Reheat boiler

Abstract

Provided is a reheat boiler in which the imbalance in temperature distribution of the temperature of the combustion gas at the outlet of a reheat furnace is reduced by changing the gas flow pattern in the reheat burner. A reheat boiler includes a main boiler configured such that main combustion gas generated in combustion in a burner flows from a furnace through a superheater and evaporator tubes, a reheat furnace that is disposed on the downstream of the evaporator tubes and produces reheat combustion gas by combustion in a reheat burner, and a reheater disposed above the reheat furnace. A closing plate, serving as a drift preventing portion, is provided at a reheat furnace outlet that connects the reheat furnace and the reheater to form a flow path for the combustion gas and the reheat combustion gas so as to narrow the cross-sectional area of the flow path for the combustion gas.

1 . A reheat boiler comprising: a main boiler configured such that main combustion gas generated by combustion in a burner flows from a furnace through a superheater and evaporator tubes; a reheat furnace that is disposed on the downstream of the evaporator tubes and produces reheat combustion gas by combustion in a reheat burner; and a reheater disposed above the reheat furnace,
 wherein a drift preventing portion that narrows the cross-sectional area of a flow path for the combustion gas is provided at a reheat furnace outlet connecting the reheat furnace and the reheater and forming the flow path for the combustion gas and the reheat combustion gas.   
     
     
         2 . The reheat boiler according to  claim 1 , wherein the drift preventing portion is formed by attaching a closing plate to the outlet of the reheat furnace. 
     
     
         3 . The reheat boiler according to  claim 2 , wherein the closing plate can be divided into a plurality of segments such that the segments can be independently attached or removed.