Current issue: 55(2)

Under compilation: 55(3)

Scopus CiteScore 2019: 3.1
Scopus ranking of open access forestry journals: 6th
PlanS compliant
Silva Fennica 1926-1997
1990-1997
1980-1989
1970-1979
1960-1969
Acta Forestalia Fennica
1953-1968
1933-1952
1913-1932

Articles containing the keyword 'biofuels'.

Category: Research article

article id 6993, category Research article
Lars Fridh, Lars Eliasson, Dan Bergström. (2018). Precision and accuracy in moisture content determination of wood fuel chips using a handheld electric capacitance moisture meter. Silva Fennica vol. 52 no. 5 article id 6993. https://doi.org/10.14214/sf.6993
Highlights: The studied capacitance meter can provide accurate estimates of mean moisture content for chips with M < 50% if a large sample is taken; It should be possible to use the capacitance meter to measure moisture content even for calculating payments depending of the needed accuracy; However a calibration function for each assortment is needed.

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 < 50% but could not be made for wetter chips. The oven-drying method and the capacitance meter can provide equally accurate estimates of mean moisture content for chips with M < 50% if a larger sample is taken with the latter. It should be possible to use capacitance meters to measure moisture content even when used to calculate payments depending of the needed accuracy. A calibration function for each assortment is needed.

  • Fridh, Skogforsk, The Forestry Research Institute of Sweden, Uppsala Science Park, 751 83 Uppsala, Sweden; Skogsägarna Mellanskog, Uppsala Science Park, Box 127, 751 04 Uppsala, Sweden ORCID ID: http://orcid.org/0000-0002-4721-1193 E-mail: lars.fridh@mellanskog.se
  • Eliasson, Skogforsk, The Forestry Research Institute of Sweden, Uppsala Science Park, 751 83 Uppsala, Sweden ORCID ID: http://orcid.org/0000-0002-2038-9864 E-mail: lars.eliasson@skogforsk.se (email)
  • Bergström, Swedish University of Agricultural Sciences, Department of Forest Biomaterials and Technology, S-901 83 Umeå, Sweden ORCID ID:E-mail: dan.bergstrom@slu.se

Register
Click this link to register for Silva Fennica submission and tracking system.
Log in
If you are a registered user, log in to save your selected articles for later access.
Contents alert
Sign up to receive alerts of new content
Your selected articles

Committee on Publication Ethics A Trusted Community-Governed Archive