If you are trying to dispose of a piano, you might first try offering it for free on Craigslist, Freecycle, or Trashnothing. Alternatively, some piano moving firms offer disposal as a service for a fee.
If there is no value in your piano, please do not donate it to a church, school, university, or other institution. Although they may unwittingly accept the donation, their piano technician will then be faced with the same problem: What does one do with a piano with no value? Making a donation is a noble intention, but the responsible thing to do with a piano of no value is to pursue one of the other options above. If you are unsure whether your piano has any value, you will need to hire a piano technician (myself or another) to help make that determination.