As of Release 4.6C, you can send credit memos to the vendor if you return consignment and pipeline withdrawals to consignment stock.
The list of withdrawals settled or to be settled is created using the ALV grid.
In earlier releases, you could create only invoices for consignment and pipeline withdrawals.
For more information, see the SAP Library at Logistics Invoice Verification -> Automatic Settlements -> Consignment and Pipeline Settlement.