Incinerator with two reburn stages, and, optionally, heat recovery

A fume burning system for improving the environmental quality of a gaseous fluid emanating from the output of a source and containing combustible hydrocarbons with an average number of Btu's per hour comprising:

• (A) a first reburn chamber having:
• (1) a first inlet opening coupled to and in fluid communication with said output, said first inlet opening having a sufficient cross-sectional area to maintain the heat throughput through said first inlet opening to a level no greater than about 15,000 Btu/sq. ft. hr.;
• (2) a first outlet opening for the egress of the gaseous products of combustion from said first chamber;
• (3) burner means, located in proximity to said first outlet, for burning a fuel in said first chamber, said burner means having a high and a low setting and, when in its high setting, burning more fuel than when in its low setting;
• (4) a first plurality of jets extending into said first reburn chamber, said jets extending at least about half of the distance from said first inlet opening to said first outlet opening;
• (5) first oxygenating means, coupled to said first plurality of jets, for introducing an oxygen-containing gas through said first plurality of jets into said first reburn chamber, said first oxygenating means having a high and a low setting and, when in its high setting, introducing a greater volume of a gas through said first plurality of jets than when in its low setting;
• (B) a second reburn chamber having:
• (1) a second inlet opening coupled to and in fluid communication with said first outlet opening;
• (2) a second outlet opening for the egress of the gaseous products of combustion from said second chamber;
• (3) a second plurality of jets extending into said second reburn chamber, said jets extending at least about half of the distance from said second inlet opening to said second outlet opening;
• and
• (4) second oxygenating means, coupled to said second plurality of jets, for introducing an oxygen-containing gas through said second plurality of jets into said second reburn chamber, said second oxygenating means having a high and a low setting and, when its high setting, introducing a greater volume of gas through said second plurality of jets than when in its low setting;
• (C) first sensing means, located in proximity to said first reburn chamber, for determining a temperature within said first reburn chamber;
• (D) first control means, coupled to said first oxygenating means and to said first sensing means, for, when the temperature determined by said first sensing means is above a first predetermined set point, placing said first oxygenating means in its high setting and, when the temperature determined by said first sensing means is below said first set point, placing said first oxygenating means in its low setting;
• (E) second sensing means, located in proximity to said first reburn chamber, for determining a temperature within said first reburn chamber;
• (F) second control means, coupled to said burner meand and to said second sensing means, for, when the temperature determined by said second sensing means is above a second predetermined set point, placing said burner means in its low setting and, when the temperature determined by said second sensing means is below a third predetermined set point which is not higher than said second set point, placing said burner means in its high setting;
• (G) third sensing means, located in proximity to said second reburn chamber, for determining a temperature within said second reburn chamber;
• and
• (H) third control means, coupled to said third sensing means and to said second oxygenating means, for, when the temperature determined by said third sensing means is above a fourth predetermined set point, placing said second oxygenating means in its high setting and, when the temperature determined by said third sensing is below said fourth set point, placing said oxygenating means in its low setting.

In a combustion chamber for bulk refuse and hydrocarbon-containing liquids having:

• (a) four substantially fire-resistant walls connected together with first and second pairs of said walls facing each other;
• (b) a substantially fire-resistant roof connected to said walls;
• (c) a fire-resistant floor coupled to all of said walls:
• (d) an inlet opening formed in one of said walls of said first pair for the introduction of refuse;
• (e) an outlet opening formed in said roof for the egress of the gaseous products of combustion from said second chamber;
• and
• (f) oxygenating means for introducing an oxygen-containing gas into said chamber,
• the improvement wherein said floor comprises a fire-resistant hearth floor capable of supporting bulk refuse placed in said chamber through said inlet opening, said floor including (a) vertical steps aligned parallel to said second pair of walls with a first plurality of the faces of said steps facing one of the walls of said second pair and a second plurality of the faces of said steps facing the other of the walls of said second pair;
• (b) substantially horizontal flat planes interconnecting adjacent steps;
• and (c) a plurality of nozzles coupled to said oxygenating means, located in each of said vertical steps, and extending substantially the entire distance between the walls of said first pair, said oxygen-containing gas passing through said nozzles immediately prior to entering said combustion chamber.

