A survey of tire burning technology for the cement industry

Tires as a fuel have gained popularity in the cement industry since their beginnings in the 1970s. This paper first gives an overview of tire generation and usage statistics as well as alternate uses. A detailed chemical analysis is given as well as an idea on variations in heat values. Minor constituents important to the cement industry are identified. Subsequently, the tire is followed on its path through the cement plant, from receipt and transportation of both whole and chipped tires to the kiln. The kiln section describes advantages and disadvantages of whole and chipped tire uses, broken down by major kiln type (long dry, long wet, preheater and preheater/precalciners). It includes the results of a questionnaire, which obtained practical information on substitution rates, emissions, quality, specific heat consumption and limiting factors from 23 cement plants burning tires across North America