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Show SLURRY COMBUSTION USING AN ULTRASONIC BURNER C. F. Yin A Thermal Transfer Corporation <^> &- y^s^Xr^-^*-**> Monroeville, Pennsylvania A ^ %Ay^r>*^^^ ^-> H. Bormann Kali-Chemie A.G. Hannover, Germany ABSTRACT A slurry combustion system incorporating a burner with ultrasonic atomizing nozzle is developed. Successful tests were made in the full scale operation of a rotary kiln and a process steam boiler where 60/40 coal-oil mixture and other very viscous fuels were burned. The heart of this system is the DUMAG burner with an ultrasonic atomizing nozzle, where an ultrasonic field is generated by compressed air or steam through a ring-shaped resonance chamber. Fine atomization can be achieved for viscous liquid or solid/liquid mixtures. The fuels exit from the nozzle through a large opening so that clogging and erosion can be prevented. The burner is also capable of burning low BTU liquid with supplemental oil or gas. Operating tests showed that for complete coal-oil mixture (COM) combustion, coal particles of less than 100 m are necessary. A wet-grinding system was used in the preparation of the COM to minimize the problems of explosion and segregation. The mill is a grinding, mixing, and pumping device in one unit which prepares the slurry only as required. This system is applicable to the conversion of existing oil-firing combustion systems into firing slurries without high investment cost or sacrificing the capacity of the installation. 16-1 |