Bed-To-Wall Heat Transfer in a Supercritical Circulating Fluidised Bed Boiler

• Authors: Artur Błaszczuk , Wojciech Nowak , Szymon Jagodzik
• Languages of publication: EN

Abstracts

EN

The purpose of this work is to find a correlation for heat transfer to walls in a 1296 t/h supercritical circulating fluidised bed (CFB) boiler. The effect of bed-to-wall heat transfer coefficient in a long active heat transfer surface was discussed, excluding the radiation component. Experiments for four different unit loads (i.e. 100% MCR, 80% MCR, 60% MCR and 40% MCR) were conducted at a constant excess air ratio and high level of bed pressure (ca. 6 kPa) in each test run. The empirical correlation of the heat transfer coefficient in a large-scale CFB boiler was mainly determined by two key operating parameters, suspension density and bed temperature. Furthermore, data processing was used in order to develop empirical correlation ranges between 3.05 to 5.35 m·s-1 for gas superficial velocity, 0.25 to 0.51 for the ratio of the secondary to the primary air, 1028 to 1137K for bed temperature inside the furnace chamber of a commercial CFB boiler, and 1.20 to 553 kg·m-3 for suspension density. The suspension density was specified on the base of pressure measurements inside the boiler’s combustion chamber using pressure sensors. Pressure measurements were collected at the measuring ports situated on the front wall of the combustion chamber. The obtained correlation of the heat transfer coefficient is in agreement with the data obtained from typical industrial CFB boilers.

Keywords

EN

heat transfer coefficient; suspension density; furnace temperature; circulating fluidised bed; supercritical CFB boiler; cluster renewal approach

• Publisher: De Gruyter Open
• Journal: Chemical and Process Engineering
• Year: 2014
• Volume: 35
• Issue: 2
• Pages: 191-204

Dates

published

1 - 6 - 2014

online

10 - 7 - 2014

accepted

13 - 3 - 2014

revised

29 - 1 - 2014

received

4 - 3 - 2013

Contributors

author

Artur Błaszczuk

• Częstochowa University of Technology, Institute of Advanced Energy Technologies, Dabrowskiego 73, 42-200 Częstochowa, Poland

author

Wojciech Nowak

• Częstochowa University of Technology, Institute of Advanced Energy Technologies, Dabrowskiego 73, 42-200 Częstochowa, Poland

author

Szymon Jagodzik

• Tauron Generation S.A., Łagisza Power Plant, Pokoju 14, 42-504 Będzin, Poland

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Identifiers

DOI

10.2478/cpe-2014-0015