The Phazir is a rugged, portable and reliable hand-held unit, increasingly finding a place in commercial eucalypt forestry. Cheaper than laboratory-based instruments, in comparison studies, its precision and accuracy is only slightly less. If suitable calibrations exist, it is capable of predicting up to 8 properties from a single spectrum: each spectrum taking ~5 secs to collect. Combined with trusted calibrations, it empower forest growers to predict key wood properties in standing trees for very low cost.
Portable NIR
For the past 6 years we have been working with the Polychromix Phazir (now supplied by ThermoFisher), evaluating its potential to measure a range of wood properties (Downes et al 2009, Meder at el 2011)
in small samples taken from standing trees.
This can be done in real time:
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In the field using spectra obtained from green wood samples
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In the office using air-dried wood samples
Air-dry wood measurement
We have Phazir (935-1800 nm version) calibrations close-to-market readiness for the prediction of Kraft pulp yield and cellulose content using air-dry wood samples. Calibrations for the added measurement of basic densiity are well advanced. We have found the use of drill swarf from the outer 50 mm to be an effective sampling approach. Spectra can be collected from samples still in the plastic bag.
These calibrations can be easily uploaded to the Phazir and used in-house. Broad-scale, multi-site and species calibration are currently being developed.
Green wood measurement
Studies (Downes et al 2009) have shown the potential to measure moisture and cellulose content, pulp yield and density in green wood samples taken directly from the tree. Combining these into a robust application that works over sites and species has proved more problematic, given a commercially-useful degree of precision. The main issue revolves around the application of consistent sampling protocols, as relatively minor changes in technique affects the moisture content, which in turn impacts on calibration development and application.
http://www.fwpa.com.au/images/resources/PNC055-0708_NIR.pdf
Downes G.M., Meder R., Ebdon N., Menz D. and Hicks C. (2009) Quality Assessment of Australian woodchips Project 5: Field-based application of acoustic velocity and NIR as predictors of pulp quality across site and species FWPA PN07.3027 CSIRO Client report No. 1895