PROBLEM TO BE SOLVED: To spread nitrogen to particulate matters.SOLUTION: A particulate matter conveying unit 100 comprises: hollow shafts 112, 110 in which a rotary shaft 103 of an auger 102 rotating inside a guide cylinder 101 for guiding particulate matters, guides nitrogen fed from a nitrogen feeding unit; and a nitrogen feeding filter cylinder 114 which is formed in a cylindrical shape and connected to the hollow shafts, and allows the nitrogen guided by the hollow shafts to be ejected from the inside to the outside so that the nitrogen is included in the particulate matters. Since the particulate matter conveying unit 100 is formed in a hollow shaft shape, the nitrogen can be ejected from the inside to the outside of the particulate matters, and thereby it is possible to spread the nitrogen to the particulate matters.
