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In the paper, the production of wood vinegar from Chinese fir sawdust (FS), cotton stalk (CS) and bamboo sawdust (BS) by carbonization process was addressed. The wood vinegar yield was investigated and the organic compounds contained were determined by gas chromatography and mass spectrometry. It was found that the refined wood vinegar yield of FS increased firstly and then decreased with increasing carbonization temperature and the highest yield reached about 25% in 350–450 °C. The relative contents of acids and ketones from FS decreased and that of phenols increased with increasing temperature. The relative contents of acids and phenols in the wood vinegars produced from the samples were in the order of BS > CS > FS and that of ketones reversed. KCl solution treatment caused a decrease in the relative contents of the phenols and ketones, but an increase in that of the acids in FS wood vinegar.

The Chinese lignite upgrading process with high temperature nitrogen as a drying agent using a horizontal fixed-bed reactor was addressed and a kinetic model for the single particle lignite drying process was developed based on the experimental results. The results show that the lignite drying process consists of two stages, one is drying rate increasing stage and the other is drying rate decreasing stage. The lignite drying process can be promoted by initial nitrogen temperature increasing and lignite particle size decreasing. The effective diffusivity coefficient ( D e ) of the moisture from the lignite particle during the drying process with different initial temperature was obtained theoretically by calculation. The activated energy of the moisture emission from the lignite with different particle size (10–25 mm) was also obtained.