The return feeder generally is composed of standpipe and valve. The main functions of the standpipe are to prevent the reverse alteration of gas and form enough differential pressure to overcome the pressure difference between the separator and the hearth. The function of the valve is to regulate and open/close the solid particles flow.  

Function of Return Feeder :

1. Continuously and stably convey the recycling materials separated from the cyclone separator back to the hearth.

2. Provide the sealing of the negative pressure of cyclone separator and the pressure of the combustion chamber.