关键词: 异位发酵床, 垫料, 电特性, 稻谷壳, 温度, 含水率, 快速测量

Abstract: In order to explore the relationship between dielectric properties and moisture content of rice husk in ectopic fermentation bed, and to explore the feasibility of dielectric properties in the rapid measurement of moisture content of bedding materials,rice husk,which is the main bulk material of ectopic fermentation bedding materials,was taken as the research object,the effects of measurement signal frequency (0.1—100 kHz), temperature (15—55℃ ) and moisture content (10%—70%) on the dielectric properties of rice husks were studied by using parallel plate capacitor.The reason of the change of the dielectric constant of rice husks was analyzed.At a signal frequency of 1 kHz,5 kHz,10 kHz and 50 kHz,the model was established to predict the moisture content of rice husk by measuring the relative dielectric constant and temperature.The results showed that in the frequency range of 0.1—100 kHz,the relative dielectric constant and relative dielectric loss factor of rice husks increased with the increase of temperature and moisture content,and decreased with the increase of the signal frequency.Under the selected frequency,the regression model which can express the relationship between relative permittivity,temperature and moisture content by quadratic polynomial was established.The determination coefficients of all the models were greater than 0.98,indicating that the moisture content of the rice husk can be predicted by the dielectric properties.

Key words: Ectopic fermentation bed, Bedding materials, Dielectric property, Rice husk;Temperature, Moisture content, Rapid measurement