How do I safely dispose of non working laptop?

Do you have an Apple Store near you? If so, you can take it to them and they will properly dispose of it for you.

Your other options are:

1. Give it to a friend or relative.
2. Donate it to your favorite charity.
3. Check your local area for sites that offer for the disposal of electronics.

Note: I am assuming that you have already removed any personal data from this device. If not, and since this notebook is non-working, the Apple Store would be your safest bet going forward.

You can turn them into Apple for recycling.

National Services - Apple

I may have some parts value if the screen was still working.

which model MacBook Pro?