane flux recovery rate can be as high as 93% by 7 minutes backwashing firstly and then 2 minutes forward cleaning.

scholarly journals Study of pressurised metered dose inhalers for the purpose of standardization of quality attributes characterizing uniformity of dosing

2021 ◽  
pp. 11-23
Author(s):  
Elena Bezuglaya ◽  
Nikolay Lyapunov ◽  
Vladimir Bovtenko ◽  
Igor Zinchenko ◽  
Yurij Stolper
Keyword(s):  
Particle Size ◽  
Fine Particle ◽  
Fine Particles ◽  
Average Dose ◽  
Metered Dose Inhalers ◽  
Fine Particle Dose ◽  
Particle Dose ◽  
Metered Dose ◽  
Delivered Dose

Aim. The purpose was to provide the rationale of test in regard to uniformity of fine particles dose for pressurised metered dose inhalers (pMDIs). Materials and methods. The pMDIs containing suspensions of salbutamol sulfate (SS) or solutions of beclometasone dipropionate (BD) were studied by laser diffraction and high performance liquid chromatography (HPLC). The particle size distribution of SS, the average dose mass and uniformity of dose mass, the average delivered dose and the uniformity of delivered dose, the average fine particles dose and uniformity of fine particles dose were determined. Apparatus A was used for assessment of fine particles dose. Results. The two analytical procedures for the quantitative determination of SS and BD by HPLC were validated in the ranges with low concentrations of these substances. The 5 medicinal products in pMDI dosage form were studied: 3 preparations were with SS and 2 ones contained BD. It was shown that three products with SS were very similar in regard to particle size distribution in containers and the average values of delivered dose were almost the same, but these products were different in the average dose mass and fine particle dose. According to the research results, the expediency of determining the average dose mass and the tests concerning uniformity of dosing of preparations by dose mass and by fine particle dose was substantiated. It was shown that in the case of pMDI the dosing of solutions of BD was more uniform compared to suspensions of SS. The approaches of leading and other pharmacopoeias concerning uniformity of dosing for pMDIs were critically discussed. The expediency of determination of uniformity of fine particle dose at the stage of pharmaceutical development was substantiated, as the therapeutic effect depends on fine particle dose. Issues concerning standardization pMDIs in regard to uniformity of fine particle dose were discussed. Conclusions. The expediency of standardization and quality control of pMDIs in regard to such attributes as the average dose mass, which characterizes the volume of the metering chamber of the valve as well as the uniformity of the dose mass and the uniformity of fine particle dose, which assure the therapeutic effect of each dose of the product was substantiated

scholarly journals Fault Diagnosis of Coal Mining Machinery Based on State Parameters

2020 ◽  
Author(s):  
Dong Song
Keyword(s):  
Fault Diagnosis ◽  
Coal Mining ◽  
Fault Type ◽  
Fault Parameters ◽  
Underground Coal Mines ◽  
Mining Machinery ◽  
The Status ◽  
New Perspective ◽  
Judgment Condition ◽  
Cutting Unit

The reliable operation of coal mining machinery acts as an important guarantee for safe productions in underground coal mines. The status monitoring and fault diagnosis of traditional coal mining machinery mainly rely on threshold judgments. However, a single judgment condition and a long fault propagation chain can be found in the method of threshold judgments, which make it difficult to accurately seek the fault type. By using the data analysis of state parameters for coal mining machinery, fault parameters and propagation paths can be analyzed effectively. This paper takes the cutting unit of a certain type of bolter miners as an example, a static and dynamic numerical analysis method of the cutting unit of bolter miners are established by virtue of FTA-Petri net models and BP-Firefly neural networks, which can provide a new perspective for fault diagnosis of coal mining machinery.

scholarly journals A Feasibility Study Evaluating the Efficiency of Fine Coal Washing Using Gravity Separation Methods

2019 ◽  
Vol 2 (4) ◽  
pp. 497
Author(s):  
Agnes Modiga ◽  
Ndabenhle Sosibo ◽  
Nirdesh Singh ◽  
Getrude Marape
Keyword(s):  
South Africa ◽  
Calorific Value ◽  
Ash Content ◽  
Gravity Separation ◽  
Export Market ◽  
Heavy Liquid ◽  
High Mass ◽  
Fine Coal ◽  
Classifier Performance ◽  
Uranium Industry

Coal mining and washing activities in South Africa often lead to the generation of fine and ultra-fine coal which is in most cases discarded due to high handling and transportation costs. Studies conducted revealed that a large quantity of these fines have market acceptable calorific values and lower ash contents. In order to reduce fines discarded, processes have been developed to re-mine and process the fine coal discards with the aim of improving the calorific value, adding them to coarse washed coal to increase the yield as well as pelletizing the fines so as to meet the market specifications in terms of size. The goal of this study was to evaluate the efficiency of fine coal washing using gravity separation methods and comparing the products thereof to the market specifications with regards to the calorific value and the ash content. Coal fines from the No.4 lower seam of the Witbank coalfield in South Africa resulting from a dry coal sorting plant were subjected to a double-stage spiral test work, heavy liquid separation and reflux classifier test work respectively. The reflux classifier achieved products with low ash content and an increased calorific value, at high mass yields. At higher fluidization water flowrate, the reflux classifier performance was superior to that of the spirals with products of lower ash content and higher calorific value. At low cut point densities, heavy liquid separation yielded the cleanest products with very low ash content but at much lower mass yields. As the density increased, the mass yields increased with the ash content while the calorific value decreased. Most of the products from the different processes met most of the local industries’ specifications but none of them met the export market as well as the gold and uranium industry specifications due to the high ash content.

