| 摘要 |
<p>PROBLEM TO BE SOLVED: To easily convert polluted soil containing PCB into harmless one at a low cost and to use all of the treated material by using soil containing PCB as the raw material for the production of cement clinker. SOLUTION: Soil containing PCB can be used by up to 3.5 wt.% in a production source material. The PCB content in the soil to be used is about <=1,000 ppm. Thereby, when the soil containing PCB in a higher concn. is to be used, it is preferable to directly feed a small amt. of the soil to a kiln for the production of cement, or to treat the soil by other methods for the decomposition of PCB. A clay component is compounded by about 14 wt.% into the source material for the production of cement clinker, and a part of the clay corresponding to <=25% of the clay to be compounded can be replaced by the soil containing PCB. As for a device for the production to be used, devices used for general production of cement can be used. By calcining the soil containing PCB with other source materials at 1,300 to 1,450 deg.C, PCB can be completely decomposed.</p> |
