Bed-to-wall heat ransfer in a supercritical circulating fluidised bed boiler

• Autorzy: Błaszczuk A. , Nowak W. , Jagodzik S.

Identyfikatory

DOI

10.2478/cpe-2014-0015

• Języki publikacji: EN

Abstrakty

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 x 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 x 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.

Słowa kluczowe

EN

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

PL

współczynnik przenoszenia ciepła; gęstość zawiesiny; temperatura pieca; kocioł CFB w stanie nadkrytycznym

• Wydawca: Komitet Inżynierii Chemicznej i Procesowej Polskiej Akademii Nauk
• Czasopismo: Chemical and Process Engineering
• Rocznik: 2014
• Tom: Vol. 35, nr 2
• Strony: 191--204
• Opis fizyczny: Bibliogr. 27 poz., tab., rys.

Twórcy

autor

Błaszczuk A.

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

autor

Nowak W.

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

autor

Jagodzik S.

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

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