Fuel processing in a swirl flow: numerical modelling of combustion and gasification

This study presents the concept of a cyclone furnace for coal dust combustion and gasification under conditions of oxy-fuel combustion. A two-chamber design of the cyclone furnace allows for the separation of the process of heating, drying and devolatilization of fuel from processes of its combustion and gasification of carbon residue. The choice of process parameters helps control fuel gasification. Supplying the driving gas with a specific composition (O2, CO2) to the chamber PC1 ensures the control of temperature and composition of combustible gases obtained through gasification. These gases can be used as a fuel for power boilers and, consequently, allow for utilization of the oxy-fuel combustion technology in new or existing power boilers.

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Modelling of Coal Dust Gasification in a Cyclone Furnace under Oxy-fuel Combustion Conditions

Procedia Engineering ◽

10.1016/j.proeng.2016.08.392 ◽

2016 ◽

Vol 157 ◽

pp. 480-487 ◽

Cited By ~ 3

Author(s):

Robert Zarzycki ◽

Zbigniew Bis

Keyword(s):

Coal Dust ◽

Fuel Combustion ◽

Cyclone Furnace

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The Effects of Oxygen-Enriched Concentration in Combustion Air on Thermal Parameters for Forge Furnace

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.552.298 ◽

2014 ◽

Vol 552 ◽

pp. 298-303

Author(s):

Yue Guo ◽

Fang Qin Dai ◽

Ni Pan

Keyword(s):

Fuel Consumption ◽

Oxygen Concentration ◽

Thermal Parameter ◽

Heating Time ◽

Gas Production ◽

Fuel Combustion ◽

Thermal Parameters ◽

Radiation Coefficient ◽

Efficient Combustion ◽

Combustion Technology

Oxygen-enriched combustion technology is an energy efficient combustion technology, which can intensify the flame stability, increase the temperature and reduce fuel consumption. Aiming at forge furnace as research object, the effects of oxygen-enriched concentration in combustion air on thermal parameters is studied. The mainly thermal parameter included the fuel combustion procedure, thermal transfer, heating time and the amount of fuel combustion. The results show that with the oxygen concentration increasing, the gas emission coefficient and radiation coefficient is higher. While the heating time, the volume of combustion air requirement, flue gas production and fuel consumption is decreased. Additionally, the study suggests that forge furnace can obtain maximize economic benefit when oxygen concentration is about 30%.

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Modelling of the process of coal dust combustion in a cyclone furnace

Journal of Thermal Science ◽

10.1007/s11630-017-0929-4 ◽

2017 ◽

Vol 26 (2) ◽

pp. 192-198 ◽

Cited By ~ 8

Author(s):

Robert Zarzycki ◽

Zbigniew Bis

Keyword(s):

Coal Dust ◽

Cyclone Furnace

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USE OF TWO-STAGE FUEL COMBUSTION TECHNOLOGY TO MINIMIZE HAZARDOUS EMISSIONS AT KAZAKHSTAN TPP

NEWS OF THE NATIONAL ACADEMY OF SCIENCES OF THE REPUBLIC OF KAZAKHSTAN ◽

10.32014/2021.2518-1726.11 ◽

2021 ◽

Vol 335 (1) ◽

pp. 74-80

Author(s):

A.S. Askarova ◽

P. Safarik ◽

S.A. Bolegenova ◽

V.Yu. Maximov ◽

A.O. Nugymanova ◽

...

Keyword(s):

Combustion Chamber ◽

Mass Transfer Process ◽

Fuel Combustion ◽

Low Grade ◽

Two Stage ◽

Entire Volume ◽

Coal Fuel ◽

Air Supply ◽

Stage Combustion ◽

Combustion Technology

Studies have been carried out using numerical modeling methods to determine the effect of the introduction of a two-stage combustion technology (OFA technology) of high-ash Karaganda coal on the characteristics of combustion processes: aerodynamics of flows, temperature and concentration (COх, NOх) fields throughout the entire volume of the combustion chamber of the BKZ-75 boiler at Shakhtinskaya TPP and at the outlet from it. Comparison with the basic regime of combustion of pulverized coal fuel, when there is no air supply through additional injectors (OFA = 0%). To implement the technology of two-stage combustion, various regimes of additional air supply through injectors were chosen: OFA equals 0% (basic version, conventional combustion), 5%, 10%, 15%, 18%, 20%, 25% and 30% of total air volume required for fuel combustion. A comparative analysis of the main characteristics of the heat and mass transfer process in the combustion chamber for the investigated modes is carried out. It is shown that an increase in the volume of additional air supplied through the injectors up to 18% leads to a decrease in the concentration of nitrogen oxide NO by 25% in comparison with traditional combustion. A further increase in the volume of additional air leads to a deterioration in these indicators. The results obtained will make it possible to optimize the combustion of low-grade fuel in the combustion chamber of the BKZ-75 boiler, increase the efficiency of fuel burnout, reduce harmful emissions and introduce a two-stage combustion technology at other coal-fired TPPs.

