An incinerator with a main combustion chamber leading directly to two consecutive reburn stages. The main combustion chamber accepts bulk refuse onto a hearth floor. Air jets within the floor and near the roofline provide a generally stoichiometric amount of air for the burning refuse. Of this air, 75% emanates from the nozzles located in the floor. For the designed amount of refuse, the main chamber has a sufficient area to maintain the ratio for the expected heat to the square area to less than about 100,000 Btu/sq.ft. hr. Similarly, the ratio of the main chamber's volume is less than about 12,000 Btu/cu.ft. hr. The combustion gases pass from the main chamber into a first reburn stage. The throat between the two sections introduces the gas into the latter at an angle of about 60.degree. relative to the direction of travel in the reburn section.