Yes, PRORATIONS is a Scrabble word!

Letter values in Scrabble US: P 3, R 1, O 1, R 1, A 1, T 1, I 1, O 1, N 1, S 1.

Is it a valid word?

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

the proportional limitation of production or distribution of something (e.g. crude oil or natural gas) to some fractional part of the total capacity of each producer