Efficient plate-type air preheater

Abstract

The invention discloses an efficient plate type air preheater which includes a shell, wherein a high-temperature air heat exchange section and a low-temperature air heat exchange section are arrangedin the shell. The high-temperature air heat exchange section is provided with an air inlet and a smoke inlet; the low-temperature air heat exchange section is provided with an air outlet and a smoke outlet; the high-temperature air heat exchange section and the low-temperature air heat exchange section are in butt joint through an air transition channel. The high-temperature air heat exchange section and the low-temperature air heat exchange section are plate type heat exchange sections and are composed of a plurality of heat exchange plates, air flow channels for air circulation and smoke flow channels for smoke circulation are formed between the heat exchange plates, the air flow channels and the smoke flow channels are not communicated with each other, and the heat exchange plates are of an S-shaped structure overall.

Description

technical field [0001] The invention relates to a plate-type air preheater, in particular to a high-efficiency plate-type air preheater for heating furnaces in hot rolling mills in the iron and steel industry. Background technique [0002] The tube-and-tube air preheater generally used in the heating furnace of the hot rolling mill, due to dust accumulation and other reasons, the heat transfer performance will be seriously reduced within one or two years, resulting in an increase in the energy consumption of the heating furnace; It is necessary to turn on the dilution fan and mix the high-temperature flue gas with cold air to cool down the operation. The residual heat of the flue gas is not recovered well, and a lot of heat is wasted; under high-temperature conditions, the service life of carbon steel pipes is generally short, and the equipment leaks, requiring shutdown for maintenance, which affects Production. [0003] Compared with the tube-and-tube air preheater, the pl...

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Problems solved by technology

[0004] Although there is currently a Chinese patent authorization announcement number CN203731471U disclosing a split-flow plate-type air preheater, the plates of the air preheater are flat plate structures, and the heat exchange plates are places where intense heat exchange occurs between cold and hot fluids. , the local temperature difference on both sides of the plate can reach more than 600°C, and the thermal stress is huge. If the heat exchange plate adopts a large flat plate structure, the direction of expansion stress after heating will be scattered and disorderly, which will easily cause cracks on the plate surface and weld seam. The structural design will release the stress

Therefore, the service life of the heat exchange plates of the flat structure is relatively short.

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