Improvements in heat recovering apparatus for evaporators

摘要

A device for the recovery of waste heat from evaporators is interposed between the evaporator and the discharge chimney for the vapours and comprises a central passage, heat-exchange means arranged between the passage and the external wall of the device, and a baffle fitted with a valve at the end of the passage which permits either the deflection of the vapours through the heat-exchange means or the direct discharge of the vapours from the end of the passage. The vapours may contain air. The heat-exchange means may be coils, bundles of tubes or any other type of surface exchanger, or may be a water-atomizing device. In Fig. 1, the vapours from evaporator a pass through central passage c which is capped by frustocone d provided with valve e. The frustocone extends downwards as a cylindrical wall f which divides the space between the central passage and the external wall b into annular spaces f1 and f2 in which worms g and h are housed. Water enters the worms at i, and leaves at j. If valve e is open, the vapours pass out directly and there is no heat recovery. But if valve e is closed, the vapours pass through the annular spaces and heat the water in the worms. A condensate is formed which is withdrawn through pipe k. Uncondensed vapour is discharged by means of fan v. In Fig. 4, water is atomized directly into the device through perforated tubes q and r. The hot water mixed with the condensate is removed through pipe k. The Specification as open to inspection under Sect. 91 describes modified devices such as that shown in Fig. 5 (Cancelled), wherein baffles s and t replace the central flue and frustocone described above. The condensate is withdrawn through pipe u. This subject-matter does not appear in the Specification as accepted.