Incineration of persistent organic pollutants (POPs) is an important alternative way for disposal of this type of hazardous waste. PCBs are very stable compounds and do not decompose readily. Individuals can be exposed to PCBs through several ways and damaged by their effects. A well design of a waste incinerator will convert these components to unharmfull materials. In this paper we have studied the design parameters of an incinerator with numerical approaches. The CFD software Fluent 6.3 is used for modelling of an incinerator. The effects of several baffles inside the incinerator on flow distribution and heat is investigated. The results show that baffles can reduce eddy flows, increase retaining times, and efficiencies. The baffles reduced cool areas and increased efficiencies of heat as maximum temperature in two and three baffle embedded incinerator were 100 and 200 °C higher than the non-baffle case, respectively. Also the gas emission leaves the incinerator with a lower speed across a longer path and the turbulent flow in the incinerator is stronger.