Experimental study on the compact splitting-type returning ash heat exchanger of CFB boilers

The external heat exchanger(EHE) is the key technology for large-scale CFB boilers.In order to develop the large CFB boiler technology with independent intellectual property rights and meet the need of home-made 200 MW CFB,an external compact splitting-type returning ash heat exchanger was developed.It is of integrated structure to control the circulating ash flow and realize the cooling and returning function.The CHE characteristic study was carried out on a 4 MW test bench for the splitting,regulating and heat transferring performance and a heat transfer calculation model was established for the practical design of boilers.The results provide a useful reference for the design of home-made 200 MW CFB boiler.