Bergström, Dan
- Institutionen för skogens biomaterial och teknologi, Sveriges lantbruksuniversitet
Sammanfattning
According to the Swedish Timber Measurement Act, measurements affecting payments for wood fuels to landowners must be accurate and precise. In this regard, moisture content is an important quality parameter for wood chips which influences the net calorific value as received and thus the economic value. As standard practice moisture content is determined with the oven-drying method, which is cumbersome to use for deliveries to facilities without drying-ovens, which in turn necessitates that samples are taken elsewhere for measurement. An alternative solution is to use a portable moisture meter. Our aim was to evaluate the precision of a handheld capacitance moisture meter. Accuracy and precision of a capacitance meter was determined in the lab and a calibration function was made. Thereafter, the calibrated moisture meter was compared with the standard method for moisture content determination of truckloads of chips. The capacitance meter showed a moderate accuracy by underestimating moisture content by 6.0 percentage points (pp), compared to the reference method, at a precision of +/- 3.8 pp (CI 95%). For chips with M> 50%, both accuracy and precision decreased. Calibration increased the accuracy in the follow up study by 3 pp for chips with M
Nyckelord
biofuels; heating value; payment
Publicerad i
Silva Fennica
2018, volym: 52, nummer: 5, artikelnummer: 6993
Utgivare: FINNISH SOC FOREST SCIENCE-NATURAL RESOURCES INST FINLAND
SLU författare
UKÄ forskningsämne
Skogsvetenskap
Publikationens identifierare
- DOI: https://doi.org/10.14214/sf.6993
Permanent länk till denna sida (URI)
https://res.slu.se/id/publ/98309