Smoke reheating device of combining phase-change heat exchanger with net gas heater

Abstract

The invention relates to a smoke reheating device of combining a phase-change heat exchanger with a net gas heater. No smoke reheating device capable of preventing a chimney from being corroded, and emitting white smoke and misty rain, and the like exists at present. The smoke reheating device comprises a smoke flue, and a smoke thermometer, wherein the smoke reheating device is characterized by also comprising an air pre-heater, the phase-change heat exchanger, the neat gas heater, a terminal controller, a downcomer, a condensed refrigerant thermometer, a phase-change heat-exchange steam pocket, a riser pipe, a heat transfer medium thermometer, a water inlet pipe, a water return pipe, a steam inlet pipe and a steam outlet pipe; the air pre-heater, the phase-change heat exchanger and the net gas heater are arranged inside the smoke flue; one end of the water inlet pipe is fixed on the phase-change heat-exchange steam pocket; the other end is fixed on the net smoke heater; and the smoke thermometer, a steam regulating valve, a flow regulating valve, the condensed refrigerant thermometer and the heat transfer medium thermometer are electrically connected with the terminal controller. The smoke reheating device can avoid the situations that the chimney is corroded, emits white smoke and misty rain.

Description

technical field [0001] The invention relates to a flue gas reheating device, in particular to a flue gas reheating device combined with a phase change heat exchanger and a clean flue gas heater, which is mainly used for dust removal and desulfurization of flue gas produced by a thermal power plant , and reheat. Background technique [0002] Limestone wet flue gas desulfurization system (FGD) is a process developed in the 1970s. It has the characteristics of high desulfurization efficiency, good reliability and adaptability to different capacity units, so it is widely used by high-power units. At present, the domestic 300MW and above Units basically use this method to deal with boiler flue gas. It is foreseeable that for a long time to come in China, the typical limestone-gypsum wet flue gas desulfurization process will remain the mainstream process. [0003] When the limestone-gypsum desulfurization process is used, the flue gas temperature after the absorption tower or re...

AI Technical Summary

Problems solved by technology

[0004] There are deficiencies in both the installation of GGH and the non-installation of GGH. The problems caused by the installation of GGH are as follows: 1. The rotary GGH is a regenerative heat exchanger. Cold and hot fluids flow through the heat accumulator alternately, which will Cause serious air leakage, which directly affects the desulfurization efficiency; 2. Due to the working environment of GGH and its own structural defects, ash plugging, corrosion and scaling problems often occur, and the failure rate is high

The problems caused by not installing GGH are as follows: the chimney will be severely corroded, white smoke will be emitted, and the smoke and rain will be washed down.

[0005] There are also some relatively good flue gas reheating devices now. For example, in the Chinese patent whose publication date is March 28, 2007, and whose publication number is CN2883942, a separate type flue gas reheater is disclosed. The device is divided into two parts: the original flue gas heat exchanger and the clean flue gas heat exchanger. There is a large space distance between the raw flue gas side and the clean flue gas side. These two parts are connected through the steam rising pipe and the condensed water descending pipe. Although the separated flue gas reheater has the characteristics of no flue gas leakage, the overall structural design is not reasonable enough, the energy utilization rate is not high, and the heat exchange effect is not good, so it is difficult to effectively prevent the chimney from corrosion, Situations such as white smoke and smoky rain

[0006] To sum up, there is currently no flue gas reheating device with reasonable structural design, reliable performance, energy saving and environmental protection, which can effectively prevent the chimney from corrosion, white smoke, and smoke and rain washing down, etc.

Images