OCR Text |
Show 1~ ---------------------------------------, -Test 6 1000 [ill Test 5 II Test 7 100 ImI Test 4 10 1 0.1 0.01 ~ u e e e 1-4 "'0 ~ - e u § '8 =' =' =' 00 .. ~ JJ ~ ~ =' ~ = ·S ·s 0.. ~ u '8 .~ tI} 0 ..... < ~ ~ Z ~ "i ~ u ~ - ~ 0 0 CQ U U CI.) Figure 9. Metals content of feed materials that will result from the evolution of carbon from the ash. The normalized enrichment will indicate the tendency of a metal to migrate from one incinerator effluent to another. The enrichment of metals in the residual ash normalized by the enrichment of chromium is shown in Figure 10. The metals content in the residuals was lower than the feed than in the waste in almost every case. Higher temperatures appeared to promote the removal of metals from the residuals. The temperature effect was most pronounced for antimony, arsenic, cadmium, lead and zinc. Mercury is always removed at very high efficiencies for all temperatures used. The emitted metals were sampled. Figures 11 shows the normalized enrichment of metals in the tests. Temperature has a strong impact on the normalized enrichment of metals in the emitted particles. At l0000F, the metals are only slightly more concentrated in the emitted particles than in the waste. At higher temperatures, the enrichment increases significantly. CHARACTERISTICS OF FULL·SCALE SYSTEM The bench-scale tests indicated that moderate kiln temperatures would be required to ensure the removal of organics materials from the residual ash for treatment times of about 1 hour. At all of the conditions examined, significant amounts of toxic organic compounds were detected in the kiln's exhaust gas. An afterburner would be required to ensure that emissions were acceptable. The organic emissions appeared to independent of the operating conditions. -17- |