I just tip the spent compost onto the veg plot and flower beds as a sort of mulch. My pots often end up with slugs and weevils so wouldn’t reuse it in pots but feel spreading it on the beds let’s the birds eat any nasties.
That's what I do.
Based in Sussex, I garden to encourage as many birds to my garden as possible.
thank you @Danae(dan-Ah-ee) for the link to Alice Fowls' article. Has anyone actually used cat litter? It is interesting but won't it absorb a lot of water that should go to the plant? Will the plant need more watering?
Another vote here for tipping it onto beds though I may use some from last years melons to fill hanging baskets with nasturtiums as they don’t like the soil too rich.
I think life is too short to sterilise compost, and wouldn’t it be cheaper to buy new?
I turn my pots out, into old compost bags. I leave it for a few months to let any roots rot away. When I reuse it, I liven it up with some fertiliser, plus a bit of fresh compost. Sometimes if filling a large pot I use old compost in the bottom and fill up with fresh, it depends on what I am growing. BTW I turn the old bags inside out, so I immediately know which bags have old compost in them and which have fresh.
Posts
https://www.theguardian.com/lifeandstyle/2019/may/18/how-to-reuse-old-compost-alys-fowler#:~:text=Ideally%20you%20then%20cut%20the,it%20to%20be%20planted%20up.
Luxembourg
BTW I turn the old bags inside out, so I immediately know which bags have old compost in them and which have fresh.