Project: Automatic Heating System #3 Head-Frame Brunwick Mine

The goal of this project was to heat exterior air before it was sent underground instead of vacuuming air from surface buildings. In the previous ventilation setup, air that was heated in some surface buildings was sucked underground wasting a lot of energy. On the Head Frame there existed louvers with an area sufficient to supply the same amount of air that was coming from the surface buildings. However this air needed to be heated in winter. Large steam coils where installed to heat this new fresh air. Six banks of louvers where equipped with energy efficient electric actuators that use a capacitor to store the required energy that would be required to operate the lovers in case of a power failure. This in effect replaces a spring, but without the continuous use of energy. The controller is an Allen-Bradley PLC5 controlling a 4" proportional steam valve. The temperature is kept at the required set point  (around 5C) using a PID. When at full steam (at about -20C outside), one of the 3 external bank of louver closes and one internal recirculated air opens. Like most system at Brunswick Mines, the system was integrated into PI with alarms being monitored on a Wonderware HMI .

Gilbert G. Godin ing.