At present

the coal-fired units use the selective catalytic reduction(SCR) technology for denitrification treatment of the flue gas to be comparatively much

but many of them are newly constructed units accompanied again with SCR denitrification facility to form a complete set under condition in which the contract of main unit having already been signed

it is inavoidably affecting the boiler.For this reason

combined with the denitrification project of 600 MW unit in one power plant

the influence of SCR denitrification facility upon tail section and air preheater of the boiler has been analysed

and problems needing attention in design and construction being pointed out.