Special fabric ammonia-containing exhaust gas circulating purification and recovery technology

Abstract

The invention discloses a special fabric ammonia-containing exhaust gas circulating purification and recovery technology. The special fabric ammonia-containing exhaust gas undergoes ammonia source classification, cooling, filtering and compression, then two-stage water washing and acid washing purification are carried out to form a circulating system in order to make the ammonia-containing exhaustgas absorbed into an absorption liquid with an ammonia nitrogen concentration of 6000-8000 mg / L and clean tail gas which can be discharged, the absorption liquid is deaminated by utilizing a deamination system, and purification and concentration are performed by combining ammonia-containing steam and exhaust liquid ammonia. A semi-bamboo-tube-shaped combined tower plate is innovatively adopted toimprove the steam stripping effect, so the ammonia nitrogen removal efficiency can reach 99% or above; ammonia steam is used as the absorption mother liquid, the exhaust liquid ammonia is directly absorbed, and ammonia nitrogen is recycled on the basis of the jet flow absorption principle to form ammonia water with a concentration being 20% or above, and the ammonia nitrogen concentration of theabsorption liquid is reduced to 15 mg / L or less; and the absorption liquid fully exchanges heat, is cooled, and then is reused for a washing section for recycling to form a closed ammonia-containing exhaust gas circulating purification and recovery system, so the recovery cost is reduced, and zero emission of wastewater is realized.

Description

technical field [0001] The invention relates to the technical field of ammonia-containing waste gas treatment, and more specifically relates to a special fabric ammonia-containing waste gas circulation purification and recovery process. Background technique [0002] Ammonia nitrogen in wastewater is one of the main substances that cause water eutrophication and environmental pollution. The hazards of ammonia nitrogen wastewater to the environment and human health mainly include the following points: ①It is easy to cause a large number of algae and other microorganisms in the water, which makes the operation of the tap water treatment plant difficult and causes drinking water odor; ②The dissolved oxygen in the water decreases, and a large number of fish die. It may even lead to the drying up of lakes; ③Increase the amount of chlorine used in water supply disinfection and industrial circulating water sterilization, which is corrosive to some metals (copper); ④When sewage is re...

AI Technical Summary

Problems solved by technology

Although the biological purification method does not produce secondary pollution, its treatment capacity is low and it is not suitable for industrial applications; the physical absorption method through water washing is the main method for treating ammonia-containing tail gas traditionally, but due to technical limitations, this method cannot The ammonia recovery rate is low, the water consumption is large, the dilute ammonia water formed consumes a lot of energy in the concentration process, and the added value of the recovered ammonia water is low

Moreover, the ammonia content of the washed tail gas is still relatively large, and it needs to be burned to produce a certain amount of NOx, causing secondary pollution; the catalytic decomposition method is to decompose NH3 into N2 and H2 under the action of a catalyst, but this method It needs to be carried out at high temperature, and the energy consumption is high; the catalytic oxidation method of ammonia converts NH3 into N2 and H2O through a catalyst, and does not produce secondary pollution, but the concentration of ammonia gas treated by this method is low, and it is not suitable for relatively high concentration For the treatment of ammonia, otherwise the temperature needs to be increased, which not only increases energy consumption but also promotes the formation of other nitrogen oxides. In addition, the catalytic oxidation efficiency of ammonia is also easily affected by the concentration of hydrogen in the mixed tail gas. lower conversion rate

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