scholarly journals Structure and Strength of Artificial Soils Containing Monomineral Clay Fractions

Materials ◽  
2021 ◽  
Vol 14 (16) ◽  
pp. 4688
Author(s):  
Grzegorz Jozefaciuk ◽  
Kamil Skic ◽  
Agnieszka Adamczuk ◽  
Patrycja Boguta ◽  
Krzysztof Lamorski
Keyword(s):  
Fine Particles ◽  
Structural Parameters ◽  
Fractal Dimensions ◽  
Soil Strength ◽  
Uniaxial Compression Test ◽  
Mineral Particle ◽  
Type Curve ◽  
Surface Fractal ◽  
First Time

Structure and strength are responsible for soil physical properties. This paper determines in a uniaxial compression test the strength of artificial soils containing different proportions of various clay-size minerals (cementing agents) and silt-size feldspar/quartz (skeletal particles). A novel empirical model relating the maximum stress and the Young’s modulus to the mineral content basing on the Langmuir-type curve was proposed. By using mercury intrusion porosimetry (MIP), bulk density (BD), and scanning electron microscopy (SEM), structural parameters influencing the strength of the soils were estimated and related to mechanical parameters. Size and shape of particles are considered as primary factors responsible for soil strength. In our experiments, the soil strength depended primarily on the location of fine particles in respect to silt grains and then, on a mineral particle size. The surface fractal dimension of mineral particles played a role of a shape parameter governing soil strength. Soils containing minerals of higher surface fractal dimensions (rougher surfaces) were more mechanically resistant. The two latter findings appear to be recognized herein for the first time.

scholarly journals Atmospheric oxidation capacity in Chinese megacities during photochemical polluted season: radical budget and secondary pollutants formation

2018 ◽  
Author(s):  
Zhaofeng Tan ◽  
Keding Lu ◽  
Meiqing Jiang ◽  
Rong Su ◽  
Hongli Wang ◽  
...  
Keyword(s):  
Fine Particle ◽  
Fine Particles ◽  
Nox Reduction ◽  
Ozone Production ◽  
Atmospheric Oxidation ◽  
Ozone Pollution ◽  
Oxidation Capacity ◽  
Radical Chemistry ◽  
Budget Analysis ◽  
Secondary Pollutants

Abstract. Atmospheric oxidation capacity is the core of converting fresh-emitted substances to secondary pollutants. In this study, we present the in-situ measurements at four Chinese megacities (Beijing, Shanghai, Guangzhou, and Chongqing) in China during photochemical polluted seasons. The atmospheric oxidation capacity is evaluated using an observational-based model with the input of radical chemistry precursor measurements. The radical budget analysis illustrates the importance of HONO and HCHO photolysis, which contribute nearly half of the total radical primary sources. The radical propagation is efficient due to abundant of NO in the urban environments. Hence, the production rate of secondary pollutants, i.e. ozone and fine particle precursors (H2SO4, HNO3, and ELVOCs) is fast resulting in secondary air pollution. The ozone budget demonstrates that strong ozone production occurs in the urban area which results in fast ozone concentration increase locally and further transported to downwind areas. On the other hand, the O3-NOx-VOC sensitivity tests show that ozone production is VOC-limited, among which alkenes and aromatics should be first mitigated for ozone pollution control in the presented four megacities. However, NOx emission control will lead to more server ozone pollution due to the drawback-effect of NOx reduction. For fine particle pollution, the role of HNO3−NO3− partitioning system is investigated with a thermal dynamic model (ISORROPIA2) due to the importance of particulate nitrate during photochemical polluted seasons. The strong nitrate acid production converts efficiently to nitrate particles due to high RH and ammonium-rich conditions during photochemical polluted seasons. This study highlights the efficient radical chemistry maintains the atmospheric oxidation capacity in Chinese megacities, which results in secondary pollutions characterized by ozone and fine particles.

Acoustic waste water clarification practices

2021 ◽  
pp. 32-37
Author(s):  
S. A. Bakharev
Keyword(s):  
Suspended Solids ◽  
Fine Particles ◽  
Far East ◽  
Water System ◽  
Acoustic Method ◽  
Environmental Safety ◽  
Environmental Indicators ◽  
Asia Pacific ◽  
High Productivity ◽  
Acoustic Impact

The article covers the problems of reagent-free clarification of circulating and waste waters of enterprises with their production sites located in valleys of spawning rivers in the environmentally-sensitive northern territories. It is shown that horizontal sumps, widely used at mining enterprises due to their low construction and operation costs, fail to ensure the production and environmental indicators required in the current conditions. The article analyses the results of 20 years of application in the Russian Federation and the countries of the Asia-Pacific region of the complex acoustic method (CAM), based on the mechanisms of coagulation of fine particles, forced sedimentation of initial and coagulated particles, as well as sludge thickening and dewatering. The advantages and limitations are shown for the CAM method, developed by the author of the article and based on the principles of: complexity, with the use of the laws of linear and nonlinear acoustics; acoustic impact on the water system for the purpose of acoustic degassing of water; acoustic coagulation of fine suspended solids (and subsequent gravity sedimentation of the newly formed aggregates); acoustic (forced) sedimentation of the original and previously acoustically coagulated suspended solids; acoustic thickening of sludge in sumps and acoustic dewater ing of sludge at depositing sites with drainage systems; the cascade (boundary) nature of acoustic impacts on the water system in the main water catchers, sumps, etc. The specific behavior of processes under a complex acoustic impact ensures their high productivity and low power consumption values (unattainable by any other methods) and the required environmental safety in the special conditions of the Far North and the Far East.

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