This paper describes the modelling of an industrial chlorination tower by a multiple model approach. Two local model structures, local ARX and local Laguerre models, are considered for predicting the brightness of the pulp at the output of the tower. Real data are used to assess the performance of these local model structures. The results show that both types of local models can provide a satisfactory level of performance over a wide range of operating conditions. However, local Laguerre models can model this process using fewer parameters than the ARX one.