Material to be treated such as garbage is charged into a first rotary kiln 14 to be mainly dehydrated and charged into a second rotary kiln 18 to be carbonized. 13 and VC satisfying an expression \u22125=\u2212=2 provides an excellent suppressing effect on ghost images and hardly causes a ghost phenomenon even when it is mounted on a color electrophotographic apparatus or an electrophotographic apparatus having no electrostatic removal device. A first electrohydraulic valve is connected to receive the first output signal from the microprocessor, and connected to position the boom assembly in response to the first output signal. 6 mm, the bezel being designed to satisfy the following inequality t\u22670. Cross-sections having parting lines may have fin-like protuberances that result in less material being used for the same overall outline as a round cross-section.