Integrated drainable economizer with boiler bank

Claim 1

IN COMBINATION, TOP, BOTTOM AND SIDE WALLS FORMING A HORIZONTAL PASSAGEWAY THROUGH WHICH HOT COMBUSTION GASES PASS, THE PASSAGEWAY HAVING AN INLET END AND AN OUTLET END, A FIRST CYLINDRICAL DRUM LOCATED ADJACENT THE TOP WALL AND POSITIONED SUCH THAT ITS AXIS IS TRANSVERSE TO THE AXIS OF THE PASSAGEWAY, A SECOND CYLINDRICAL DRUM LOCATED ADJACENT THE BOTTOM WALL AND POSITIONED SUCH THAT ITS AXIS IS TRANSVERSE TO THE AXIS OF THE PASSAGEWAY, FIRST WALL MEANS COOPERATING WITH A PORTION OF THE FIRST DRUM WALL FOR FORMING A PLURALITY OF VERTICALLY SPACED, COMPLETELY ENCLOSED FIRST COMPARTMENTS WITHIN THE FIRST DRUM INTERIOR, SECOND WALL MEANS COOPERATING WITH A PORTION OF THE SECOND DRUM WALL FOR FORMING A PLURALITY OF VERTICALLY SPACED, COMPLETELY ENCLOSED SECOND COMPARTMENTS WITHIN THE SECOND DRUM INTERIOR, A PORTION OF THE SECOND WALL MEANS BEING REMOVABLE, SAID PORTION BEING OF SUCH A SIZE AND LOCATED SUCH THAT WHEN IT IS REMOVED ALL OF THE SECOND COMPARTMENTS ARE DRAINABLE INTO THE SECOND DRUM INTERIOR, A FEEDWATER INLET TUBE CONNECTED TO THE UPPERMOST OF THE FIRST COMPARTMENTS, A FIRST ROW OF ECONOMIZER TUBES EXTENDING FROM THE UPPERMOST FIRST COMPARTMENT TO THE LOWERMOST SECOND COMPARTMENT, A SECOND ROW OF ECONOMIZER TUBES CONNECTING THE LOWERMOST SECOND COMPARTMENT TO THE NEXT UPPERMOST FIRST COMPARTMENT, A THIRD ROW OF ECONOMIZER TUBES CONNECTING THE NEXT UPPERMOST FIRST COMPARTMENT TO THE NEXT LOWERMOST SECOND COMPARTMENT, THE REST OF THE FIRST AND SECOND COMPARTMENTS BEING LIKEWISE CONNECTED TOGETHER BY ROWS OF ECONOMIZER TUBES, AND THE UPPERMOST SECOND COMPARAMENT BEING CONNECTED WITH THE FIRST DRUM INTERIOR BY MEANS OF A LAST ROW OF ECONOMIZER TUBES, WHEREBY THE FEEDWATER FLOW SERIALLY THROUGH THE ECONOMIZER TUBES FROM THE FIRST ROW OF ECONOMIZER TUBES TO AND THROUGH THE LAST ROW OF ECONOMIZER TUBES, EACH ROW OF ECONOMIZER TUBES BEING IN SPACED ALIGNMENT IN THE GAS PASSAGEWAY, WITH THE FIRST ROW OF ECONOMIZER TUBES BEING CLOSEST TO THE PASSAGEWAY OUTLET END, AND THE LAST ROW OF ECONOMIZER TUBES BEING CLOSEST TO THE GAS PASSAGEWAY INLET, A PLURALITY OF ROWS OF BOILER TUBES EXTENDING BETWEEN THE FIRST AND SECOND DRUMS, WHICH BOILER TUBES ARE LOCATED UPSTREAM OF THE ROWS OF ECONOMIZER TUBES, IN WHICH BOILER TUBES STEAM IS GENERATED, EACH ROW OF ECONOMIZER AND BOILER TUBES CONTAINING A PLURALITY OF TUBES WHICH ARE SPACED ACROSS THE WIDTH OF THE PASSAGEWAY, AND A DISCHARGE TUBE CONNECTED TO THE UPPER PORTION OF THE FIRST DRUM, THROUGH WHICH GENERATED STEAM IS DISCHARGED.