Hi,
Yes, you can implement BCM without SAP NetWeaver Process Integration. The functionality of SAP BCM are as under :-
1) Create Batch for Payments
2) Payment Approval Work List
3) Approval Workflow Authorization
4) Digital Signatures
5) Receive Status Messages
6) Bank Statement Processing
PI is basically used for Routing / Mapping of data, Security Encryption and it also comes with SWIFT Integration package.
Without PI, the files will not get encrypted and needs to be manually pushed into the bank's website.
Warm regards,
Akhil Poddar