Exhaust gas heat recovery device and exhaust gas treatment system using the same

摘要

PROBLEM TO BE SOLVED: To efficiently recover heat from exhaust gas and to perform an exhaust gas treatment corresponding to a dew point of the exhaust gas.SOLUTION: A heat recovery device for exhaust gas uses a single end double tube-type ceramics tube mainly composed of SiC and closed at one end, including a heat exchange portion 1 having a flow channel in which a liquid heat medium M can be circulated, inside of the ceramics tube, is disposed in a circulation passage for exhaust gas G of a heat resisting temperature of the ceramics tube or less, recovers hot heat of the exhaust gas G through the heat medium M heated by heat exchange with the exhaust gas G, and determines the temperature and a flow rate of the heat medium M so that a low temperature region in which a temperature of a part of a ceramics tube surface becomes a dew point of the exhaust gas G or less, and a high temperature region which is close to the low temperature region and in which the temperature becomes the dew point or more are formed, on the basis of a moisture content of the exhaust gas introduced into the circulation passage or the dew point of the exhaust gas, and the temperature of the fed-out exhaust gas is the dew point of the exhaust gas or more.SELECTED DRAWING: Figure 1