So simple that only a person with limited time,unlimited money, or Waste Management, would have a problem with it. I don't understand why every school, municipality and entrepreneur isn't doing this. The utilities also should be concerned, but given the apathy and laziness of most people, their business model is safe.
Maybe garbage disposal manufacturers would joint venture- all one needs is separate piping out and then back in.
Poop goes in a willow feeder. Wipe with this tiny ad: