Device and method for absorbing free sulfur trioxide in fuming sulfuric acid through concentrated sulfuric acid

[0022] Example 1

[0023] Inject liquid concentrated sulfuric acid with a concentration of 98.5% from the acid tanker into the circulation tank 9, and check in advance the niacin underground tank 1, the acid installation device 2, the 104.5% oleum storage tank 3, the inlet degassing pipe of the absorption tower 5. The exhaust fan 16, low-altitude discharge pipe 17, and other pipelines and valves ensure unobstructed air flow. Free SO escaped from 104.5% fuming sulfuric acid storage tank 3, acid storage device 2, and underground tank 1 3 Access from the lower part of the absorption tower. When the liquid level of the circulating tank 9 reaches 1m, the absorption tower circulating acid pump 15 is started, and the flow rate of the circulating acid pump 15 is about 8m 3 /h, the concentrated sulfuric acid is transported to the acid separation device 13 at the top of the absorption tower, and distributed uniformly from the top of the tower through the packing layer 12, and the free SO from bottom to top 3 Full contact and absorption of gas, SO 3 The gas is fully absorbed by the concentrated sulfuric acid to generate concentrated sulfuric acid. The generated concentrated sulfuric acid flows into the circulation tank 9 for recycling. At that time, the liquid level of the circulation tank 9 reaches 0.98m. Open the automatic water addition valve on the automatic water addition pipe 18 of the circulation tank, and the water addition is guaranteed to be 0.1 m 3 /h. As the absorption time increases, the liquid level of the circulation tank 9 gradually rises. When the liquid level exceeds 1m, it flows into the underground tank 1 through the overflow pipe 4, and the liquid level of the circulation tank is always maintained at 1m. After the exhaust fan 16 is started, the inlet air volume is about 1000m 3 /h, SO in low-altitude emission tail gas 3 The content is 43mg/Nm 3 ,Discharge.

[0024] Example 2

[0025] Inject the 98% concentrated liquid sulfuric acid from the acid tanker into the circulation tank 9, and check the underground tank 1, acid installation 2, oleum storage tank 3, absorption tower inlet degassing pipe 5, and exhaust fan in advance. 16. Low-altitude discharge pipe 17 and other pipelines and valves ensure unobstructed air flow. Free SO escaped from 104.5% fuming sulfuric acid storage tank 3, acid storage device 2, and underground tank 1 3 Access from the lower part of the absorption tower. When the liquid level of the circulating tank reaches 1m, start the absorption tower circulating acid pump 15, and the circulating acid pump flow rate is about 8m 3 /h, the concentrated sulfuric acid is transported to the acid separation device 13 at the top of the absorption tower, and distributed uniformly from the top of the tower through the packing layer 12, and the free SO from bottom to top 3 After the gas is fully contacted and absorbed, the concentration of concentrated sulfuric acid rises slightly and enters the circulation tank 9, and the concentrated sulfuric acid flowing into the circulation tank 9 is recycled. When the circulation tank level is 0.98m, the automatic water addition valve on the automatic water addition pipe 18 of the circulation tank is opened. The amount of water added is guaranteed to be 0.08m 3 /h. The mass concentration of sulfuric acid in the control circulation tank is maintained at 98.5%. As the absorption time increases, the liquid level in the circulation tank 9 gradually rises. When the liquid level exceeds 1m, it flows into the underground tank 1 through the overflow pipe 4, and the circulation tank liquid level is always maintained at 1m. . After the exhaust fan 16 is started, the inlet air volume is about 1000m 3 /h, SO in low-altitude emission tail gas 3 The content is 40 mg/Nm 3 ,Discharge.

[0026] Example 3

[0027] Inject the liquid concentrated sulfuric acid with a concentration of 93% from the acid tanker into the circulation tank 9, and check the underground tank 1, acid installation 2, oleum storage tank 3, absorption tower inlet degassing pipe 5, and exhaust fan in advance. 16. Low-altitude discharge pipe 17 and other pipelines and valves ensure unobstructed air flow. Free SO escaped from 104.5% fuming sulfuric acid storage tank 3, acid storage device 2, and underground tank 1 3 Access from the lower part of the absorption tower. When the liquid level of the circulating tank reaches 1m, the absorption tower circulating acid pump 15 is started, and the flow of the circulating acid pump is about 6m 3 /h, the concentrated sulfuric acid is transported to the acid separation device 13 at the top of the absorption tower, and distributed uniformly from the top of the tower through the packing layer 12, and the free SO from bottom to top 3 After the gas is fully contacted and absorbed, the concentration of concentrated sulfuric acid rises slightly and enters the circulation tank 9, and the concentrated sulfuric acid flowing into the circulation tank 9 is recycled. When the circulation tank level is 0.98m, the automatic water addition valve on the automatic water addition pipe 18 of the circulation tank is opened. The amount of water added is guaranteed to be 0.08m 3 /h. The mass concentration of sulfuric acid in the control circulation tank is maintained at 99%. As the absorption time increases, the liquid level of the circulation tank 9 gradually rises. When the liquid level exceeds 1m, it flows into the underground tank 1 through the overflow pipe 4, and the liquid level of the circulation tank is always maintained at 1m. After the exhaust fan 16 is started, the inlet air volume is about 1000m 3 /h, SO in low-altitude emission tail gas 3 The content is 35 mg/Nm 3 ,Discharge.