The diploma thesis deals with multitube cyclone changes leading to improve separating efficiency of solid particles. The thesis begins with theoretical part, in which the attributes and types of solid particle separators focusing on cyclones are presented. The practical part begins with separating efficiency and pressure drop calculation of the specific multitube cyclone. Subsequently the separating problem is explained and the changes leading to eliminating this problem are presented and evaluated. In the last and main part of thesis the design project including piping design and fan choice is created.