[Closed] $6.50 KQ river fold?

Usually I just fold preflop. It's not worth risking a lot of chips for the 50 chips in the pot. However, it is definitely ok as you are in position and can hit strong TPs.
As played I check behind the turn. In case he has the flush this will save you chips and in case you are still in front he probably doesn't have too much outs. In case he is on a flushdraw now you won't lose a lot of chips on the river in case he hits.
As played I fold as well. As you said he could have flush, trips and a set and your line looks pretty strong until the river.

Result:

No Limit Holdem Tournament
$6.00+$0.50
9 players
Converted at weaktight.com

Stacks:
UTG (1270)
UTG+1 (1500)
MP1 (70)
MP2 (1490)
MP3 (2950)
CO (1770)
Hero (BTN) (1470)
SB (1480)
BB (1500)

Blinds: 10/20

Pre-flop: (30, 9 players) Hero is BTN Q♠ K♥
UTG calls 20, 5 folds, Hero raises to 100, 2 folds, UTG calls 80

Flop: T♣ K♦ 6♣ (230, 2 players)
UTG checks, Hero bets 150, UTG calls 150

Turn: 2♣ (530, 2 players)
UTG checks, Hero bets 300, UTG calls 300

River: 6♠ (1,130, 2 players)
UTG goes all-in 720, Hero folds

Final Pot: 1,130

UTG wins 1,850 ( won +580 )
Hero lost -550