Abstract: A low-pollutant system for waste materials treatment includes a process chamber for converting organic components of the waste materials into a flammable gas and a two-stage vortex burning chamber for complete combustion of the flammable gas. The vortex burning chamber includes a first substantially-horizontal combustion chamber and a second substantially-vertical combustion chamber disposed at a right angle to each other and communicating therebetween. The first combustion chamber has an inlet portion for receiving the flammable combustion gas from the gas generator means for injecting primary air into the first combustion chamber, thereby forming a mixture of air and the flammable gas and thereby igniting the mixture for partial oxidation thereof.