Chinachem (xiamen) special materials co. LTD

Column:Waste gas treatment Time:2019-07-24
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1. Project introduction


1) overview


Chinachem (xiamen) special materials co. LTD


Boiler installation of three sets of oil burning boiler, pot burning exhaust through the exhaust pipe directly pollutes the surrounding environment, according to the law of the People's Republic of China on environmental impact assessment law ", the "regulations on the administration of construction project environmental protection", "the list of classified management of the construction project environmental impact assessment" and other relevant provisions, the chroma of project must exhaust governance, and new environmental protection facilities.


The treatment process includes flue gas system, water circulation system, dosing system, aeration system and automatic control system.


The spray foam tower adopts tangential wind to make the airflow rotate and rise. Two layers of spiral nozzle composite layer are arranged above the flue gas inlet. Above the nozzle layer is the porous foam tray layer. The whole tower is divided into upper, middle and lower towers. The flue gas discharged from the boiler enters the swirl section of the spray foam tower tangentially, and the dust with larger particle size is combined with the water curtain under the tray and discharged at the bottom of the tower. Flue gas continues to rise in tower body, the first layer 2 atomizing nozzle washing, absorption and removal of fine particles of soot and SO2, smoke rise by 2 layers of foam plate again, be full of absorbing liquid porous pan-ku bubble formation has a huge foam layer of the surface of liquid membrane, plate at the same time has the maximum liquid film on the surface area of aerosol, smoke diffusion in this stage as well, thus further remove fine dust and remove SO2, ultimately achieve high desulfurization efficiency of dust removal.


2. Governance scheme


(1) design parameters

According to the test report and data provided by the factory, the main design parameters are determined as follows: the smoke volume ≤30000m3/h, the flue gas temperature at the outlet of the air preheater ≤180℃, the dust concentration at the outlet of the air preheater ≤2500mg/m, the sulfur content of coal ≤0.8%, the system resistance in front of the dust collector ≤ 1.0kpa, the desulfurization efficiency ≥90%, and the dust removal efficiency ≥98.2%.

(2) treatment technology

The process includes flue gas system, water circulation system, dosing system, aeration system and automatic control system.

(3) working principle

The spray foam tower adopts tangential wind to make the airflow rotate and rise. One or two spiral nozzle composite layers are arranged above the flue gas inlet. Above the nozzle layer is the porous foam tray layer, and the spray distributor is arranged on the tray. The whole tower is divided into upper and lower tower bodies, or upper, middle and lower tower bodies (when using 2-layer tray). The lower tower body is circulation tank and liquid seal drainage tank. The flue gas discharged from the boiler enters the swirl section of the spray foam tower tangentially, and the dust with larger particle size is combined with the water curtain under the tray and discharged at the bottom of the tower. Flue gas continues to rise in tower body, the first layer 2 atomizing nozzle washing, absorption and removal of fine particles of soot and SO2, smoke rise by 2 layers of foam plate again, be full of absorbing liquid porous pan-ku bubble formation has a huge foam layer of the surface of liquid membrane, plate at the same time has the maximum liquid film on the surface area of aerosol, smoke diffusion in this stage as well, thus further remove fine dust and remove SO2, ultimately achieve high desulfurization efficiency of dust removal. Washing and absorption are carried out on the gas-liquid two-phase liquid film interface. The larger the liquid film area, the higher the dust removal and desulfurization efficiency. The mist in the flue gas is purified, rises slowly in the upper tower, enters the high-efficiency compound dehydrator through the connecting pipe between the tower body and the dehydrator, and then passes through the flue into the induced fan to the chimney for standard discharge. After absorbing SO2 alkaline water in tower, pH lower quickly, into the circulating tank and boiler alkaline wastewater rendezvous, through dosing system, will be more than 200 mu of MgO style flour Mg (OH) 2 emulsion, by pH control dosing automatic control instrument of electric valve, adjusting the pH inside the pool, use tower cleaning solution pH value of 6.5 or so. The circulating water in the pool is aerated by blast, and the desulfurization product is oxidized to MgSO4 soluble in water. In order to prevent sulfate supersaturation in the tank, some circulating water should be discharged, which accounts for about 2% of the total circulating water.