I have talked about this in my tips thread. If you are talking about garbage, process plastic, metal, electronic and rubber into better material through the crafting bench. Otherwise, just put it in an item box and sell it. I don't believe you get money for processed garbage, but you scan use the ones I listed for crafting.
Annoyingly, you do seem to get paid a small default amount of trash objects, but recycled scrap material is worthless; The crafting isn't filled out much yet so I'll semi-spoil > > > > > and tell you you do not need scrap papers and only need a tiny bit of scrap plastic, so its best to sell/dispose/burn paper and plastic trash since its very, very easy to get more of it anyway. Other trash is quite valuable to keep for recycling and crafting though.
