Yes, BIN is a Scrabble word!

Letter values in Scrabble US: B 3, I 1, N 1.

Is it a valid word?

BIN is a valid word in the official Scrabble dictionary (US), the UK Scrabble Dictionary and Words with Friends (ENABLE).

a container; usually has a lid
the quantity contained in a bin
an identification number consisting of a two-part code assigned to banks and savings associations; the first part shows the location and the second identifies the bank itself

Also: bank identification number, aba transit number.

Not playable in Scrabble US: BINFUL.