How to maintain the combustion temperature in WSA sulfuric acid production at low concentrations
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This post was last edited by liaifeng on 2018-8-15 at 18:28. In the WSA process for sulfuric acid production, the temperature of the combustion furnace is required to be between 950–1100°C. If the concentration of hydrogen sulfide in the feed gas is low, how can the combustion temperature be maintained? Can air alone be sufficient to ensure this temperature?
Fuel gas also needs to be burned to reach the desired temperature.
If only hydrogen sulfide is burned, there is no need to control the furnace temperature at such a high level; another consideration is required when burning waste acid.
The feed gas is not sufficient to raise the temperature enough; sufficient heat must be provided by increasing the fuel gas, as air alone cannot supply heat
At what temperature can sulfuric acid be produced by burning only hydrogen sulfide?
It was once kept between 900-920 for a while; as long as complete combustion occurred, it didn’t matter what the concentration of sulfuric acid was. What is your hydrogen sulfide concentration? What is the highest temperature reached in the furnace when it is burning only hydrogen sulfide? Does this affect the concentration of sulfuric acid? What changes will occur if the hydrogen sulfide feed is increased to its maximum level? For example, what happens to the furnace temperature, furnace pressure, and acid concentration?
The hydrogen sulfide content in acidic gas must not be less than 15%; if it is below this value, fuel gas must be burned alongside it
Three methods: 1. Preheating of air and acidic gas; 2. Adding a suitable proportion of fuel gas to the acidic gas; 3. Using an oxygen-enriched process (that is, the air used for combustion is not ordinary air but air with a higher oxygen content)
The current concern is that the hydrogen sulfide concentration is too low; the heat generated by the combustion of hydrogen sulfide is not sufficient to meet the requirements for combustion
The auto-ignition temperature of hydrogen sulfide is around 260; to prevent incomplete combustion, fuel gas can be added for combustion assistance, and the use of heat tracing as mentioned above is necessary.
Additional fuel gas is burned to maintain the furnace temperature.