Method for recycling oxygen in boiler flue gas ozonation denitration process

Abstract

The invention discloses a method for recycling oxygen in a boiler flue gas ozonation denitration process, which comprises the following steps of: adsorbing, separating and recycling mixed gas of which the oxygen mass concentration is not less than 95 percent into an oxygen storage tank, and supplementing oxygen prepared by an oxygen source preparation device to ensure that the oxygen mass concentration in the oxygen storage tank is not less than 90 percent; adjusting the pressure of the mixed gas in the oxygen storage tank to be 0.1-0.11 MPa; introducing the mixed gas in the oxygen storage tank into an ozone generator to generate ozone; enabling the mixed gas in the ozone generator to enter a mixed gas buffer tank and then enter a pressure swing adsorption tower to adsorb and separate oxygen; ozone enters the reactor to react with nitrogen oxide in the flue gas, so that the adsorbed oxygen in the pressure swing adsorption tower enters the oxygen storage tank again through the booster pump, the oxygen in the boiler flue gas ozonation denitration process is recycled, the energy consumption is reduced, and the purpose of reducing the operation cost of the whole process is achieved.

Description

technical field [0001] The invention relates to the field of ozone oxidation and denitrification of boiler flue gas, more specifically, it relates to a method for recycling oxygen in boiler flue gas ozone oxidation and denitrification. Background technique [0002] The boiler flue gas ozonation denitrification process uses active molecular ozone (O 3 ) to oxidize the pollutants in the flue gas, the most important thing is to oxidize the insoluble NO, NO 2 and other low-valent nitrogen oxides are oxidized to water-soluble N 2 o 5 , NO 3 At the same time, oxidize zero-valent mercury into soluble divalent mercury, oxidize dioxins, VOCs and other substances, and then combine these pollutants with SO in the original flue gas by using a wet scrubber 2 , HCl, HF and other soluble acid gases are washed and removed together. [0003] In boiler flue gas ozone oxidation denitrification technology, denitrification is to oxidize low-priced nitrogen oxides to high-valent nitrogen oxi...

AI Technical Summary

Problems solved by technology

[0008] In the existing boiler flue gas ozone oxidation and denitrification process, the mass concentration of ozone, an effective component of oxidation and denitrification, is very low, and most of the oxygen is a useless component of the oxidation and denitrification process. This part of oxygen causes direct waste and increases the operating time. Power Consumption

According to the reaction calculation, the removal of 1 kg of NOx by ozone oxidation and denitrification of flue gas requires about 1.67 kg of ozone to be consumed during normal operation. Calculated based on the ozone mass concentration of 10% after the ozone generator, the oxygen content of about 80% is 13.36 kg. Operate according to the existing process This part of oxygen causes waste; oxygen can be produced through molecular sieves to produce oxygen or air separation to produce liquid oxygen, and the power consumption for generating 1kg of oxygen is about 0.75kWh, so removing 1kg of NOx will result in a waste of electricity of about 13.36×0.75=10.02kWh, The waste of electric energy is huge, and the cost is greatly increased

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