Gas fired particulate melting apparatus and method

A liquid fuel fired furnace apparatus for melting flowable particulate material, said apparatus comprising:

• a vertically disposed hollow cylindrical shaft for preheating a foraminous column of flowable particulate feedstock, said shaft having a circular open bottom end, a concentrically aligned chamber for containing a feedstanding pile of preheated feedstock, said chamber being disposed directly below said bottom end in open communication therewith, said chamber having top, bottom and intermediate portions defined by refractory sidewalls and a refractory floor, said sidewalls having inner surfaces which extend downwardly and outwardly from said open bottom end to said floor, a first fuel combustion system having a heat exchanger for producing heated air and cooled combustion gases, a second combustion system having a plurality of high temperature burners firing into the intermediate and bottom portions of said chamber, a means for conveying said heated air under pressure from said first system to the burners of said second system, and means for conveying said cooled combustion gases from said first system into the top of said chamber.

An improved method of melting particulate material comprising the steps of:

• introducing particulate material into the top of a vertically disposed preheater shaft, supporting said particulate material in said preheater shaft on a freestanding pile of preheated particulate material disposed on an inclined floor of a melting chamber, enveloping a top portion of said free standing pile with cooled combustion gases from a remote source, subjecting the intermediate and base portions of said pile to intense heat capable of melting the particulate material on the outside surface of said pile, allowing the melted material to gravitate to the lower end of said slope, and collecting said melted material in a reservoir at the bottom of the slope.