NOVELTY - A composting apparatus has primary, secondary fermenters (1,2) for performing sequential fermentation of raw material, secondary fermenter air fan for supplying air or fermentation waste gas (WG) to (2), primary fermenter air fan for supplying WG from (2) to (1), deodorant burner (3) treated with WG ejected from (1) and ventilator (6) for supplying part of processed gas ejected from (3) to (1).    USE - For carrying out fermentation of organic wastes such as sewage sludge.    ADVANTAGE - The amount of waste gas ejected from the composting apparatus is reduced as part of waste gas ejected is utilized as heat energy for heating primary fermenter. The deodorizing apparatus is made compact and operating cost is reduced. As a thermal storage burner is used as deodorizing unit, thermal efficiency is raised. The processed gas of burner is circulated for heating the primary fermenter. As the processed gas from thermal storage burner is used effectively, temperature of the primary fermenter is maintained more than the moisture content saturation temperature, thereby reducing the amount of heat supply to the apparatus. Construction cost, operating cost and size of the composting apparatus are reduced.    DETAILED DESCRIPTION - A composting apparatus has primary fermenter carrying out primary fermentation of the raw material, secondary fermenter carrying out secondary fermentation of primary fermentation material and secondary fermenter air fan for supplying air or fermentation waste gas to fermenter (2). Primary fermenter air fan supplies gas ejected from fermenter (2) to fermenter (1) and thermal storage burner (3) is treated with gas ejected from fermenter (1). A ventilating fan (6) supplies part of processed gas ejected from burner (3) to fermenter (1).    DESCRIPTION OF DRAWING(S) - The figure shows systematic diagram of the composting apparatus. (Drawing includes non-English language).    Primary fermenter (1)    Secondary fermenter (2)    Thermal storage burner (3)    Secondary fermenter air fan (4)    Primary fermenter air fan (5)    Ventilating fan (6)