DEVELOPMENT OF AN INDUSTRIAL MODEL OF RAPPING - EFFECT ON THE COLLECTING EFFICIENCY

The rapping process is not yet well understood for two main reasons : on the one hand the objectives of the research have been focused for many years on a empirical optimisation of rapping, the knowledge of generation and evolution of the layer was considering as less significant, on the other hand the evolution of the dust layer is difficult to reproduce in a laboratory physical model. The experimental study of the mass balance in an industrial esp pilot provided precious data and made the development of the model possible. It has been compared with good agreement with an industrial esp test in a 500MW power plant. The model of rapping plates has been developed and integrated in the new version of the EDF-IRS software ORCHIDEE to help the plant staff to optimise their rapping sequences. ORCHIDEE is a user friendly software and we succeed to integrate the rapping model with only geometrical and operational data like the different times of rapping operation, the variation of these times influences the layer thickness on the plate and finally the collecting efficiency.