I'd say "no", but see below. Truly separate accounts would normally have to be created on the server. Each would have its own address, username, password, mailbox etc. Some servers do allow for a "catch-all" address, such that anything in front of the @ is accepted, and all relevantly addressed messages are fed into a common mailbox. If your server does this, then you could create such addresses in Thunderbird (look for "Manage Identities" in Account Settings). Note that all such messages would come to whoever runs or works with the "main" account, so you wouldn't have any easy means to automatically apportion these to separate staff members. But if it's all for yourself then it may suit you. It comes down to whether or not your chosen server supports a catch-all address.