This paper uses heat transfer models to monitor fouling from ash in a coal-fired power generation boiler. In particular, a counterflow heat exchanger model for the economiser and a periodic flow model for the airheater are developed. Model inputs are local measurements of flow, temperature, etc, and the outputs are fouling indices in real time.
Results from tests on a transient-load full-scale power station are piesented for both models. Recurring fouling patterns are shown to suggest relationships with time, load and with changes in the in-service cleaning system.
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