SCR dilution air fan

Application

Selective catalytic reduction (SCR) is a process to reduce nitrogen oxide by ammonia in thermal power plant. Before entering ammonia injection grid, ammonia is mixed sufficiently with dilution air in static mixer, which helps to adjust ammonia concentration and get even ammonia distribution into furnace through AIG.

Dilution air blower, normally a high pressure centrifugal blower, supplies enough air to mix with vaporized ammonia, which is diluted to lower than 5% by volume to prevent explosion.

Each power generation unit should be equipped with at least 2 dilution air blowers. One in operation, one as standby.

Function

• Keep ammonia concentraction below explosion limit.
• Serve as ammonia carrier to blow it into furnace.
• Dilution air is heated before mixing. Hot air helps to vaporize water contained in ammonia.