Upvote:3
You'll need some identity document to travel because in China you are obligate to carry at least one identity document with you. See China Idendity Card Wiki
A passport photocopy can be treated as a official document since it be recognized by Chinese officials.
For this you'll need to validate your photocopy in any notary's office or maybe in a Chinese Consulate.
Or as last option you can request in your country consulate a provisory identity document which allows you to flight inside the China.