Energy efficient pollution abating glass manufacturing process with external recovery of heat from furnace flue gases

Claim 3

The method of claim 1 and further including beneficially utilizing said recovered heat.

Claim 4

A glass manufacturing process comprising combining water and particulate, glass-forming materials into agglomerates for producing a glass containing less than 3 percent by weight of alkaline metal oxides, supplying said agglomerates to a first chamber unto the upper portion of a first bed of agglomerates in said chamber, supplying agglomerates from a lower portion of said first bed to a second chamber unto the upper portion of a second bed of said agglomerates in said second chamber, supplying agglomerates at an elevated temperature, but less than the sintering temperature of the agglomerates, from a lower portion of said second bed to a fossil-fuel fired glass melting furnace, introducing flue gases from said furnace into said second chamber, passing said flue gases through said second bed in direct contact with the agglomerates so as to heat said agglomerates in said second bed, removing said flue gases after passage through said second bed from said second chamber and while removed from said first and second chambers recovering heat from said removed flue gases with a heat transfer medium flowing in a heat exchanger, introducing said flue gases after heat recovery therefrom into said first chamber, passing said latter introduced flue gases through said first bed in direct contact with the agglomerates so as to remove water from the agglomerates of said first bed, removing said flue gases after passage through said first bed from said first chamber, and melting said agglomerates supplied to said furnace.

Claim 5

A glass manufacturing process comprising combining water and particulate, glass-forming materials into agglomerates for producing a glass containing less than 3 percent by weight of alkaline metal oxides, supplying said agglomerates to a first chamber unto the upper portion of a first bed of agglomerates in said chamber, supplying agglomerates from a lower portion of said first bed to a second chamber unto the upper portion of a second bed of said agglomerates in said second chamber, supplying agglomerates at an elevated temperature, but less than the sintering temperature of the agglomerates, from a lower portion of said second bed to a fossil-fuel fired glass melting furnace, introducing flue gases from said furnace into said second chamber, passing said flue gases through said second bed in direct contact with the agglomerates so as to heat said agglomerates in said second bed, removing said flue gases after passage through said second bed from said second chamber and while removed from said first and second chambers recovering heat from said removed flue gases with a heat transfer medium flowing in a heat exchanger, introducing said flue gases after heat recovery therefrom into said first chamber, passing said latter introduced flue gases through said first bed in direct contact with the agglomerates so as to remove water from the agglomerates of said first bed, removing said flue gases after passage through said first bed from said first chamber, and melting said agglomerates supplied to said furnace.

Claim 6

The process of claim 3 wherein said heat is recovered in a heat exchanger by air.

Claim 7

In a method of manufacturing glass comprising: providing water containing agglomerates of glass batch for producing a glass containing less than about 3 percent by weight of alkaline metal oxides, heating said agglomerates by direct contact with flue gases so as to dry them and raise their temperature, said heating being insufficient, however, to cause said agglomerates to aggregate and melting said heated agglomerates, the improvement wherein said heating is done in at least two stages, said flue gases being withdrawn from one stage, heat recovered therefrom in an external heat exchanger and then introduced to the other stage.

Claim 8

In a method of manufacturing glass comprising: providing water containing agglomerates of glass batch for producing a glass containing less than about 3 percent by weight of alkaline metal oxides, heating said agglomerates by direct contact with flue gases so as to dry them and raise their temperature, said heating being insufficient, however, to cause said agglomerates to aggregate and melting said heated agglomerates, the improvement wherein said heating is done in at least two stages, said flue gases being withdrawn from one stage, heat recovered therefrom in an external heat exchanger and then introduced to the other stage.

Claim 9

An energy-efficient, pollution-abating glass manufacturing apparatus comprising: a combustion-heated glass melting furnace, means for converting particulate glass batch into agglomerates, first and second chamber means each adapted to contain a bed of agglomerates and to heat same by direct contact with combustion gases, means supplying agglomerates from said converting means to said first chamber, means discharging agglomerates from said first chamber to said second chamber, means directing combustion gases from said furnace to said second chamber, heat exchange means disposed outwardly of said chambers for recovering heat from said combustion gases, duct means directing combustion gases from said second chamber to said heat exchange means, duct means directing combustion gases from said heat exchange means to said first chamber, and means supplying heated agglomerates from said second chamber to said furnace.

Claim 10

An energy-efficient, pollution-abating glass manufacturing apparatus comprising: a combustion-heated glass melting furnace, means for converting particulate glass batch into agglomerates, first and second chamber means each adapted to contain a bed of agglomerates and to heat same by direct contact with combustion gases, means supplying agglomerates from said converting means to said first chamber, means discharging agglomerates from said first chamber to said second chamber, means directing combustion gases from said furnace to said second chamber, heat exchange means disposed outwardly of said chambers for recovering heat from said combustion gases, duct means directing combustion gases from said second chamber to said heat exchange means, duct means directing combustion gases from said heat exchange means to said first chamber, and means supplying heated agglomerates from said second chamber to said furnace.