Uneven distribution of pulverized coal in each pulverized coal tube at outlet of the pulverizer of opposedfired once through boiler makes the combustion intensity of the same layer burners deviate in the width direction of the furnace

which is easy to cause wall temperature deviation

leading to steam temperature limitation and tube burst due to wall temperature over temperature or stress concentration. By taking a typical ultra supercritical 3 000 t/h opposed-fired once through boiler as an example

the variation law of the maximum deviation of water wall temperature in the process of boiler start-up was experimentally studied

the influences of coal quality

operation mode of coal mill and air distribution mode on the distribution of wall temperature at low load were investigated. It was pointed out that

the main reason for the large deviation of water wall temperature during deep peak shaving of the once through boiler was excessive deviation of coal powder distribution in each pulverized coal tube at the outlet of the pulverizer. In this regard

the treatment plan of adding pulverized coal distributor at the outlet of coal mill was put forward. After the implementation

the distribution deviation of pulverized coal was reduced to ±10%

and the operation safety

economy and deep peak shaving capacity of the boiler was improved.