Method and device for thermal activation oxidant and steam combined synergistic flue gas purification

Abstract

The invention provides a method and a device for thermal activation oxidant and steam combined synergistic flue gas purification. The device comprises a bubble tower, a solution heater, a solution circulating pump, a flue gas inlet, a clean flue gas outlet, a steam inlet, a flushing water system, a demister and a bubbler. Strong-oxidation hydroxyl radicals (.OH) or sulfate radicals (SO4<->.) are generated by thermal activation decomposition of hyperoxides to serve as oxidants for oxidative removal of SO2, NOx and Hg<0>; steam is sprayed through steam inlets to form a moisture oversaturated environment in the upper portion of the bubble tower, growth of fine particles carried by flue gas is promoted by heterogeneous coagulation of water drops on surfaces of the fine particles, and the large drops with the fine particles are removed through the demister. The device is simple in structure, small in floor area, low in cost, capable of realizing simultaneous removal of flue gas pollutants including sulfur oxides, nitric oxides, heavy metal element mercury and fine particles and free of secondary pollution in a removal process and has a promising market application prospect.

Description

technical field [0001] The invention relates to a method for removing SO from coal-fired flue gas 2 , NO X , Hg 0 A device and method for fine particulate matter, in particular to a device and method for synergistically purifying flue gas with thermally activated oxidant and steam. Background technique [0002] SO produced in thermal power generation, industrial production, etc. 2 , NO X , Hg 0 And PM2.5 (particulate matter with an aerodynamic diameter less than or equal to 2.5 μm in the atmosphere) can cause serious air pollution problems such as acid rain, photochemical smog, carcinogenesis and smog. The discharge of these pollutants and fine particles is harmful to human health and ecology. The environment has caused great harm. Therefore, developing effective desulfurization, denitrification, demercury, and fine particulate matter removal methods for coal-fired flue gas is one of the important tasks of environmental protection researchers around the world. Althoug...

AI Technical Summary

Problems solved by technology

The simultaneous use of these two processes can effectively control SO 2 and NO X The amount of emissions in the atmosphere, but the goal of desulfurization and denitrification cannot be achieved in the same reactor at the same time, resulting in the complexity of the entire system, large footprint, high investment and operating costs, etc.

In addition, with the increasing requirements of human beings for environmental protection, relevant departments are gradually promulgating laws and regulations for the control of flue gas mercury emissions, but there is currently no effective mercury removal technology that has obtained large-scale industrial applications

In addition, the removal efficiency of existing coal-fired flue gas dust removal equipment can reach 99% for large particles, but the removal efficiency for fine particles is not high, and the removal efficiency drops sharply with the decrease of particle size, so Cause a large amount of fine particles to enter the atmosphere, causing serious environmental pollution - smog

If a separate flue gas demercury system or devices and equipment for controlling fine particulate matter are added to the tail of the existing desulfurization and denitrification system, it will inevitably further increase the initial investment and operating costs of the entire system, and it is difficult for any enterprise to bear the huge investment and operating costs, so it is difficult to obtain large-scale industrial applications in developing countries

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