Kazim-Richards had an early chance to give Rovers the lead, but the striker could only put his header wide.
The summer signing then flashed his shot narrowly wide after being set up by Jason Lowe.
A final first-half opportunity for Rovers fell to Marcus Olsson, who could only blast his effort over the bar after cutting inside to create a shooting opportunity.
Hull's best opening came just before the break as Nick Proschwitz saw his shot blocked by Lowe.
Both sides struggled to create many opportunities in the second half as Kazim-Richards headed wide for the hosts before seeing his shot go harmlessly wide.
However, the striker finally made the breakthrough with 15 minutes left to play when he pounced in the area to get his second goal of the season.
The win has lifted Steve Kean's side up to fourth in the Championship table, while Hull stay 16th.