Thought I'd mention here how I compost my kitchen green scraps, egg shells, etc and garden waste as I struggled to find anything about it here and think this is a good method and it works well for me.
I collect all green kitchen scraps over a year into a 100l water butt, 2 bed, 2 people house. At the bottom it's filled with gravel and it has a tap and I regularly drain any liquid and use it around the garden. I also add any shredded paper into that water butt that we collect at the same time, mail, random flyers, etc.
After a year, partly rotten at this point, I transfer it all into a tumbling composter, this then further compost over spring and summer and in the following autumn I get it all out, fully dried at this point but clumpy and not that usable really and shred everything as per pics into a fine compost, ready to be used next spring.
Any of these garden shredders will work well with dried mostly composted stuff like this.
I normally grow tomatoes in it and get excellent results!