The height of chimney required for effective disposal of 27 kg/h of SO2 emission is
42 m is answer
For the small boilers using coal or liquid fuels, the required stack height with the
boiler shall be calculated by using the formula
H = 14 Q 0.3
Where H = Total stack height in metres from ground level
Q = Sulphur dioxide (SO2) emission rate in kg/hr
In no case, the stack height shall be less than 11 metres