In a combustion chamber for burning bulk refuse and hydrocarbon-containing liquids at an average predetermined rate of But's per hour, said chamber having:

• (a) four substantially fire-resistant walls connected together, with first and second pairs of said walls facing each other;
• (b) a substantially fire-resistant roof connected to said walls;
• (c) a fire-resistant hearth floor coupled to all of said walls;
• (d) an inlet opening formed in one of said walls of said first pair for the introduction of refuse;
• (e) an outlet opening formed in said roof for the egress of the gaseous products of combustion from said chamber;
• and
• (f) oxygenating means for introducing an oxygen-containing gas into said chamber,
• the improvement wherein:
• (A) said oxygenating means introduces said gas in amounts to provide within said chamber an amount of oxygen equal to about 90 to 110 percent of stoichiometric for burning within said chamber refuse having about said average predetermined rate of Btu's;
• (B) said floor has a horizontal area surrounded by said walls such that the area ratio of said average predetermined rate of Btu./hr. to said area is within the range of about 75,000 to 135,000 Btu./sq.ft. hr.;
• and
• (C) said chamber has a volume between said walls, roof, and floor such that the volume ratio of said average predetermined rate of Btu per hour to said volume is within the range of about 7,000 to 15,000 Btu./cu.ft.hr.

In a combustion chamber for burning bulk refuse and hydrocarbon-containing liquids at an average predetermined rate of Btu. per hour, said chamber having:

• (a) four substantially fire-resistant walls connected together, with first and second pairs of said walls facing each other;
• (b) a substantially fire-resistant roof connected to said walls;
• (c) a fire-resistant hearth floor coupled to all of said walls;
• (d) an inlet opening formed in one of said walls of said first pair for the introduction of refuse;
• (e) an outlet opening formed in said roof for the egress of the gaseous products of combustion from said chamber;
• and
• (f) a plurality of nozzles located in said floor through which a gas can flow into said chamber and extending substantially all of the distance between said first pair of walls,
• the improvement comprising oxygenating means for:
• (A) introducing an oxygen-containing gas through said nozzles into said chamber, in amounts to provide within said chamber an amount of said oxygen equal to about 90 to 110 percent of stoichiometric for burning within said chamber refuse having about said average predetermined rate of Btu.;
• and
• (B) passing said gas out of said nozzles with a velocity of less than about 300 ft./min.

In a combustion chamber for bulk refuse and hydrocarbon-containing liquids having:

• (a) four substantially fire-resistant walls connected together, with first and second pairs of said walls facing each other;
• (b) a substantially fire-resistant roof connected to said walls;
• (c) a fire-resistant floor coupled to all of said walls;
• (d) an inlet opening formed in one of said walls of said first pair for the introduction of refuse;
• and
• (e) an outlet opening formed in said roof for the egress of the gaseous products of combustion from said chamber;
• the improvement wherein:
• (A) the walls of said first pair are substantially parallel to each other, the walls of said second pair are substantially parallel to each other, and said chamber has a substantially rectangular shape on cross-sectional planes taken parallel to said walls of said first pair;
• and
• (B) said one wall of said first pair and said walls of said second pair have substantially the same height and the ratios of said height on the length of the walls of said first pair to the length of the walls of said second pair fall within the range or about 1:0.9:2 to 1:1.1:3.5.

An incinerator system for bulk refuse and hydrocarbon-containing liquids comprising:

• (A) a main combustion chamber having:
• (1) a first inlet opening for the introduction of solid bulk refuse;
• (2) a first outlet opening for the egress of the gaseous products of combustion from said main combustion chamber;
• and
• (3) first exchange means for removing heat from said main chamber in a form useful elsewhere, said exchange means including:
• (a) a heat exchanger conduit in said main chamber for carrying a heat exchange fluid through said main chamber;
• (b) inlet means for introducing a heat exchange fluid into said heat exchanger conduit;
• and
• (c) outlet means for permitting the egress of said heat exchanger fluid from said heat exchanger conduit;
• (B) a reburn unit having:
• (1) a second inlet opening coupled to and in fluid communication with said first outlet opening;
• (2) a second outlet opening for the egress of the gaseous products of combustion from said reburn unit;
• (3) burner means, coupled to said unit, for burning a fuel in said reburn unit;
• (4) oxygenating means, coupled to said reburn unit, for introducing an oxygen-containing gas into said reburn unit;
• and
• (5) insulating means for preventing the escape of substantial heat from said reburn unit except through said second outlet opening;
• and
• (C) a recovery unit having:
• (1) a third inlet opening coupled to and in fluid communication with said second outlet opening;
• (2) a third outlet opening for the egress of the gaseous products of combustion from said recovery unit;
• and
• (3) second exchange means for removing heat from said recovery unit in a form useful elsewhere.