Promotion-chasing Chesterfield should have equalised in the 41st minute but Adam Rundle missed an open goal and two minutes later Vale increased their lead when a free-kick dropped to Richards.
It got worse for the hosts when Richards thumped in an unstoppable shot from the edge of the area in the 50th minute.
Richards completed his hat-trick 10 minutes from time with a close-range header before Craig Davies converted an 85th-minute penalty after Alan Goodall was red-carded for bringing him down.
Source: Team Talk
Source: Team Talk