High-quality tar production from coal in an integrated reactor: Rapid pyrolysis in a drop tube and downstream volatiles upgrading over char in a moving bed

•An integrated reactor was developed to combine coal rapid pyrolysis and volatiles upgrading.•Rapid pyrolysis in the upper drop tube guaranteed the high-yield production of tar.•Combining volatiles upgrading in the lower moving bed improved the tar quality.•The degree of volatile-char interaction could be controlled by temperature and char bed thickness.•Combining rapid pyrolysis and volatiles upgrading achieved the high-quality tar production from coal.