Is it practical to build a symmetric encryption cipher that needs to change the key for each process?

That's not something you can build into the cipher. A cipher is something like AES that's used as a low-level building block in something larger.

Key management policy is something you build into the cryptosystem and protocols that use the cipher. That's where you get into the key exchange and key agreement protocols.

The underlying ciphers can't enforce any sort of key policy. They're too low in the stack. They get the key long after it was chosen. The layers you build over them are responsible for key management policy.