Here is an assembly for purification of process air. The air is subjected to high temperatures which ignite and destroy flammable particles. A horizontal heat exchanger filled with incoming process air is heated by the outgoing purified air. The top tank is an oxidizer dwelling chamber with a natural gas burner to ignite and assist in the self-destruction process. Due to the, high temperatures involved both vessels are internally insulated. The purified and unpurified air are separated by a novel design that allows for the thermal expansion of the tubes. All-Weld can fabricate to any specified diameter and length, and has shipped these products to the USA, Canada, and Europe. The majority of these heat exchangers are manufactured from carbon steel with internal ceramic insulation, however in some cases stainless steel or high nickels with external insulation are utilized instead.