What can be the acid concentration at the outlet of the nitric acid absorption tower in medium-pressure processes? What is the typical concentration of NOx in the flue gas at the top of the tower that can be achieved?
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What can be the acid concentration at the outlet of the nitric acid absorption tower in medium-pressure processes? What is the typical concentration of NOx in the flue gas at the top of the tower that can be achieved?
In the medium-pressure process, the concentration of acid exiting the nitric acid absorption tower can generally reach 60%-65%. The NOx concentration in the flue gas at the top of the tower can generally be kept between 50-200 ppm. .
I spoke with the production staff, and they said that the concentration of nitric acid coming out of the tower is generally around 55%. Are there any measures that can increase this concentration? Do you mean that the exhaust gas level at the top of the tower, 50-200 ppm, is before ammonia reduction?
Measures to increase the acid concentration at the outlet of the nitric acid absorption tower typically include: 1. Optimizing the ratio of the feed gases to ensure complete reaction. 2. Increasing the operating pressure in the absorption tower helps to improve the absorption efficiency. 3. Increase the height of the absorption tower or add more packing layers to provide a larger contact area, thereby facilitating thorough gas-liquid contact and reaction. 4. Improve the efficiency of the cooling system to control the temperature inside the absorption tower, preventing overheating from shifting the reaction equilibrium in the direction of nitrogen oxide formation. 5. Use high-efficiency absorbents or add additives to enhance the absorption effect. The NOx concentration of 50–200 ppm in the flue gas at the top of the tower mentioned generally refers to the level before reduction; after denitration treatments such as selective catalytic reduction (SCR) or selective non-catalytic reduction (SNCR), the NOx emission concentration can be further reduced. The ammonia reduction process can convert NOx into N2 and water, thereby reducing the amount of NOx in exhaust gases. .
Thank you, I’ve learned: handshake.
I really don’t understand the issues in this area
65%~68%, with NOx levels in the exhaust gases generally kept at 100 ppm
It is difficult to reduce the NOX concentration in exhaust gases to below 200PPM