Reconciliation Methods for Yield Loss and Moisture Distortion in Reclaimed Paper Ledgers
Reconciling reclaimed paper ledgers requires converting scale intake weights to bone-dry fiber mass using core probe testing per ISO 287.
Microwave Moisture Attenuation
Sensor Technology
Electromagnetic signals change their intensity as they pass through a moving web of paper on a production line. Measuring microwave moisture attenuation provides a non-contact method for determining the water content of the sheet in real time. This technology is superior to infrared sensors for heavy board because it penetrates the entire thickness of the material.
Calibration Accuracy
Precise tuning of the sensors is required to account for the grammage and the temperature of the paper. When using microwave moisture attenuation, the instrument measures the loss of energy as the waves are absorbed by the water molecules. This data is then converted into a moisture percentage that the control system uses to adjust the steam flow in the dryers.
Production Monitoring
Automated systems use this information to maintain a consistent moisture profile across the entire width of the reel. Because microwave moisture attenuation works at the speed of the machine, it allows for immediate corrections to be made before any waste is produced. This capability is vital for high-speed converters who require stable moisture levels for successful gluing and folding operations.
Modern mills integrate these sensors into their quality management software to provide a permanent record of every reel produced.