The dew point control system hood ventilation technology controls the supply and exhaust air quantities in the dryer section, thus reducing the amount of air and fresh steam required.
The dew point control system consists of sensors that measure the moisture in the hood exhaust air and a control algorithm that ideally tracks the supply and exhaust air quantities through speed control at the fans. Either constant exhaust air moisture is the basis for the control, or a stored product grade/air quantity matrix is used. This is advantageous in for machines with a high portion of dirt in the hood exhaust air, since as a rule exhaust air moisture sensors do not have sufficient measurement stability there. By using the dew point control system, the power requirement at the ventilator drive is reduced. This is true since air quantity reduction of 30% reduces power requirements by more than 60% with speed control of the fans. Accordingly, the fresh steam requirement and the air leakage from the hood (exhaust air quantity minus supply air quantity) are also reduced. Heat recovery performance increases as well.
The dew point control system hood ventilation technology is used in the air system of the dryer section and reduces the quantities of air, saving steam and power in the overall process.