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Experimental Study on NOx Reduction in Oxy-fuel Combustion Using Synthetic Coals with Pyridinic or Pyrrolic Nitrogen

Applied Sciences ◽

10.3390/app8122499 ◽

2018 ◽

Vol 8 (12) ◽

pp. 2499 ◽

Cited By ~ 3

Author(s):

Chang’an Wang ◽

Pengqian Wang ◽

Lin Zhao ◽

Yongbo Du ◽

Defu Che

Keyword(s):

Oxygen Content ◽

Power Plants ◽

Large Scale ◽

Nox Reduction ◽

Fuel Combustion ◽

Combustion Technology ◽

Carbon Dioxide Co2 ◽

No2 Formation ◽

The Impact ◽

Pyridinic Nitrogen

Oxy-fuel combustion technology can capture carbon dioxide (CO2) in the large-scale and greatly lower nitrogen oxides (NOx) emission in coal-fired power plants. However, the influence of inherent minerals on NOx reduction still remains unclear and the impact of oxy-fuel combustion on the transformation of different nitrogen functional groups has yet to be fully understood. The present work aims to obtain a further understanding of the NOx reduction during oxy-fuel combustion using synthetic coals with pyrrolic or pyridinic nitrogen. Compared to pyridinic nitrogen, more of the pyrrolic nitrogen in synthetic coal was converted to NOx. The conversion ratio of nitric oxide (NO) first increased significantly with the rising oxygen content and then trended to an asymptotically constant as the oxygen (O2) content varied between 10–50%. The nitrogen dioxide (NO2) formation was roughly proportional to the oxygen content. The NO2 conversion was increased with particle size but the case of NO showed a non-monotonic variation. The catalytic effects of sodium carbonate (Na2CO3), calcium carbonate (CaCO3), and ferric oxide (Fe2O3) on the transformation of pyridinic nitrogen to NO were independent of the combustion atmosphere, while the alteration from air to the oxy-fuel combustion led to a change of mineral catalytic effect on the oxidation of pyrrolic nitrogen within the coal matrix.

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Recent Advances in Coherent Anti-Stokes Raman Scattering of Carbon Dioxide for Combustion Diagnostic. (Article Review)

European Journal of Engineering Research and Science ◽

10.24018/ejers.2021.6.1.2301 ◽

2021 ◽

Vol 6 (1) ◽

pp. 42-47

Author(s):

Henry Misoi ◽

Josephat Tanui ◽

Patrick Wanjiru

Keyword(s):

Carbon Dioxide ◽

Raman Scattering ◽

Measurement Techniques ◽

Fuel Combustion ◽

Probe Molecule ◽

Detailed Knowledge ◽

Recent Advances ◽

Combustion Properties ◽

Combustion Technology ◽

Anti Stokes

The rising climatic degradation due to the emission of greenhouse gases is leading to emergence of clean combustion technology, oxy-fuel combustion to minimize the emissions of carbon dioxide into the atmosphere in combustion. Nitrogen molecules are used as probe molecule in laser-based combustion diagnostic in nitrogen rich air combustion. However, with the introduction of oxy-fuel combustion, carbon dioxide becomes the dominant molecule and has to be considered as probe molecule in combustion diagnostic. A detailed knowledge about thermodynamic properties: temperature, pressure and species concentration are necessary in optimization of combustion and minimizing the emission into the atmosphere. The non-intrusive spectroscopic measurement techniques are the most accurate methods to determine the combustion properties. The purpose of this review is to provide a brief overview of the recent advances made in application of coherent anti-Stokes Raman scattering of carbon dioxide for development of models for thermometry. However, there is no sufficient empirical data of time-domain S-branch Raman linewidth dependence on temperature that has been determined for pure-rotational coherent anti-Stokes Raman scattering of carbon dioxide and its mixtures for development of models for thermometry.

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