Thermal Destruction of Biological Sludge in a Rotary Kiln

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the particulate emitted were finer than ten microns. The average median particle size was 1.2 microns and on the average 53 percent of the particles were below two microns. These figures indicate that particulate removal will present the biggest challenge to the flue gas treatment system. TABLE V STACK PARTICLE SIZE DATA SUMMARY RUN MEDIAN PARTICLE % OF PARTICLES % OF PARTICLES SIZE IN MICRONS LESS THAN 2 LESS THAN 10 MICRONS MICRONS 1A 1.37 55.0 87.2 1B 1.22 57.0 87.0 2A 1.95 50.5 82.5 2B 2.10 49.0 79.7 3A 1.45 53.0 83.5 TABLE VI STACK PARTICULATE ANALYSES RUN 1A RUN 2A RUN 3A MICRON CUM% MICRON CUM% MICRON CUM% 13.99 100.0 15.0 100.0 14.94 100.00 8.76 87.7 9.40 82.0 9.36 82.5 5.97 77.2 6.40 72.7 6.37 73.1 4.09 69.4 4.39 64.0 4.37 65.6 2.66 58.7 2.85 54.3 2.84 56.6 1.37 50.1 1.47 47.1 1.46 50.8 0.87 39.9 0.94 37.7 0.93 39.8 0.67 32.5 0.72 27.0 0.72 33.6 <0.67 0.1 <0.72 0.2 <0.72 0.10 Tables VII and VIII present the results of the metals analyses performed on the feed samples and stack particulate respectively. On the average the metals content of the stack particulate from run 3A is less than the that of 2A+2B, which is less than that of 1A + lB. This most likely indicates the absence of solid phase steady state in the kiln. If this were true, it would mean that we could expect more metal fumes in the stack, and less metal adsorption onto the particulate during 8