GB603874A - Improvements in or relating to plant for the recovery of waste heat from furnace gases - Google Patents

Abstract

603,874. Turbines. SPENCER-BONECOURT, Ltd., and GREGSON, W. Nov. 2, 1945, No. 29124. [Class 110 (iii)] In a plant for the recovery of waste heat from an industrial furnace comprising a heat exchanger, draught-inducing means draws the waste gases through the heat exchanger, and a compressor delivers working fluid to a turbine by way of the heat exchanger ; means are provided for supplying a controlled amount of additional heat to the working fluid. The waste gases from the furnace 2, Fig. 2, are drawn through the heat exchanger 3 by means of a fan 1. The compressor 4, comprising stages 4<1>, 4<11>, with an intercooler 10, delivers air by way of a heat exchanger element 3<1> to a turbine 5. The latter comprises stages 51, 5<11> with an interstage heater 3<11> forming part of the heat exchanger 3. Cooling water from the intercooler 10 is fed to a boiler 9 where it is heated by the turbine exhaust to produce steam or hot water. Additional heat is supplied to the heat exchanger 3 by an auxiliary combustion chamber 6, the firing of which is controlled automatically to regulate the turbine output. The control means may be responsive to variations in turbine speed from a normal value. The gases from the auxiliary combustion chamber may now through a separate section of the heat exchanger 3 or through a separate heat exchanger. In the embodiment shown in Fig. 3, the turbine exhaust passes through an auxiliary heat exchanger 12, and the boiler 9 is heated by the waste gases from the furnace. In a further embodiment the turbine exhaust and the furnace gases are passed through separate sections of the boiler 9.