The main equipment commonly used in the desulfurization system is the main equipment such as absorption tower, flue, chimney, desulfurization pump, supercharged fan, and the anti-corrosion resistance of the desulfurization pump, absorption tower, flue, chimney and other parts. It is now described.
Application of absorption tower and chimney
Wet flue gas desulfurization environmental protection technology (FGD) due to its high desulfurization rate, wide coal application, process technology matures, long-standing period, small load changes, high flue gas treatment capacity, etc., is widely used in each Large, medium-sized thermal power plants, becoming the dominant process technology of flue gas desulfurization in domestic and external thermal power plants. However, the process is also strong in corrosion, and the treatment of flue gas temperature, SO2 absorbent liquid solid content, strong wear resistance, large equipment, high quality requirements, high quality requirements, anti-corrosion failure maintenance. Therefore, the corrosion control of the device has always been one of the key issues that affect the long period of the device.
Wet flue gas desulfurization absorption tower, the choice of chimney inner cylindrical corrosion material must consider the following aspects:
(1) Meet the corrosion requirements in the complicated chemical conditions: the chemical environment in the chimney is complex, the smoke has a high amount of acid, and the condensate formed on the surface of the inner lining is strong for most building materials. Therefore, the lining material requires strong acid corrosion resistance;
(2) Temperature requirements: the flue gas temperature difference is large, the flue gas temperature after wet desulfurization is between 40 degree C to 80 degree C, under the maintenance of the desulfurization system or not operation, the smoke temperature in the chimney is in the chimney Between 130 degree C 150 degree C, the liner is required to have a resistance to temperature difference, which does not crack and durable during a frequent temperature change;
(3) Wear resistance: The flue gas contains a large amount of dust, and at the same time under the action of corrosive media, the actual situation of wear may be more obvious, so the anti-corrosion material is required to have good wear resistance;
(4) Has a certain anti-bending performance: Since some chimneys, including the motion, seismic and wind effects of the earth itself, the chimney, in particular the high-altitude portion, the angle may occur or deviate, while the chimney Some uncontrollable mechanical functions may occur during installation and transportation, so the anti-corrosion material is required to have a certain bending performance;
(5) has a good bonding force: the anti-corrosion material must have a strong bond strength, not only refers to the high bond strength of the material, but also high bond strength between the material and the substrate, while the material is not easy. Cracking, hierarchical or peeling, adhesion, and impact strength, thereby ensuring better corrosion resistance. Usually we require the bonding force of the primary material and steel structure to be at least 10MPa
