Multi-variant phase change waste heat boiler system

Abstract

The invention relates to a multi-variant phase change waste heat boiler system which comprises an induced draft fan, a soft water preheating section, a deaerator, a saturated steam section and a superheated steam section. The soft water preheating section is composed of a tube type heat exchanger, a sleeve type heat exchanger and a low-temperature phase change heat exchanger, a steam inlet in an outer tube of the sleeve type heat exchanger is communicated with an upper collecting tank of the low-temperature phase change heat exchanger, a steam outlet in the outer tube of the sleeve type heat exchanger is communicated with a steam inlet of the tube type heat exchanger through an ascending tube, a condensate outlet of the tube type heat exchanger is communicated with a condensate inlet in an inner tube of the sleeve type heat exchanger through a descending tube, and a condensate outlet in the inner tube of the sleeve type heat exchanger is communicated with a lower collecting tank of the low-temperature phase change heat exchanger. A preheating water outlet of the tube type heat exchanger is communicated with the deaerator, the deaerator is communicated with the saturated steam section, and a steam output tube of the saturated steam section is connected with the superheated steam section in parallel. The multi-variant phase change waste heat boiler system solves the problems of oxygen corrosion and low-temperature acid dew corrosion on a waste heat boiler, the steam generation amount is large, and operation and maintenance are easily achieved.

Description

technical field [0001] The invention relates to a waste heat recovery technology of an industrial kiln, in particular to a multi-element phase change waste heat boiler system. Background technique [0002] Generally, the preheating water part of waste heat recovery boiler adopts economizer or heat pipe heat exchanger. The economizer and heat pipe heat exchanger can only increase the minimum wall temperature of the heat exchanger by increasing the inlet water temperature. If the inlet water temperature is normal temperature When the minimum wall temperature of the heat exchanger is lower than the acid dew point of the flue gas, the flue gas will condense on the surface of the heat exchanger, causing problems such as acid dew corrosion and dust accumulation on the heat exchanger, resulting in the failure of the waste heat boiler to operate normally. To maintain the economizer or the heat pipe heat exchanger, the operation and maintenance workload is heavy, and the production c...

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Problems solved by technology

[0002] Generally, the preheating water part of waste heat recovery boiler adopts economizer or heat pipe heat exchanger. The economizer and heat pipe heat exchanger can only increase the minimum wall temperature of the heat exchanger by increasing the inlet water temperature. If the inlet water temperature is normal temperature When the minimum wall temperature of the heat exchanger is lower than the acid dew point of the flue gas, the flue gas will condense on the surface of the heat exchanger, causing problems such as acid dew corrosion and dust accumulation on the heat exchanger, resulting in the failure of the waste heat boiler to operate normally. To maintain the economizer or heat pipe heat exchanger, the workload of operation and maintenance is heavy, and the production cost is increased

In order to avoid acid dew corrosion, economizers and heat pipe heat exchangers often adopt the method of increasing the exhaust gas temperature, which causes a large waste of flue gas heat

[0003] The invention patent with the patent number CN201120443051.3 discloses a composite phase change heat exchanger for boiler flue gas waste heat recovery. A thermostat is used to adjust the temperature of the phase change working medium according to the change of the acid dew point of the flue gas, and then control the phase change The temperature of the wall surface of the heat exchanger can avoid low-temperature corrosion of the flue gas, and the boiler system has a complex structure and is not easy to operate

[0004] In addition, the existing waste heat recovery boilers either produce saturated steam or superheated steam. In a set of equipment, users cannot choose to produce saturated steam or superheated steam according to actual needs.

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