Incineration is not a new technology and has been used to destroy organic hazardous waste for many years. Nevertheless, variability in waste composition and the severity of the incineration operating conditions may result in many practical operating problems, high maintenance requirements and equipment unreliability. Moreover, a large number of constraints must be satisfied. These constraints are imposed by permit, by design and by operating practice. The goal of this work is to present a dynamic model which is able to follow large variations in process conditions and to be of practical value from a control point of view. This paper deals in particular with the development of a dynamic model which describes the behavior of a rotary kiln (primary combustion chamber with heterogeneous combustion) as well as the corresponding afterburner system (secondary combustion chamber with homogeneous combustion) followed by a heat recovery system which completes the hot section of a typical incineration plant. Special attention was devoted to a start-up procedure which was used as a specific application, to check the robustness and reliability of the model itself effectively. In addition, a number of comparisons with experimental data available from commercial units are reported to complete the model validation under ordinary feeding conditions.