yes you can add them to the bin, no the seeds won't necessarily be destroyed .... it takes high temperatures to eliminate seeds .... but you could just avoid adding the seeds, do your weeding before they flower!

Bill

If you have the space- building a conventional compost pile and running a hot-cycle will take care of a lot of weed seed and digestability issues with components. The down-side is that many local (notice that I avoided the word "native" :) worms will be introduced as well.

I process a lot of material- so it happens in open piles outdoors. Turns out that in my garden I have so many worms that I need to re-mulch with shredded leaves several times in the summer! My vermicomposting, however, is greatly simplified by this approach. I simply pile materials between rows and cover with cardboard to prevent leaching nutrients, and let 'em at it.