Method and system for decarburization through complete combustion of boiler as well as desulfurization, denitration and dust removal of exhaust gas

Abstract

The invention belongs to a technical field of atmospheric air control and treatment of exhaust gas from coal fired boilers and relates to a method and a system for decarburization through complete combustion as well as desulfurization, denitration and dust removal of exhaust gas. The method for the invention includes the decarburization of 30% oxygen-rich gas in combustion. The invention also includes that sulfur trioxide as well as other mixed acid are formed in a reaction of 30%ozone-rich gas and sulfur dioxide and nitrogen oxides in exhaust gas with water containing PX purified liquid. Exhaust gas which is treated through desulfurization and denitration is soaked into a 100 nm-500 nm wet nano filter in water containing PX purified liquid for removal of PM 2.5 dust particles. Advantages: the decarburization through complete combustion is promoted by oxygen-rich gas and the desulfurization and denitration is promoted by ozone-rich gas. A wet nano filter is used for removal of PM 2.5 dust particles. Reaction products are acid liquid and superfine powder particles which can be used in industry and civil application. No desulfurized gypsum is generated and no sulfide or nitrides will be discharged. Thus the formation of atmospheric acid rain can be prevented; pollutions of PM 2.5 dust to atmospheric air can be solved through the dust removal. Collected 2.5 Mu m dust can be applied in an industrial material field as a material. Therefore, purposes of mineral resource saving and turning waste into wealth can be reached.

Description

technical field [0001] The invention belongs to the technical field of atmospheric air treatment and flue gas treatment of coal-fired boilers, and in particular relates to a method and system for desulfurization, denitrification and dust removal of flue gas. Background technique [0002] Zhejiang University's Chinese patent application CN200610053090.6 "Coal-fired boiler flue gas ozone oxidation simultaneous desulfurization and denitrification device and its method" discloses a coal-fired boiler flue gas ozone oxidation simultaneous desulfurization and denitration device and its method. The method comprises the following steps: 1) spraying ozone O at a low temperature section of 110-150°C before or after the electrostatic precipitator 5 of the boiler flue 4 3 , the molar ratio of ozone sprayed into the nitrogen oxides in the boiler flue gas is 0.5 to 1.5, and the low-valence nitrogen oxides insoluble in water in the boiler flue gas are oxidized into high-valence nitrogen oxi...

AI Technical Summary

Problems solved by technology

[0003] One of the disadvantages of this invention is that the ozone gas containing 21% concentration made by ordinary air containing only 21% oxygen is passed into the flue, and the oxidation effect of sulfide and nitride in the flue gas in the flue is not as good as 30% concentration The ozone gas oxidation effect of the ozone gas is good; the second is that the temperature of the flue gas at the position where the ozone gas is introduced into the flue gas is in the low temperature range of 110-150 °C, which also makes the oxidation effect of ozone on the sulfide and nitride in the flue gas in the flue gas less than 500-600 °C. Strong ozone with 30% ozone in the high temperature section has a good effect

The disadvantage is that the neutralization of the air pollution source sulfur dioxide in the lye will cause secondary pollution and increase the cost. It is better to dissolve the air pollution source sulfur dioxide directly in water to form dilute sulfuric acid at low cost and prepare it as a product to turn waste into treasure.

At the same time, there is no technical innovation method such as collecting and processing the 2.5 micron series dust in the flue gas and preparing it as an ultrafine powder material for use in the field of industrial materials

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