The PCV is not a single component, it's the whole system. The black box on the side of the block is the oil separator and the first part of the PCV (positive crankcase ventilation) system. The old one is likely to be rather stuck and brittle, so be a bit careful and if you break the neck off don't let pieces fall down into the crankcase.

I gather from your comments you did find a flametrap element located just above the separator box in the base of the rubber hose connected to it. In the schematics I was looking for it at the other end of the hose. Checking and cleaning that element should become part of your routine maintenance, at least every second oil change (or even every oil change if you find it gets dirty). The original style coil metal elements can be a pain to clean if they get caked.

Your PCV hoses seem a bit different from what I see in the Volvo parts schematic diagrams (which may be for an older B19 engine), but the principles are the same. I was editing my post, so make sure you go back and read my additional comments about oil leaks and seal conditioners compared to the initial automated reply that you received from the Brickboard system. Composing and editing long posts here can be a pain in that regard.
--
Dave -still with 940's, prev 740/240/140/120 You'd think I'd have learned by now