Abstract: An industrial plant includes a flue gas processing system, a stack which receives a flue gas from an industrial process, a flue gas processing unit, a suction line connected between the stack and the flue gas processing unit, a fan arranged in the suction line, a sensor which provides a signal representative of a gas flow rate or a change thereof through a discharge outlet of the stack, a controller which regulates a flow through the suction line based on the signal, and a flow restriction arranged in the suction line upstream of the fan. The discharge outlet is open to the atmosphere. The fan draws the flue gas from the stack to the flue gas processing unit and has a control arrangement which controls a pressure in the suction line upstream of the fan and downstream of the flow restriction or a pressure differential across the flow restriction.