External circulation ash calcium grinding and grading system

The utility model discloses an external circulation ash calcium grinding and grading system. The pulverizer comprises a storage hopper, a pulverizing main machine, a finished product collector and anair blower, scattering and grading device, the scattering and grading device comprises a slag hopper, a scattering machine and a grading machine which are sequentially mounted from bottom to top; a discharge port of the grader is communicated with a feed port of the finished product collector through an air outlet pipe; two paths of slag outlets of the slag hopper are communicated; wherein one path of slag discharge port is communicated with a feed port of the main grinding machine through a first screw feeder, and the other path of slag discharge port can directly discharge slag; wherein a discharge port of the powder grinding main machine is communicated with an air inlet in a hopper body of the slag hopper through an air inlet pipe, a discharge port of the storage hopper is communicatedwith a feed port of the s