Rapid Determination of Moisture Content in Wood Logs
会议名称：《The 18th European Biomass Conference and Exhibition》
会议日期：2010年
学科分类：082902[工学-木材科学与技术] 08[工学] 0829[工学-林业工程]
摘 要：For rapid determination of the moisture content in wood logs numerous measuring devices are available on the market;their price ranges from 10 to 800 Euros. Comparative measurements with 12 wood log samples in a usual moisture range show that only few measuring devices can provide satisfying results concerning accuracy and repeatability when compared to moisture results from using a drying cabinet. Moisture content readings higher than 30 %（i.e. 43 % wood humidity based on dry matter） should in most cases be interpreted carefully. The true moisture content is almost consistently underestimated by the rapid test devices. The three devices with the highest accuracies showed a mean relative deviation of-2.9 to 5.9 %, but the deviation was usually higher than 10 %, particularly for the devices applying the dielectrical principle. Among the devices using the electrical conductivity method the instruments with ram electrode were superior. The correct use of the terms moisture content（wet basis） and the term wood humidity（dry basis） as common in the timber industry is sometimes questionable in the accompanying technical documents.