Perlite expansion process and apparatus therefor
AssigneeJohns Manville
InventorAndre R. de Muinck
Life of this patent
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Abstract
A process and apparatus therefor are described for the expansion of perlite utilizing vaporized heavy liquid fuel as at least half, and preferably all, of the combustion fuel. In this process preheated air is used to vaporize the liquid fuel, which has previously been atomized.
Claims14
In a process for the expansion of perlite in which perlite granules are expanded by rapid heating in a flame zone in an expansion chamber, said flame zone is created by the combustion of combustible fuel in the presence of air, said combustion is initiated by a burner, and said perlite after expansion is conveyed out of said expansion chamber entrained in the flow stream formed of excess air and combustion products, the improvement whereby said process may be operated on combustible fuel comprising light fuel, heavy liquid fuel or mixtures thereof alternatively, without change in the apparatus by which means the process is practiced, said improvement comprising:
- (a) preheating the air for combustion in an enclosure adjacent to the outer wall of said expansion chamber, said preheating being accomplished by contacting the air with said outer wall of said expansion chamber and absorption by said air of heat emanating from said wall;
- (b) providing a conduit for said preheated air from said enclosure to said burner;
- (c) locating a mixing chamber in said conduit at a point ahead of said burner;
- (d) passing said preheated air to said mixing zone;
- (e) providing to said mixing zone a quantity of combustion fuel sufficient to burn in the presence of said preheated air in said expansion chamber to form said flame zone, the combustion fuel and preheated air being mixed in said mixing zone;
- (f) atomizing the heavy liquid fuel component of said combustion fuel and passing said mixed combustion fuel and air to a vaporization zone;
- (g) vaporizing said atomized heavy liquid fuel component and the liquid fuel component of the light fuel component of said combustion fuel by contact with said preheated air in said vaporization zone;
- and
- (h) passing the mixture of vaporized combustion fuel and preheated air to said burner and burning said combustion fuel in the presence of said air to form said flame zone.
Perlite expansion apparatus which can utilize vaporized heavy liquid fuel for combustion, wherein perlite granules are expanded by rapid heating in a flame zone in an expansion chamber in which air and combustible fuel generate the flame zone and in which the perlite after expansion is conveyed out of the chamber by the flow of residual air and combustion by-products, said apparatus comprising, in combination with a perlite expansion chamber having an inlet port, an outlet port, means for introducing perlite ore into the expansion chamber, and burner means for establishing a combustion flame zone in which the perlite ore is expanded in the chamber:
- (a) means for preheating the combustion air, said means comprising an enclosure surrounding at least a portion of the outer surface of the wall of the expansion chamber, such that air in the enclosure will be in contact with the outer surface of the wall and be preheated by absorption of heat emanating therefrom;
- (b) mixing means outside of said expansion chamber for mixing atomized heavy liquid fuel and preheated combustion air;
- (c) means for passing said preheated combustion air from said enclosure to said mixing means;
- (d) means for atomizing a quantity of heavy liquid fuel;
- (e) means for passing the atomized heavy liquid fuel from said atomizing means to said mixing means;
- (f) means wherein the atomized heavy liquid fuel is vaporized by contact with said preheated combustion air;
- and (g) means to pass the mixture of vaporized heavy liquid fuel and preheated combustion air to said burner, wherein said vaporized heavy liquid fuel comprises at least part of said combustible fuel.
Dependencies are inferred from the claim text.