Flue gas purification system for hazardous waste incineration and purification method

A flue gas purification system for hazardous waste incineration, comprising:

• a cooling deacidification coupling device for hazardous waste incineration flue gas;
• wherein the cooling deacidification coupling device comprises:
• a reaction tower (1), a spraying device (2), a first liquid inlet pipe (201), a second liquid inlet pipe (202), a gas inlet pipe (101), a gas outlet pipe (102), and an output pipe (103);
• wherein a top of the reaction tower (1) is installed with the spraying device (2), an inlet end of the spraying device (2) is connected to the first liquid inlet pipe (201) and the second liquid inlet pipe (202), the first liquid inlet pipe (201) is configured to transmit a cooling substance, and the second liquid inlet pipe (202) is configured to transmit a deacidification substance;
• and the spraying device (2) is provided with a liquid outlet, and the liquid outlet of the spraying device (2) is configured to spray out a mixture of the cooling substance and the deacidification substance after the cooling substance enters the spraying device (2) through the first liquid inlet pipe (201) and the deacidification substance enters the spraying device (2) through the second liquid inlet pipe (202);
• wherein the reaction tower (1) is connected to the gas inlet pipe (101) and the gas outlet pipe (102);
• a bottom of the reaction tower (1) is connected to the output pipe (103) configured to output solid salts generated in the reaction tower (1);
• wherein the flue gas purification system further comprises:
• an incineration device (3), a heat recovery boiler (4) and a selective non-catalytic reduction (SNCR) denitrification device (9);
• wherein the incineration device (3) is connected to the reaction tower (1) through the heat recovery boiler (4), and a gas outlet end of the heat recovery boiler (4) is connected to a gas inlet end of the gas inlet pipe (101);
• the selective non-catalytic reduction (SNCR) denitrification device (9) is disposed in the heat recovery boiler (4);
• wherein the spraying device (2) is configured to mix the cooling substance from the first liquid inlet pipe (201) and the deacidification substance from the second liquid inlet pipe (202) with a flue gas after the flue gas enters the reaction tower (1), thereby achieving cooling and deacidification simultaneously in the reaction tower (1);
• and
• wherein the flue gas purification system further comprises a dust collection device (10) and a collection device (11);
• an inlet end of the dust collection device (10) is directly connected to an outlet end of the output pipe (103), an outlet end of the dust collection device (10) is connected to the collection device (11), and a gas discharge end of the dust collection device (10) is connected to an inlet end of the second liquid inlet pipe (202);
• and the dust collection device (10) is configured to return gases with dust-removal containing alkaline powder to the reaction tower (1), thereby achieving repeated recycling.