摘要:

Among dense medium cyclone operating variables, the medium split ratio is identified as the fundamental operating variable. It is most directly related to dense medium cyclone performance; other operating variables influence the dense medium cyclone performance by changing the medium split ratio. At medium split ratios below one, the separation efficiency deteriorates drastically due to the short-circuiting of the feed. Increasing the medium split ratio improves the separation efficiency. At medium split ratios above 4.0, the improvement in dense medium cyclone performance is insignificant, while the adverse effects of plugging and roping become more pronounced. The cutpoint shift also increases with the medium split ratio. It is recommended that the medium split ratio be close to the overflow to underflow product ratio.

ISSN:0734-9343    

DOI:10.1080/07349349508905239

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

摘要:

The effect of medium composition on dense medium cyclone performance is investigated. It is found that a change in composition affects medium stability and rheology, and may lead to different responses in separation efficiency and cutpoint shift. The final result depends on whether the medium stability or rheology is the dominant factor, and also on the feed particle size.

ISSN:0734-9343    

DOI:10.1080/07349349508905240

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

摘要:

The selective adhesion of hydrophobicMycobacterium phleito coal particles is responsible for flocculation of fine coal from its associated ash forming minerals. The driving force for the differential adhesion is the hydrophobic interactions between the surface of the organism through its constituents such as fatty acids and coal particles. The effect ofMycobacterium phleion surface hydrophobicity, surface charge and mechanism of adhesion on coal and associated minerals are controlled by several factors including hydrophobicity and surface and solution chemistry of the system. Adhesion measurements indicate that maximum adhesion occurs below the iso-electric point (IEP) of the coal particles. While massive adhesion ofMycobacterium phleiis observed on coal, only negligible amount ofMycobacterium phleiattached to pyrite and quartz.

ISSN:0734-9343    

DOI:10.1080/07349349508905241

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

摘要:

Unlike bituminous coals which oxidize upon heat treatment, lower rank coals such as lignites have been found to exhibit improved hydrophobicity on heating. Microflotation tests, zeta potential and infrared measurements have been carried out to understand the flotation behavior of four different lower-rank coals of varying ash and moisture contents. While Yenikoy and Saray coals exhibited improved floatability, Alpagut and Soma coals showed either no improvement or adverse effect upon thermal treatment. The zeta potential values of heat treated samples showed drastic changes compared to the original sample. Interaction of anionic and cationic surfactants with the original and heat treated coals was tested to find out their effect on flotation. A quantitative approach was adapted to correlate the flotation response and the quantity of hydrophobic and hydrophilic groups in coal as determined by infrared measurements. It is shown that the amount of hydrophobic and hydrophilic groups in coal dictates whether a particular coal is conductive to thermal treatment prior to flotation.

ISSN:0734-9343    

DOI:10.1080/07349349508905242

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

摘要:

A fractional factorial design was carried out to determine the relative effects of various design and operating parameters on the performance of a 46 mm diameter Air-Sparged Hydrocyclone (ASH) in treating a sample of fines from a South African (Witbank) Colliery. The effect of (feed) pulp density was also investigated.

ISSN:0734-9343    

DOI:10.1080/07349349508905243

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

摘要:

The choice of preparation technology depends on different factors, resulting in different preparation costs. In order to determine the dependence of the preparation costs upon the complexity of cleaning technology, preparation plants are classified by complexity of preparation (technological models). In Poland, preparation plants can be classified into four types. For two chosen preparation plants, which are representatives of different technological models, the costs of cleaning different coal sizes are presented. The calculations for the analyzed variants were carried out based on discounted costs in order to unify the method of calculation. The principles, methodology and the results of the calculations are the subject of this paper.

ISSN:0734-9343    

DOI:10.1080/07349349508905244

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

ISSN:0734-9343    

DOI:10.1080/07349349508905245

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor