expel, cast off, arrange
摒 centers on forceful removal or rejection: expelling something unwanted, casting it off, or arranging things by clearing away what doesn't belong.
摒 combines 扌 (hand) with 屏, which likely contributes both sound and the idea of screening or removing. The exact historical development is uncertain.
A hand 扌 beside 屏, which resembles a screen or barrier. Picture a hand pushing something away past a screen, expelling it or casting it off.
For ヘイ, imagine a hand sweeping away clutter and saying 'Hey!' as it expels the mess: Hey -> ヘイ.