What happens if the oxygen content in the acid-producing flue gas is low?

The oxygen content is indeed low; this is a situation I am very familiar with. When performing two-stage compression and two-stage absorption, a targeted design is necessary. The most familiar case of acid production to me. This post was last edited by Peach blossoms are in bloom on 2009-3-3 13:02.]

Could the moderator explain in more detail? It would be great if they could introduce a similar industrial setup as well. Thank you

The oxygen content is too low; could there be an error in your analysis data? Is your production process for acid based on pyrite? A low oxygen content results in a low conversion rate of sulfur dioxide.

Of course not; air can be added. I’ve just never seen this kind of process before

In your case, acid production is carried out with a low carbon-to-oxygen-sulfur ratio. There are similar plants in China, such as the 200,000-ton gypsum-based acid production plant in Lubei, which operates in a manner very similar to yours.

If it’s as the poster said, then it can be said that your conversion system has virtually no conversion efficiency at all. According to the conversion formula for sulfur dioxide: SO2 + 1/2O2 = SO3 + Q, to convert 1 volume of sulfur dioxide into 1 volume of sulfur trioxide, 1/2 volume of oxygen is required. In your plant, however, there is 9% sulfur dioxide but only 0.5% oxygen, which is far from enough for complete conversion. It is recommended that your factory pay attention to the ratio between the air volume at the bottom of the furnace and the amount of material fed into it during the operation of the boiling furnace, and improve the operational practices. If that doesn’t work, an additional air supply hole can be added at the inlet of the drying tower (on the PVC pipe), which can increase the initial sulfur dioxide concentration in the flue gas, thereby facilitating the conversion process. These are my personal opinions; please feel free to correct me.

Is it okay to supply air at the outlet of the electrostatic fog purifier? This is the standard configuration for producing acid from smelting flue gas; it’s just that the amount of supplementary air used isn’t as large

Air definitely needs to be added, it just depends on how much is appropriate.

Possible reasons for the situation you mentioned: the air-to-material ratio is too low, and it’s also likely that the impurity content in the raw material is too high. If the oxygen content is only 0.5 while sulfur dioxide is 9, then the conversion rate will definitely be very low. It is recommended to carry out the liquefaction production of sulfur dioxide. This post was last edited by limingshuguang on 2009-3-4 10:03.]

Increase the excess air coefficient of the boiling furnace; however, I still don’t believe that the value of 0.5 is accurate

The oxygen content is indeed very low; with such a low level of oxygen, even if it were used entirely for the oxidation of SO2, the conversion rate would not be very high. I’ve heard that in the process of producing acid from smelting flue gases in copper production, air can be added – I’m not sure whether this approach would be suitable for your situation.

Add an air make-up pipe and a flow meter to the inlet pipe of the drying tower, with automatic valves used for regulation; the amount of air added is determined by the flow rate, which is quite convenient. These are my personal opinions.

What flue gas is used to produce acid? Lead, zinc? In any case, it is quite common to teach the production of acid from low-concentration flue gas. A low oxygen content isn’t a problem; after supplying air, the SO2 concentration stays above 5%, and using the conventional two-turn two-suction method is sufficient to maintain heat balance