Investigations of operation problems at a 200 MWe PF boiler

• Authors: Sandile Peta , Chris du Toit , Reshendren Naidoo , Walter Schmitz , Louis Jestin
• Languages of publication: EN

Abstracts

EN

To minimize oxides of nitrogen (NOx) emission, maximize boiler combustion efficiency, achieve safe and reliable burner combustion, it is crucial to master global boiler and at-the-burner control of fuel and air flows. Non-uniform pulverized fuel (PF) and air flows to burners reduce flame stability and pose risk to boiler safety by risk of reverse flue gas and fuel flow into burners. This paper presents integrated techniques implemented at pilot ESKOM power plants for the determination of global boiler air/flue gas distribution, wind-box air distribution and measures for making uniform the flow being delivered to burners within a wind-box system. This is achieved by Process Flow Modelling, at-the-burner static pressure measurements and CFD characterization. Global boiler mass and energy balances combined with validated site measurements are used in an integrated approach to calculate the total (stoichiometric + excess) air mass flow rate required to burn the coal quality being fired, determine the actual quantity of air that flows through the burners and the furnace ingress air. CFD analysis and use of at-the-burner static, total pressure and temperature measurements are utilized in a 2-pronged approach to determine root-causes for burner fires and to evaluate secondary air distribution between burners.

Keywords

EN

process flow modelling; mass and energy balance; furnace CFD modelling; PF swirl burner

• Publisher: De Gruyter Open
• Journal: Chemical and Process Engineering
• Year: 2015
• Volume: 36
• Issue: 3
• Pages: 305-320

Dates

published

1 - 9 - 2015

received

11 - 3 - 2015

revised

21 - 7 - 2015

accepted

23 - 7 - 2015

online

5 - 11 - 2015

Contributors

author

Sandile Peta

• ESKOM SOC, Group Technology Engineering, Boiler Auxiliaries, 1 Simba Rd, Sunninghill, Johannesburg, South Africa

author

Chris du Toit

• ESKOM SOC, Generation Engineering, Camden Power Plant, Ermelo, South Africa

author

Reshendren Naidoo

• University of Witwatersrand, School of Mechanical, Industrial and Aeronautical Engineering, Johannesburg, South Africa

author

Walter Schmitz

• University of Witwatersrand, School of Mechanical, Industrial and Aeronautical Engineering, Johannesburg, South Africa

author

Louis Jestin

• University of Cape Town, Faculty of Engineering and the Built Environment, Cape Town, South Africa

References

• Archary H., Jestin L.M., Roohani H., 2012. Online measurement and condition based maintenance of pulverised fuel vertical spindle mills. POWER-GEN AFRICA 2012. Johannesburg, South Africa, 6-8 November 2012.
• Brown R., 2004. Coal and air flow measurement and control at Allegheny’s Armstrong Station. EPRI, March 29, 2004. Available at: http://www.epri.com/abstracts/Pages/ProductAbstract.aspx?ProductId=000000000001009374
• Department of Trade and Industry, 2001. Technology status report. Pulverised fuel (PF) flow measurement and control methods for utility boilers. Available at: http://webarchive.nationalarchives.gov.uk/+/http://www.berr.gov.uk/files/file19294.pdf.
• Peta S., du Toit C., Jestin L.M., Roohani H., 2012. Burner flow controls for safe, reliable, complete and clean combustion. POWER-GEN AFRICA 2012. Johannesburg, South Africa, 6-8 November 2012. van der Merwe J.C., Roohani H., Jestin L.M., Simonin O., van Wyk C., Archary H., 2012. Mastering pulverised fuel distribution to low-NOx burners for safety and environmental protection. POWER-GEN AFRICA 2012.
• Johannesburg, South Africa, 6-8 November 2012.
• Winkler H., 2006. Energy policies for sustainable development in South Africa. Options for the future. Energy Research Centre, University of Cape Town. Available at: https://www.iaea.org/OurWork/ST/NE/Pess/assets/South_Africa_Report_May06.pdf.

Identifiers

DOI

10.1515/cpe-2015-0021