METHOD AND APPARATUS FOR CLEANING OFF-GASES Russian patent published in 2019 - IPC B01D50/00 

FIELD: technological processes.

SUBSTANCE: keywords: absorption, filtering elements, vortex contact device, ozonized water, vapors and fog of acids, nitrogen oxides, sulfur oxides. Invention relates to cleaning exhaust gases emitted into atmosphere and can be used in chemical, petrochemical, metallurgical, enrichment industries, heat engineering, as well as in galvanic machine building. Cleaning of waste gases is carried out by means of at least two-step absorption by ozonized water and passing through filter elements with subsequent removal of liquid phase for recovery of trapped components and emission of purified gases into atmosphere, wherein ozone excess not dissolved in water is fed into gaseous phase of any of the absorption steps preceding the final step. Plant for cleaning off-gas includes: fog trap 1 with a vortex contact device, a dirty gas phase inlet branch pipe 2, a gas phase outlet branch pipe 3, inlet 4 and outlet 5 branch pipes of liquid phase; cascade of at least two series-connected single-stage vortex absorbers 8, 9 with branch pipes of inlet 10, 11 and outlet 12, 13 of gas phase, branch pipes of inlet 14, 15 and outlet 16, 17 of liquid phase; unit for producing ozonized water 24 consisting of ozonator 25 with control unit, ejector 26 and optionally circulating vessel of ozonized water 27 and pump 28 for its pumping. Besides, the installation includes the cleaned gas discharge pipe 22, exhaust fan 23, the liquid phases collection tank 29 before recycling and pump 30 for their transfer, as well as circulating 31 and overflow 32 hydraulic locks and pipelines for supply, transportation, distribution and removal of gas and liquid phases. Last absorber 9 in the direction of gas phase movement has an additional branch pipe 33 changing into an internal pipe located perpendicular to the lower part of the apparatus coaxially with the vortex contact device 35 and extending into its center for supply of ozonized water from circulation vessel 27 or ejector 26 of the ozonized water production unit 24 directly into contact device 35.

EFFECT: invention enables to create a universal waste gas cleaning unit for operation in a wide range of flow rate and off-gas concentration fluctuations, achieve steam, foggy of acids, nitrogen oxides and sulfur oxides of not less than 99,99 %, reducing capital and operating costs and simplifying the off-gas cleaning process, improving collection of trapped acid for its return to production or processing.

2 cl, 2 dwg