Jamieson, Fausset and Brown on Leviticus 9:17-21

17-21. meat offering ... wave offering--It is observable that there is no notice taken of these in the offerings the priests made for themselves. They could not bear their own sins: and therefore, instead of eating any part of their own sin offering, as they were at liberty to do in the case of the people's offering, they had to carry the whole carcasses "without the camp and burn them with fire" [Ex 29:14; Le 4:12].