Testing of Experimental Heat Exchanger Flue Gas – Sludge

Paper in proceedings (conference paper)

en

Sludge is a suitable alternative fuel, and can be combusted without auxiliary fuel. To achieve this target, heating value of sludge needs to be increased. Thus the water content of sludge needs to be reduced. In literature low thermal disintegration is named to be one suitable possibility reducing water content of sludge. In case of thermal sludge utilization, heat can be withdrawn from flue gas and transferred into sludge. Transferring heat from flue gas into sludge can be done by means of flue gas – sludge heat exchanger or water – sludge heat exchanger. Existing heat exchanger in sludge applications are mostly used for heat recovery or digester pre heating. Thus existing heat exchangers are designed for small temperature differences across the fluids. In flue gas – sludge application fouling on the sludge side was considered to be a serious problem. Thus tests had to be carried out to evaluate if fouling is a serious problem at obtained temperature differences. For this purpose an experimental heat exchanger "flue gas – sludge" was designed and tested. To evaluate former measured sludge properties, heat transfer was also determined analytically as well as in CFD model and compared with the experimental data. The results are presented in tables, diagrams and pictures.

heat exchanger, sewage sludge, CFD model

2007-10-15

ČSCHI

Praha

80-86059-47-2

Sborník 54. konference chemického a procesního inženýrství CHISA 2007

C2.3–

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