Науковий вісник НГУ

Numerical studies on thermochemical processing of peat in a fixed layer

• 
• 

User Rating:  / 0

PoorBest 

Details

Category: Content №1 2022

Last Updated on 25 February 2022

Published on 30 November -0001

Hits: 4228

Authors:

B.B.Rokhman, orcid.org/0000-0002-1270-6102, Thermal Energy Technology Institute of the National Academy of Sciences of Ukraine, Kyiv, Ukraine, e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.

N.I.Dunayevska, orcid.org/0000-0003-3271-8204, Thermal Energy Technology Institute of the National Academy of Sciences of Ukraine, Kyiv, Ukraine, e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.

V.G.Vyfatnuik, orcid.org/0000-0003-0771-2652, Thermal Energy Technology Institute of the National Academy of Sciences of Ukraine, Kyiv, Ukraine, e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.

I.V.Beztsennyi, orcid.org/0000-0001-6536-5121, Thermal Energy Technology Institute of the National Academy of Sciences of Ukraine, Kyiv, Ukraine, e-mail: coalenergy@i.ua

повний текст / full article

Naukovyi Visnyk Natsionalnoho Hirnychoho Universytetu. 2022, (1): 038 - 045

https://doi.org/10.33271/nvngu/2022-1/038

Abstract:

Purpose. To investigate the gasification process of peat in gas generators with a fixed bed at a pressure of 1.5 MPa and create the initial conditions at the entrance to the waste burners required for combustion of the binary mixture.

Methodology. The objects of research were peat granules of Volyn peat. To calculate the process of gasification of peat gas, the constructed model of thermochemical processing of solid fuel, described in the first part of the work by the authors was used.

Findings. It is shown that in the area close to the upper boundary of the fixed bed, where the process of gasification of peat is stationary, there is a jump in the temperature of peat particles from 300 to 772C, in which the tar is practically not released, and thus the obtained pyrolysis gas contains CO₂, H₂O, H₂ and CO. The structural and physicochemical characteristics of gas generators are obtained and the initial conditions at the entrance to the discharge burners of the chamber furnace of the steam generator TPP-210A are formed.

Originality. It is shown that when the velocity of peat particles decreases, a slag bed is formed between the zone of maximum heat release and the grate, which consists of cooled ash particles, which protect the grate from overheating. With such an organization of the process it is possible to achieve the stationary process of gasification with mechanical incompletely burned material equal to zero.

Practical value. It is shown that with the help of the model of thermochemical processing of solid fuels it is possible to adjust the height of the dry distillation zone by changing the velocity of the dispersed phase and the rate of heterogeneous and homogeneous chemical reactions by changing the proportion of O₂ or H₂O air enrichment.

Keywords: fixed bed, coal, peat, thermal conductivity, steam air gasification, conductive and radiative heat exchange

References.

1. Roni, M.S., Chowdhury, S., Mamun, S., Marufuzzaman, M., Lein, W., & Johnson, S. (2017). Biomass co-firing technology with policies, challenges, and opportunities: A global review. Renewable and Sustainable Energy Reviews, 78, 1089-1101. https://doi.org/10.1016/j.rser.2017.05.023.

2. Zheng, S., Hu, Y., Wang, Z., & Cheng, X. (2020). Experimental investigation on ignition and burnout characteristics of semi-coke and bituminous coal blends. Journal of the Energy Institute. https://doi.org/10.1016/j.joei.2019.12.007.

3. Batenin, V.M., Ivanov, P.P., & Kovbasyuk, V.I. (2017). Improvement of thermodynamic efficiency of the humid biofuel application in the distributed generation power suppliers. High Temperature, 55(1), 70-74. https://doi.org/10.1134/s0018151x17010035.

4. Rokhman, B.B., Dunayevska, N.I., Vyfatnuik, V.G., & Beztsennyi, I.V. (2021). Co-firing of gas coal dust fine particles and synthetic peat gas. Part 1. Simulation of processes of steam-air gasification of peat in a fixed bed and combustion of dust and gas mix in a stream. Naukovyi Visnyk Natsionalnoho Hirnychoho Universytetu, (6), 57-65. https://doi.org/10.33271/nvngu/2021-6/057.

5. Rokhman, B., & Nekhamin, M. (2020). Theoretical study of nonstationary air gasification of solid fuel in a fixed bed at atmospheric pressure. Vidnovluvana Energetika, 1(60), 86-95. https://doi.org/10.36296/1819-8058.2020.1(60).86-9.

6. Gmes-Barea, A., & Leckner, B. (2010). Modeling of biomass gasification in fluidized bed. Progress in Energy and Combustion Science, 36, 449-509. https://doi.org/10.1016/j.pecs.2009.12.002.

7. Rokhman, B.B. (2020). Nonstationary steamoxygen gasifi cation of solid fuel in a fixed bed under pressure.Journal of Engineering Physics and Thermophysics, 93(3), 664-676. https://doi.org/10.1080/00986448808940254.

8. Park, S., Jeong, H., & Hwang, J. (2015).3-D CFD Modeling for Parametric Study in a 300-MWe One-Stage Oxygen-Blown Entrained-Bed Coal Gasifier. Energies, 8(5), 4216-236. https://doi.org/10.3390/en8054216.

9. Jeong, H.J., Seo, D.K., & Hwang, J. (2014).CFD modeling for coal size effect on coal gasification in a two-stage commercial entrained-bed gasifier with an improved char gasification model. Applied Energy, 123, 29-36. https://doi.org/10.1016/j.apenergy.2014.02.02.

10. Chua, Y.W., Yu, Y., & Wu, H. (2017). Thermal decomposition of pyrolytic lignin under inert conditions at low temperatures. Fuel, 200, 70-75. https://doi.org/10.1016/j.fuel.2017.03.035.

11. Tabakaev, R., Kanipa, I., Astafev, A., Dubinin, Y., Yazykov, N., Zavorin, A., & Yakovlev, V. (2019).Thermal enrichment of different types of biomass by low-temperature pyrolysis. Fuel, 245, 29-38. https://doi.org/10.1016/j.fuel.2019.02.049.

12. Khasraw, D., Spooner, S., Hage, H., Meijer, K., & Li, Z. (2021). Evaluation of devolatilization behavior of different carbonaceous materials under rapid heating for the novel HIsarna ironmaking process. Fuel, 292, 120329. https://doi.org/10.1016/j.fuel.2021.120329.

13. Ding, L., Wei, J., Dai, Z., Guo, Q., & Yu, G. (2016).Study on rapid pyrolysis and in-situ char gasification characteristics of coal and petroleum coke. International Journal of Hydrogen Energy, 41(38), 16823-16834. https://doi.org/10.1016/j.ijhydene.2016.07.10.

14. Zhou, Q., Zhang, Y., Zhang, J., & Ding, D. (2018). Evolution behaviors of nitrogen functionalities during fast CO₂-rich pyrolysis of coal. Fuel, 229, 135-143. https://doi.org/10.1016/j.fuel.2018.05.013.

• < Prev
• Next >