Large Volume Inorganic Chemicals - Ammonia ... - ammk-rks.net

Chapter 11.4.7 Recovery of NO x from exhaust gasesDescriptionIn the example plant (production of explosives), NO x is recovered from exhaust gases from thereaction, feed tanks, centrifugation and buffers by scrubbing (see Figure 1.7). The first threeabsorption towers are operated with water, the last with H 2 O 2 . H 2 O 2 is used to oxidise NO:NO + NO 2 + 2 H 2 O 2 2 HNO 3 + H 2 O2 NO 2 + H 2 O 2 2 HNO 3This improves the absorption efficiency drastically and the emitted NO x consists of >98 % NO 2 .Emissionto airExhaust gasesloaded with NO xH 2 OH 2 O/H 2 O 2ScrubberScrubberScrubberScrubberHNO 3 55 %for re-useFigure 1.7: Recovery of NO x from exhaust gases with a scrubber cascadeAchieved environmental benefits• efficient recovery of NO x from exhaust gases• emission levels of 113 – 220 mg/Nm 3 have been achieved.Cross-media effectsEnergy and H 2 O 2 consumption.Operational dataOperational data of the example:• volume flow to scrubber cascade: 7700 m 3 /hour• scrubbing medium in the last scrubber: H 2 O 2 15 %.Large Volume Inorganic Chemicals – Ammonia, Acids and Fertilisers 21