In order to deal with serious abrasion on upper catalyst layer at both sides of beam in an SCR denitration device and ensure the equipment's efficient and safe operation

field test combined with numerical simulation was conducted to analyze the flow field inside the denitration system for a 660 MW unit boiler.The reasons for serious abrasion of the upper catalyst layer around beam area were investigated.The experimental results dovetailed nicely with that of the numerical simulation

and they both agreed well with the actual abrasion situation.The results indicate that the abrasion of the catalyst is directly related to the flow field above the catalyst layer.The gas stream after turning flue is separated by the supporting beams so that a high-speed downstream airflow is formed at the front side of the beam

which is then divided into two airflows with different directions at the catalyst layer entrance.One of the airflow moves down in the vertical direction while the other deflects horizontally due to the vortexes.As a result

the catalyst at both sides of the beam is worn seriously.