LABORATORY STUDY OF CARRYOVER DEPOSITION IN KRAFT RECOVERY BOILERS

The dynamic process of the impact of molten carryover particles on a t ube surface was studied in the laboratory using analogous liquids. Sem i-empirical models were developed to predict the maximum spread and th e rebound tendency of molten carryover upon impact. The model predicti ons agreed well with experimental data. The models may be used to pred ict the tendency of molten carryover to deposit on, or to bounce off, tube surfaces in the lower superheater region of recovery boilers. Thi s work also suggests that the ejection of small droplets during the im pact of molten carryover on a colder surface could be a mechanism for the production of the 10 to 100 mu m intermediate particles found in t he precipitator dust.