摘要:

The adsorption of phenol, p-nitrophenol, the nonionic surfactant Triton X-100 (a commercial mixture of octylphenol poly ethoxylates) and the cationic surfactant dodecyltrimethylammonium bromide (DTAB) from aqueous solution on coal fines from a coal washing plant has been studied. Adsorbate solution concentrations range from 0-8 × 10-4m. For the cationic and nonionic surfactants both adsorption isotherms and electrokinetic isotherms were determined. The adsorption of phenol, but not of Triton X-100 and DTAB, is found to increase with time for periods up to 300 h. For short contact times (< 30 h), the amount of Triton X-100 adsorbed is about three times higher than the amount of phenol adsorbed at the same solution concentration. The electrokinetic data show that the zeta potential of the coal is not affected by the adsorption of Triton X-100. On the other hand, adsorption of the cationic surfactant strongly influences the zeta potential. For negatively charged coal, i.e., at higher solution pH (iep of the coal used in 5.3), the adsorption of cationic surfactant leads to charge reversal at a typical free surfactant concentration often well below 10-4molal

ISSN:0734-9343    

DOI:10.1080/07349348508945543

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor

摘要:

Persistent crude petroleum-water emulsions are produced in the recovery and extraction of heavier oils, for example, in the hot water processing of surface mined oil sands and during in-situ methods such as steam- or water-flooding. Over the past few years, much attention has been directed to the oil agglomeration method as a means of recovering and upgrading fine coal in water suspensions. The work reported here concerns the use of crude petroleum from produced emulsions in the coal agglomeration process. Two problems are adddressed in this way. Not only is oil recovered and emulsions broken in the case of the produced emulsions, but the coal is also benificiated through the rejection of water and inorganic impurities because of the selectivity of the agglomeration technique.

ISSN:0734-9343    

DOI:10.1080/07349348508945544

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor

摘要:

Indian coking resources are of inferior quality and have difficult cleaning characteristics. The oil-agglomeration process has the potential to provide a technological break-through for effective beneficiation of such coals. In the present paper the results of an experimental study of the application of oil agglomeration process to thickener underflow from two Indian coal washeries with respect to the yield, grade and size of the agglomerated product have been reported

ISSN:0734-9343    

DOI:10.1080/07349348508945545

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor

摘要:

Agglomeration of coals in a pipeline, using bridging liquids comprised mainly of bitumen, heavy oils and some inexpensive additives, has been investigated. Very encouraging results were obtained for low rank thermal coals. The potential of the pipeline agglomeration method for simultaneous beneficiation and hydraulic transportation of coal agglomerates is discussed in the context of immense Alberta reserves of subbituminous coals and low quality oils

ISSN:0734-9343    

DOI:10.1080/07349348508945546

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor

摘要:

Flotation of subbituminous coal has been investigated with special emphasis placed on the floatability of various petrogiaphic constituents. A nonpolar reagent such as kerosene, and the aliphatic and aromatic heteiopolar agents containing different polar groups (-OH, -COOH, -SO3H) have been used in the flotation experiments. The examined coal docs not float without flotation reagents; the use of kersene only was not enough to induce its floatability eithei. The extent to which the tested coal displayed some floatability depended on the kind of heteropolar reagent added. Microscopic examination has revealed that the flotation of petrographic constituents follows the order: inertinitc > vitrinite > exinite. Based on these results, the effect of the coal structure and its petrographic composition on floatability are discussed

ISSN:0734-9343    

DOI:10.1080/07349348508945547

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor

摘要:

Conventional single-feed coal flotation circuits do not efficiently recover coarse particles. Evidence is presented here that this loss of coarse coal is due to an inability to float coarse middlings material. Both flotation yield and selectivity are improved by replacing single feed flotation with split feed flotation incorporating the separate flotation of coarse and fine particles. While optimum yields from the coarse coal circuits are obtained at approximately the same values of aeration rate and impeller speed as for fine coal, coarse particles are much more sensitive to changes in these variables than fine particles. Froth mobility and froth structure are shown to be factors which limit the recovery of coarse coal. Mobile froths and close vanning are required for optimum coarse coal yields

ISSN:0734-9343    

DOI:10.1080/07349348508945548

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor

摘要:

The historical development of Reichert spirals is breifly reviewed prior to describing models developed specifically for the treatment of coal fines. Results obtained from laboratory tests and field trials of pre-production prototypes are presented. Comparisons are provided both between different tests and between test results and the ideal performance defined by washability data using a graphical technique.

ISSN:0734-9343    

DOI:10.1080/07349348508945549

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor

摘要:

Using a microcomputer a set of computer programs has been systematically developed to simulate distribution curves, calculate the performance characteristics of coal cleaning devices, display the distribution curve shapes on graphic screen or plotter and perform a reliability analysis of the simulated partition curves.

ISSN:0734-9343    

DOI:10.1080/07349348508945550

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor

摘要:

A new method of dewatering coal sludges called “agglomeration of flocculated fines”, is described in this paper. The advantages of the method, both in laboratory studies and for an industrial dehydratoi device are presented

ISSN:0734-9343    

DOI:10.1080/07349348508945551

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor

ISSN:0734-9343    

DOI:10.1080/07349348508945552

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor