Low velocity burner for thermal expansion of particulate solids

Claim 1

A burner apparatus with a low flame velocity, for use with a furnace for expanding particulate solids, the furnace having an expansion chamber with a flat top, and the burner apparatus being defined by: a. a burner pot which is mounted on the flat top of the furnace expansion chamber, and which includes an upper compartment, a lower compartment, and a peripheral compartment; and wherein b. the upper compartment has an upper wall which includes an inlet in communication with a mixing apparatus, for introducing a pre-mixed fuel gas and air mixture into the said upper compartment; c. the peripheral compartment surrounds the upper and lower compartments and is separated therefrom by a common side wall, the peripheral compartment also having an outer wall which includes an inlet in communication with an auxiliary air supply line; d. the lower compartment is positioned directly below the upper compartment and is separated therefrom by a first horizontal plate member; e. several spaced apart ports are positioned in the common side wall separating the lower compartment and the peripheral compartment, for directing the auxiliary air supply from the peripheral compartment into the lower compartment; f. feed nozzle means are defined by tubular members disposed vertically within and extending the full length of the upper and lower compartments, for directing particulate solids downwardly into the furnace expansion chamber; g. flame nozzle means defined by tubular members which are attached to the horizontal plate member, which extend vertically downwardly froM the plate for the full length of the lower compartment, and which are positioned adjacent to the feed nozzle members, for directing a flame into the furnace chamber, and h. a second plate member which is positioned horizontally in the lower compartment below the auxiliary air ports and which has holes therein defining annular spaces around the flame nozzles, for directing the auxiliary air downwardly around the flames issuing from the flame nozzles.