The invention discloses an anti-blocking device of a 
system for rectifying poly-methoxy 
dibutyl ether and a method for refining the same. The 
system comprises a rectifying 
tower, a 
reboiler, a condensation cooler, a 
reflux tank and a 
reflux pump which are sequentially communicated with one another. The 
reflux pump is communicated with the rectifying 
tower. The method includes (1), delivering to-be-separated mixtures into the rectifying 
tower from the middle of the rectifying tower, separating the to-be-separated mixtures under the conditions of the pressures 
ranging from -0.01 MPa to 1.0 MPa, the tower top temperatures 
ranging from 90 DEG C to 160 DEG C and the tower bottom temperatures 
ranging from 120 DEG C to 180 DEG C, extracting poly-methoxy 
dibutyl ether solution from a tower bottom and extracting mixture steam from a tower top; (2), allowing the mixture steam to flow into the condensation cooler from a material steam inlet, cooling the mixture steam at the temperatures ranging from 80 DEG C to 120 DEG C to obtain condensed liquid, then allowing the condensed liquid to flow into the reflux tank from a material liquid outlet, allowing a part of the condensed liquid to flow back into the rectifying tower to continue to be rectified and extracting portions which do not flow back to the rectifying tower from the 
system. The anti-blocking device and the method have the advantages that the problem of easiness in blocking equipment can be effectively solved, and the separation purity of the poly-methoxy 
dibutyl ether can be enhanced.