Shevchenko G.O., Cholyshkina V.V., Sukharyev V.V., Kurilov V.S. Processing of fly ash from thermal power plants by means of mechanical classification by size

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Parent Category: Geo-Technical Mechanics, 2022

Category: Geo-Technical Mechanics, 2022, № 160

Geoteh. meh. 2022, 160, 133-140

https://doi.org/10.15407/geotm2022.160.133

 

PROCESSING OF FLY ASH FROM THERMAL POWER PLANTS BY MEANS OF MECHANICAL

¹Shevchenko G.O., ¹Cholyshkina V.V., ¹Sukharyev V.V., ¹Kurilov V.S.

¹Institute of Geotechnical Mechanics named by N. Poljakov of National Academy of Sciences of Ukraine 

UDC 622.74

Language: English

Abstract. The processing of ash and sludge waste from coal-fired thermal power plants (TPP) is an urgent problem. Solving this problem reduces the operating costs for the maintenance of ash storage facilities, allows to obtain new types of products, reduces the environmental impact. The purpose of the study is to establish the granulometric composition of the wet storage fly ash for several TPPs, to determine the possibility of obtaining a carbon-rich intermediate product (industrial product) by means of mechanical classification. This method involves combining rich and close-sized classes into industrial products and removing the remaining lean classes into waste. Two most common types of ash and sludge raw materials have been studied. The first one with low carbon content in the coarse and finest classes. The second type is high carbon content in all the size classes except the finest ones. It is established that the method applied leads to a twofold increase of the coal concentration in the industrial product. For the ash of the Prydniprovska and Kurakhivska TPPs, the industrial product has a carbon content of about 40% with a carbon content of 12-15% in the waste. An industrial product with a carbon content of 57% was obtained from the ash of Chernihivska TPP, the carbon content within waste is about 20%. The advantage of the obtained industrial product is that the absence of the finest classes alleviates its dressing by means flotation and gravity methods. The resultant waste, both in terms of carbon content and their size, meets the standards for fly ash of TPP for the manufacture of lightweight concrete and could be used in industry. The output of waste ranges from 45 to 80% of the initial raw material. The study also considers an option of selective extraction of high grade raw materials with a carbon content that exceeds 35% at the ash storage facility. For such raw materials, the method of isolation of the productive class allows to obtain a finished coal product with  carbon content within the range of 70-72% for an output of 22-25% from the initial sample. The waste contains about 25% carbon. In this case, the industrial product is a ready-to-use pulverized fuel for secondary use at TPP. It is also possible to use it in the form of coal briquettes. Tentative assessment proves that this technology seems to be profitable, since the costs of raw materials lifting process as well as drying and vibratory screening process do not exceed the costs of coal mining, transportation and preparation processes for the coal combustion at TPP.
Keywords: ash, carbon, intermediate product, waste.

REFERENCES:

1. Nadutiy, V.P., Sevastyanov, V.S. and  Kostyrya, S.V. (2017), “Justification of the expediency of complex processing of fly ash of thermal power plants”, Geo-Technical Mechanics,  131, pp. 59-66.

2. Ravich, M.B. (1977), Fuel use efficiency, Nauka, Moscow.

3. Nadutiy, V.P., Lapshin, E.S. and Khmelenko, I.P. (2009), “Analysis of the vibro-shock mode of motion of the screening screen surface”, J. Vibrations in engineering and technology, VSAU,  Vinnytsia, 2(54), pp. 69–72.

4. Shevchenko, G., Shevchenko, V. and Kadyrov, A. (2009), “Poly-frequency screens for separation of thin bulk materials”, J. Zbagachennya korisnikh kopalin, NGU, Dnepropetrovsk, 38 (79), pp. 44–50.

5.  Bulat, A., Shevchenko, G., Shevchenko, V. and Bokiy, B. (2016), “The results of industrial tests of the technology of cleaning drilling fluids on the poly-frequency screen of the MVG”, J. Prospecting and Development of Oil and Gas Fields, 2(59), pp. 72–80.

6. Ivanov, I.I. (1985), Light concrete with the use of ash power plants, Stroyizdat., Moscow.

7. state building committee USSA (1991), GOST 25818-91, Interstate standard of fly ash of thermal power plants for concrete. Technical conditions, Moscow, 12, available at: https://meganorm.ru/Data2 /1/4294853/4294853144.pdf (Accessed 13 July 2022).

8. Kieselstein, L., Dubov, I., Shpitsgluz, A. and Parada, S. (1995), Components of ashes and slag’s of thermal power plants, Energoatomizdat, Moscow.

About authors:

Shevchenko Georgy Oleksandrovych, Doctor of Technical Sciences (D.Sc.), Head of Department of Mechanics of Mineral Processing Machines and Processes, Institute of Geotechnical Mechanics named by N. Poljakov of National Academy of Sciences of Ukraine (IGTM NAS of Ukraine), Dnipro, Ukraine, This email address is being protected from spambots. You need JavaScript enabled to view it.

Sukharyev Vitalii Vitaliiovych, Candidate of Technical Sciences (Ph.D.), Senior Researcher in Department of Mechanics of Mineral Processing Machines and Processes, Institute of Geotechnical Mechanics named by N. Poljakov of National Academy of Sciences of Ukraine (IGTM NAS of Ukraine), Dnipro, Ukraine, This email address is being protected from spambots. You need JavaScript enabled to view it.

Cholyshkina Valentina Vasylivna, Candidate of Technical Sciences (Ph.D.), Senior Researcher in Department of Mechanics of Mineral Processing Machines and Processes, Institute of Geotechnical Mechanics named by N. Poljakov of National Academy of Sciences of Ukraine (IGTM NAS of Ukraine), Dnipro, Ukraine, This email address is being protected from spambots. You need JavaScript enabled to view it.

Kurilov Vladyslav Serhiiovych, Engineer of Department of Mechanics of Mineral Processing Machines and Processes, Institute of Geotechnical Mechanics named by N. Poljakov of National Academy of Sciences of Ukraine (IGTM NAS of Ukraine), Dnipro, Ukraine, This email address is being protected from spambots. You need JavaScript enabled to view it.

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