Process for Oleum Manufacture

The height of the exhaust stack determines the maximum SO2/SO3 concentration in the ambient air surrounding a sulfuric acid plant. It is also well known that this concentration fluctuates widely in space and time due to the thermo-aerodynamic conditions of the low-level atmosphere (0-500 m). These conditions can vary due to the following factors  

a minimum stack height is generally prescribed by statutory authorities in all countries. In India it is the State Pollution Control Boards and the height is generally 30 m above ground level. 

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