Heat-exchanger system

Claim 2

A heat exchange system comprising a plurality of heat exchangers each containing therein a regenerative heat accumulating medium capable of alternately storing and releasing heat energy; a plurality of air preheaters each containing therein a regenerative heat accumulating medium capable of alternately storing and releasing heat energy; a burner connected to each said heat exchanger receptive of both a fuel and combustion air to burn same and evolve an exhaust gas; means for flowing the exhaust gas from each burner serially through the associated heat exchanger and one of said air preheaters whereby the regenerative heat accumulating mediums contained within that heat exchanger and air preheater absorbs and stores heat energy from the exhaust gas; fluid supply means for supplying fluid to be heated through only those heat exchangers containing therein a heat accumulating medium possessing stored heat energy whereby the heat accumulating medium releases its heat energy to the fluid to heat same; and combustion air supply means for serially supplying combustion air through only those air preheaters containing therein a heat accumulating medium possessing stored heat energy to effect preheating of the combustion air and then to only those burners connected to a heat exchanger containing therein a heat accumulating medium ready to be supplied with heat energy whereby preheated combustion air is supplied to the burners.

Claim 3

A heat exchange system according to claim 1; wherein said means for flowing the exhaust gas includes a conduit connecting each heat exchanger with one air preheater, a flow control valve disposed within said conduit operable to control the fluid flow therethrough; and wherein said fluid supply means includes another conduit connected to each said first-mentioned conduit upstream from said flow control valve, and another flow control valve disposed within said another conduit operable to control the fluid flow therethrough; whereby said flow control valves may be alternately operated to control the flow of exhaust gas and the fluid to be heated through each heat exchanger.

Claim 4

A heat exchange system according to claim 1; wherein said combustion air supply means includes a conduit connecting each air preheater to a burner connected to a heat exchanger which is different than that which supplies exhaust gas to that air preheater.

Claim 5

A heat exchanger system comprising, in combination: a plurality of regenerative heat exchangers each having a low temperature side inlet receptive of a fluid to be heated, a high temperature side outlet for discharging the heat-exchanged fluid, and containing therein a heat accumulating medium capable of storing and releasing heat to heat the fluid, said low temperature side inlet also serving as an outlet for exhaust gas; heating means provided on each of said regenerative heat exchangers to heat the heat accumulating medium contained therein; fuel supply means including supply tubes and flow control valves to supply fuel to each of said heating means through said supply tubes and flow control valves; a plurality of air preheaters each connected to each of said heat exchangers and containing therein a heat accumulating medium capable of absorbing and storing heat from the exhaust gas introduced from each said heat exchanger, each air preheater having an exhaust gas inlet for receiving the exhaust gas from the corresponding heat exchanger, a combustion air inlet for receiving the combustion air, a combustion air outlet for discharging the preheated combustion air and an exhaust gas outlet for discharging the exhaust gas; a tube and a flow control valve connecting each said exhaust gas inlet to the exhaust gas outlet of a corresponding heat exchanger; means including a supply tube and flow control valve for supplying the fluid to be heated to the low temperature side inlet of each heat exchanger and intersecting a connecting tube extending between the exhaust gas outlet of the heat exchanger and the exhaust gas inleT of the air preheater; means including additional supply tubes and flow control valves for supplying the combustion air to said combustion air inlet of each of said preheaters; and means including connecting tubes connecting the outlet for the preheated combustion air of the one preheater for one heat exchanger to the heating means for another heat exchanger to supply the combustion air heated in the preheaters by the exhaust gas generated in the heating means and sent from the heat exchangers with the heating means by change over operation of the flow control valves.

Claim 6

A heat exchanger system comprising, in combination: a plurality of regenerative heat exchangers each having a low temperature side inlet receptive of a fluid to be heated, a high temperature side outlet for discharging the heat-exchanged fluid, and containing therein a heat accumulating medium capable of storing and releasing heat to heat the fluid, said low temperature side inlet also serving as an outlet for exhaust gas; heating means provided on each of said regenerative heat exchangers to heat the heat accumulating medium contained therein; fuel supply means including supply tubes and flow control valves to supply fuel to each of said heating means through said supply tubes and flow control valves; a plurality of air preheaters each connected to each of said heat exchangers and containing therein a heat accumulating medium capable of absorbing and storing heat from the exhaust gas introduced from each said heat exchanger, each air preheater having an exhaust gas inlet for receiving the exhaust gas from the corresponding heat exchanger, a combustion air inlet for receiving the combustion air, a combustion air outlet for discharging the preheated combustion air and an exhaust gas outlet for discharging the exhaust gas; a tube and a flow control valve connecting each said exhaust gas inlet to the exhaust gas outlet of a corresponding heat exchanger; means including a supply tube and flow control valve for supplying the fluid to be heated to the low temperature side inlet of each heat exchanger and intersecting a connecting tube extending between the exhaust gas outlet of the heat exchanger and the exhaust gas inleT of the air preheater; means including additional supply tubes and flow control valves for supplying the combustion air to said combustion air inlet of each of said preheaters; and means including connecting tubes connecting the outlet for the preheated combustion air of the one preheater for one heat exchanger to the heating means for another heat exchanger to supply the combustion air heated in the preheaters by the exhaust gas generated in the heating means and sent from the heat exchangers with the heating means by change over operation of the flow control valves.