Based on the analysis of pyrolysis process, a new vertical cracking tower was designed, which could pyrolyze waste tires into carbon black, liquid oil and fuel gas. Heat transfer in new cracking tower is entirely conduction controlled and rotational velocity of scraper and medium temperature are the most important factors influencing heat transfer property determining pyrolysis rate. The experimental results show pyrolysis rate of waste tires increases with the increase of rotational velocity and medium temperature, but it has also been found rotational velocity up to such a boundary value has little influence on the heat-transfer property and excessive medium temperature will waste energy and affect carbon black quality. In addition, a simplified model was based on the particle heat transfer model to describe the heat transfer process of cracking tower, which could be applied to calculate heat transfer coefficient under the conditions that thermal medium had no phase change and was consistent into all hollow disks. The theoretical prediction was shown to be in satisfactory agreement with experimental data from 3000t/y pilot-plant.
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