Abstract: Structure-reasonable rotary impeller head has been investigated by the simulated test within water. A ceramic impeller head is manufactured and the degassing test in aluminium casting alloy in laboratory condition proceeded. Results showed that not only the efficiency of refining is good but the constitution and temperature of the melt become more homogenious as well, because the purging bubbles are very fine and unformly distributed and their staying within the melt is longer. Hence it is realy an advanced refining technique.