If they can put a man on the moon, why can't they build a 'composter-friendly' under-sink disposal?
While this would have real potential if you could do it, as there are many people who do seriously get into composting (I am one who does try), it has some problems.

The main problem is how do you separate the water from the solids, while leaving it at least slightly wet. Compost needs some water content, and if you pack the solids too densely it won't decompose easily. You would almost need to re-hydrate the solids for them to be composted if you remove too much water.

So, how do you remove the water? I can see a few ways.


Filter it out. But any sieve that has holes in it that will allow water to drain out, but holds back most of the solids will get clogged too fast.
Squeeze it out, using some sort of trash compactor design. Again, one would need to work it out where the water goes, and then deal with the solids in an automatic way.
Centrifugal action, so something like a washing machine spin cycle.


Any of these schemes need to remove just enough water, but not all of it. It is not an easy problem to solve.

What we do, that seems to work, is leave a 5 gallon bucket in the garage. When we have kitchen waste, veggie peelings, etc., they go into the bucket. Every few days, I walk down to the compost pile with the bucket and a pitchfork and turn it over, adding the new material. This works quite well. (Another major part of our compost pile is shredded paper from our paper shredder, plus shredded leaf waste.)

This is a low tech solution that works splendidly well. Yes, some of the material would compost faster if it went through a disposal grinding process, but low tech often has advantages.


It is cheap.
It never needs repair. (Ok, some days my back hurts.)
No electricity required.
It gives me some exercise, never a bad thing.
It forces me to go out and turn over the pile once a week or more. This gets air into the pile, as well as tending to keep it free of animals due to the frequent activity (who would otherwise wish to nest in the pile.)