Enhancement of heat transfer during rubber pyrolysis process

Abstract

Pyrolysis can transform the waste rubber into high value oil, gas and solid carbon, which is a green and environmental protection treatment method. However, due to the poor thermal conductivity of rubber and easy to bond to the reactor wall when heated, the heat transfer efficiency of rubber is low, which has seriously affected the industrialization process of waste rubber pyrolysis. In order to solve this problem, Internal Circulational Thermal Dispersion Technology (ICTDT) was proposed in this study. A certain number of spherical heat-conducting media made of alumina oxide was added into the rotary kiln, forming more high temperature heat source, making the heat transfer efficiency of the rubber in the rotary kiln greatly increase. Besides, the friction between heat-conducting media and the wall of rotary kiln or rubber inhibited the formation of the coking center, thus reducing coking production to a certain extent. The improvement of coking also improved the heat transfer efficiency of pyrolysis process. Through experiments and numerical simulations, the influence of diameter and filling rate of the heat-conducting media on the distribution of pyrolysis products and the temperature rise of the rotary kiln was analyzed, which is expected to provide a feasible method and scientific guidance for the industrialization of waste rubber pyrolysis.