Selective catalytic reduction refers to the use of reducing agents (such as ammonia, liquid ammonia, urea, etc. ) reacts selectively with nitrogen oxides in flue gas to generate non-toxic and pollution-free nitrogen and water under the action of catalyst. This method was first discovered by engelhard Company in the United States and applied for a patent in 1957. Later, under the impetus of the national environmental protection policy, Japan successfully developed the catalyst widely used today, and successfully put it into commercial use in oil-fired boilers and coal-fired boilers on 1977 and 1979 respectively. Selective catalytic reduction method is very effective and mature in controlling nitrogen oxides in boiler flue gas. At present, it has become the most widely used and effective flue gas denitrification technology in the world.
Features: 1, high removal efficiency of nitrogen-containing chemicals;
2, the secondary pollution is small;
3. Mature technology;
4. High investment cost and high operation cost.