Equipment & services to improve
A continuous chip moisture measurement to improve digester operation and cooking liquor dosage.

The Valmet online wood chip moisture measurement has been designed to acquire chip samples, detect moisture (0-70%) and return the sample to the feed stream. Valmet expertise in the use of microwave technology to measure moisture content in paper and board has been extended to the difficult application of chip water content. The primary variable, resonance frequency, is compensated against variations of material temperature and Q-value, which are defined by material density inside the measuring cell.

A sampling unit that provides continuous sample flow is installed on a vertical chute. The sample flow is retrieved from the main chip flow by a retrieval screw that is inserted into the chip chute. If chips are frozen, the collection chamber is heated to thaw the chips and allow consistent measurement. A return screw compresses the chips and pushes the sample through the Valmet CBA sensor and then into the downfall chute.

Chip Moisture Analyzer Impact
  • Accurate on-line chip moisture measurement before the digester or solid biofuel moisture before the power boiler
  • Real time measurement vs one sample per shift
  • Continuous measurement for more accurate process control
  • Non-ionizing radiation does not require any permission procedure

View brochure (pdf)