Biomass Moisture Control for Pellet ProductionThe Moisture Control Problem

There is usually a biomass moisture content (MC) entering the pelletizers that produce the best pellet quality. However, biomass moisture content (MC) entering the dryer can vary significantly, thereby, preventing traditional MC sensing and control methods from maintaining the optimum target MC with a low standard deviation.

Delta T Moisture Control Solution

The Delta T MC Sensing and Control System solved the three main problems with currently-used MC sensing and control methods: These solutions are:

  • An “inside-the-dryer” MC Softsensor consisting of two ordinary temperature sensors and software that is rugged, reliable, does not drift, and does not require re-calibration.
  • An “inside-the-dryer” evaporative load softsensor.
  • A control algorithm that is capable or re-calculating the setpoint that maintains the target MC following evaporative load changes to the dryer.
  • Benefits of Delta T Solution

  • Maintains desired target MC to pelletizers with at least 30% less MC variation
  • Handles variations in feed MC, thus eliminating mixing and MC sampling of feed to dryer
  • Possibly monitor and control MC out of cooler using Delta T
  • Minimal operator input required
  • Figure (1) depicts MC control of biomass for pellets destined for power plant or domestic heating use after replacement of currently-used MC sensing and control system with the Delta T that maintains the target with at least 30% less MC variation. (Read Article)

    Figure (1)-Comparison of Delta T Vs Currently-Used MC Control