Flue dust samples from the steel reclamation plants contained PCDD/F ranging from 3.5 to 6.7 ng TE (BGA)/g [3.5 ‐ 6.0ng I‐TEQ/g]. PCDD/F in flue gas ranged from 0.9 to 2.5 ng TE (BGA)/Nm3 [0.9 ‐ 2.7 ng I‐TEQ/Nm3] resp. 0.1 to 3.3 ng TE CBGA)/Nm3 [0.1 ‐2.3 ng I‐TEQ/Nm3]. PCDD/F in clean gas ranged from 0.03 to 0.1 ng TE (BGA)/Nm3 [0.02 ‐ 0.1 ng I‐TEQ/Nm3] resp. 0.4 ng TE (BGA)/Nm3 [0.2 ng I‐TEQ/ Nm3]. Highest contamination (in TE) always occurred after addition of scrap with a high content of non‐metals resp. of MWI scrap. Although these PCDD/F concentrations in clean gas lie 5‐to 400‐fold under present emissions of MWIs (1 to 10 ng I‐TEQ/Nm3), these results are no argument for neglecting this source as potential environmental input of PCDD/F. Here, a look at the freights is necessary.
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