DYNAMIC MODELING OF INDUSTRIAL SO2 OXIDATION REACTORS .1. MODEL OF HOT AND COLD START-UPS OF THE PLANT

The paper describes a comparison of some results computed using a mathematical dynamic model of a single reactor bed with real temperature unsteady state transients, measured in a large industrial scale SO2 oxidation reactor. Problems of the dynamic modelling of complete oxidation plants, including a heat exchange section and a start-up installation are discussed in the next section of the paper. As a basis for comparison some start-up dynamic transients were analysed. The analysis shows that the model (two-phase model for heat transfer and homogeneous model for mass transfer) is sufficient for qualitative analysis of the problem. The problems of obtaining reliable parameters for simulation as well as parameter sensitivity of the model are also described. The plant is modelled using the dynamic flowsheeting simulator DYNAM, whose algorithm is presented against a background of similar simulators known from the literature. The major part of the paper presents the results of the identification of the model based on an actual industrial plant, together with the start-up analysis concerning the SO, oxidation plant. The analysis has been aimed at minimizing both the emission Of SO2 during start-up and its duration. The results are given for the various modes of the start-up operation.