Non-polluting hot gas generating system

Non-environmentally polluting hot gas generating system, emitting clean, non-polluting exhaust gases, comprising

• a hot gas generating chamber (2) and an after-burner chamber (3) forming, together, a combustion chamber;
• a burner means (5) emitting a fuel jet (36) located in said hot gas generating chamber and ejecting a flame jet into the chamber in a predetermined direction;
• a processing chamber (1) for carrying out thermal treatment of processes during which polluting matter including at least one of:
• combustible or oxidizable gases, combustible or oxidizable vapors, or combustible or oxidizable particles are liberated;
• a hot gas outlet (7) from the gas generating chamber (2) and coupled to the processing chamber (1) to provide hot gases therefor,
• said hot gases being cooled while carrying out said thermal treatment and liberating polluting matter;
• a hot gas recirculating inlet (8) into the gas generating chamber and coupled to the processing chamber to receive said cooled hot gases, together with liberated polluting matter, said cooled hot gases together with the liberated polluting matter and the hot gases generated by the burner mixing in a hot gas generating chamber (2) and forming a raw gas (R),
• a portion of said hot gas generating chamber, said hot gas outlet (7), a portion of the processing chamber (1) and the recirculating inlet into the hot gas generating chamber forming a closed gas cycling loop (9) in which a predetermined quantity of gases circulates;
• burner control means (14) controlling fuel supply to the burner to furnish said hot gases for said thermal treatment and energizing the gases in the hot gas generating chamber for circulation in said gas circulating loop (9);
• said after-burner chamber (3) communicating with the hot gas generating chamber (2),
• said after-burner chamber (3) defining a volume which is large enough to provide for a dwell time in said afterburner chamber of the raw gas supplied thereto from the hot gas generating chamber (2) to completely burn or oxidize said polluting matter to result in a non-polluting gas (A);
• a heat exchanger (6) coupled to receive the nonpolluting gas (A) from said after-burner chamber, said heat exchanger having an air heat exchange inlet (L) for admitting ambient air and heating said ambient air by removing heat from the non-polluting gases and said air thereby becoming preheated;
• means (17) for coupling the preheated air from the heat exchanger to the burner means (5) to thereby supply preheated combustion air thereto;
• sensing means (12) sensing at least the temperature of the raw gases (R) in the combustion chamber (2);
• and
• control means (11, 13) responsive to the sensed temperature of the raw gases (R) and maintaining the temperature of the raw gases (R) entering the after-burner chamber (3) from the combustion chamber (2) at a predetermined command level which is sufficiently high to effect complete combustion of the raw gases (R) and result in said non-polluting gas (A).