Ok, so this being my first Volvo.... what exactly is a flametrap? I'm assuming it's some kind of filter to prevent oil from getting into the intake, correct? I see it under the intake and it looks extremely dirty on the outside.

Does it replace a PCV valve?
Can I remove it clean it, and if so, how?
And does it even have a filter that can be replaced?

Any info is appreciated! Oh, and this is the B234F engine. I know a lot about cars, but this is new to me.

 

Exactly...what Volvo calls a flame trap is indeed positive crankcase ventilation. There is a white plastic insert that has perforations...it can be replaced or cleaned. A side effect of the system is that it places oily vapor back through the throttle body for more complete combustion. Not only the flame trap gets filthy. The throttle body gets filthy as well. The throttle blade can get so much crud on it that it will not close completely and consequently not allow the TPS to sense that the throttle is closed. This results in the ecu not activating the idle air control. Makes for poor idle!.
More about service here...Scroll down to the B234 section
Engine. Seals, Belts, Crankcase Ventilation