Wyniki wyszukiwania - BazTech

1

Analysis of the combustion process of coal slurry pellets in a circulating fluidized bed

Richter D., Kijo-Kleczkowska A., Kosowska-Golachowska M., Wolski K.

Rynek Energii

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2017

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Nr 4

91--96

EN

The paper presents the results of experimental studies constituting a comparative analysis of the combustion of coal slurry, brown coal, hard coal and biomass in the form of pellets. The study was conducted using a test stand with a circulating fluidized bed (CFB) with a capacity of 12 kW. The analysis included, among other parameters, the total combustion time, the maximum temperature on the surface of the fuel, the ignition time, the time of volatiles combustion and the time of the burning of char. The general conclusion based on experimental studies is that coal slurry pellets, due to its characteristics and behaviour during the combustion process in a circulating fluidized bed, can be a valuable energy source.

PL

W artykule przedstawiono wyniki badań eksperymentalnych dotyczących analizy porównawczej spalania peletów z mułu węglowego, węgla brunatnego, węgla kamiennego oraz biomasy. Badania prowadzono na stanowisku badawczym z cyrkulacyjną warstwą fluidalną Analiza dotyczyła całkowitego czasu spalania, maksymalnej temperatury na powierzchni paliwa, czasu zapłonu i spalania części lotnych oraz czasu spalania karbonizatu. Stwierdzono, iż pelety z mułów węglowych mogą być wartościowym źródłem energii dla kotłów z cyrkulacyjną warstwą fluidalną.

2

Activation of oxidized surface of anthracite waste coal by attrition

Sokolovic J. M., Stanojlovic R. D., Markovic Z. S.

Physicochemical Problems of Mineral Processing

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2012

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Vol. 48, iss. 1

5-18

EN

In this paper the activation of oxidized surface of anthracite waste coal was investigated. Coal weathering leads to physical and chemical changes on the coal surfaces and a reduction of its hydrophobicity and floatability. The changes and the presence of oxygen functional groups in the structure and surfaces coal was confirmed by the FTIR study on the raw and waste coal. The groups have remarkable impacts on surface charge and thus flotation kinetics. The floatability of oxidized coal may be improved by the creation of fresh, unoxidized surfaces on coal by attrition at high solid concentration prior to introducing coal to the froth flotation process. This paper presents the results of the effects of attrition on the floatability of the oxidized surface of waste coal, coal pyrite and alumino-silicate minerals through electrokinetics and microflotation experiments. The results show that the attrition, in the viscous pulp with the solid content of 50%, lead to the mechanical cleaning of oxidized surface and activation of the surface of coal particles, which agrees with the change of zeta potential and increasing floatability of coal by 10%. Obviously that the mechanical scrubbing may be able to restore the natural floatability of superficially oxidized coal by removing the thin oxidation layer from the coal surface. The results show that attrition time is an important parameter from the point of view of activating the oxidized coal surface, and positive changes in zeta potential and floatability. The change of zeta potential, as a measure surface charge state of coal particles, from -15 mV to about 0 mV, after attrition for 30 minutes, confirms positive application of attrition. Zeta potential approaching 0 mV resulted in increasing floatability down to the real possibilities of the attrition process prior the coal flotation.

3

Badania laboratoryjne granulowania mułów węglowych

Feliks J.

Chemik

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2012

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Vol. 66, nr 5

388-395

PL

W artykule pokazano wyniki prób granulowania mułów węglowych pochodzących z Kopalni Węgla Kamiennego "Piast". Próby przeprowadzono na dwóch typach granulatorów: rynnowym granulatorze wibracyjnym i laboratoryjnym granulatorze talerzowym. W trakcie badań muły były mieszane z dodatkami obniżającymi ich wilgotność. Badania przeprowadzone były w celu określenia ilości dodatków koniecznych przy przemysłowym granulowaniu mułów.

EN

The article shows the results of tests of coal sludge granulation from the "Piast" coal mine. Tests conducted on two types of granulators: vibrating chute and laboratory plate granulator. In the study, the sludge was mixed with additives to lower the humidity. Studies were conducted to determine the amount of additives necessary for industrial sludge granulation.