2013 0(TTPT)

Back to table of content

   Short abstract

 

Pages:

171 - 180

Language:

RU

Ref.:

8


Click to get extended abstract


Download paper: [RU]

2013_0(TTPT)_20.pdf

 

 

INVESTIGATIONS OF ELECTRIC PROPERTIES OF COAL-WATER SUSPENSIONS

doi:10.23877/MS.TS.13.020

Pinchuk V.A., Dolzhanskiy A.M.

National Metallurgical Academy of Ukraine (NMetAU), Dnepropetrovsk, Ukraine


Citation:

Pinchuk, V.A. and Dolzhanskiy, A.M., (2013) Investigations of electric properties of coal-water suspensions, Modern Science: Researches, Ideas, Results, Technologies, Iss. #0(TTPT), PP. 171 - 180. doi: 10.23877/MS.TS.13.020.


Keywords:

coal-water slurry; electric current; polarization; double electric layer; the electrical resistivity


Abstracts:

Currently, due to the increasing use of electromagnetic interference for preparation and further processing of fuels the study of their electrical properties is of great scientific and practical interest. One of the most important indicators of the electrical properties of coal-water slurry is the electrical conductivity and its inverse value - electrical resistance. Magnitude of electric resistance of the fuel and its value determines the optimal parameters of the electromagnetic pre-treatment and processing of the fuel depending on a number of factors.
Coal-water slurry refer to disperse systems. It is known that such systems hold not only an electronic ("hole") conductivity, but also the ionic. Charge transfer with the dispersed phase and the displacement currents also occur. This shows a very complex mechanism of coal-water slurries conductivity formation, and the necessity of experimental research to determine the regularities of electromagnetic processes in coal-water slurry and its electrical properties. In order to determine the electrical properties of coal-water slurries prepared from coals of different stages of metamorphism, the research facility was developed. Research has shown that a coal-water slurry is characterized by the initial electrical potential of the order of 12 ... 200 mV, depending on the type of coal from which the fuel is prepared. It testifies spontaneous polarization of coal-water slurry.
In addition, the study results indicate the presence of a coal-water slurry polarization phenomena associated with mobile charge carriers (electrons and ions), and the development of concentration polarization process over time. Found that the electrical resistivity of coal-water slurry varies from 0.4 to 2.3 Ω x m depending on the type of the original coal in the fuel and the voltage. The large amount of water phase in the water-coal slurry leads to a significant reduction in slurry fuel resistivity as compared to coal. Furthermore, mineral impurities in the original coal affect the value of resistivity of coal-water slurries. When increasing the voltage up to certain values the rise of the fuel temperature was observed. At voltages of 120-140 coal-water slurry boiling occurred. The practical application of the results of research of the electrical properties of coal-water slurries can be directly linked to the development of an electromagnetic fuel processing technology to improve the efficiency and adaptability of its use.


References:

  1. Delyagin G.N. Vodnye dispersionnye sistemy na osnove burykh ugley kak energeticheskoe i tekhnologicheskoe toplivo / G.N. Delyagin, A.P. Petrakov, G.S. Golovin, E.G. Gorlov // Rossiyskiy khimicheskiy zhurnal. - 1997. - № 6. - P. 72 - 77.

  2. Пинчук В.А., Губинский М.В. Потапов Б.Б. Использование водоугольного топлива и продуктов его переработки в энергетике и металлургии // Металургійна теплотехніка: Збірник наукових праць Національної металургійної академії України. - Дніпропетровськ: "Нова ідеологія". -2009.- Выпуск 1(16).с. 144-149.

  3. Chemistry and processing of coal / V.G. Lipovich, G.A. Kalabin, I.V. Kalechits etc. - M.: Himiya, 1988. - 336 p.

  4. Agroskin A.A. Physical properties of coal. - M.: Metallurgizdat, 1961. - 308 p.

  5. Beloselsky B.S., Novitsky N.V. The electrical properties of watercoal suspensions / Teploenergetika. - 1986. - № 3. - P. 42-44.

  6. Dukhin SS Electrical conductivity and electrokinetic properties of dispersed systems. - K.: Naukova Dumka, 1975. - 248 p.

  7. Dukhin S.S., Shilov V.N. Dielectric phenomena and the double layer in disperse systems and polyelectrolytes. - K.: Naukova Dumka, 1975. - 246 p.

  8. Great Encyclopedia of oil and gas [electronic resource - the data access mode http://ngpedia.ru/].

 

 
     

© SPIC "Kappa", LLC 2009-2016