Ease of use and consumer satisfaction is extremely important. If there is a way to make the toilet more clean and make the waste disappear without any smells/sounds/stains, that is a top priority.

Hi paulv, I’m involved in a similar project which is why I also recently joined this forum. Have you considered a pickup program so that individuals wouldn’t need to be responsible for waste treatment? Also, I believe participation rates would dramatically improve without urine diversion, though urine may be far more valuable separated, so economic value may drive this factor.

My goal is to design a sanitary treatment device that will be able to be inspected and approved as an alternative to septic tanks and municipal sanitary systems. The idea is to get the official approvals at state or national levels so that any homeowner could choose the off-grid system.

One reason is to treat human waste before it is mixed with other runoff (especially industrial and commercial) in a municipal system, because if properly treated the human waste can be used as organic fertilizer, a resource, not a waste. Once mixed with chemicals and industrial runoff, it is no longer suitable for use in the food chain.

Another reason is that the device would allow for off-grid installation. Together with roof water collection, solar photovoltaic power, biogas generation and passivhaus design, it would eliminate the need for centralized city services.

My background is in city administration, planning and building inspection. I don't have background in the chemistry and biology of how waste processing works.

I would prefer a high-tech solution in order to monitor and log the disinfection stage and prove that all waste was properly treated. It is important that the system notify the owner if there is a failure in the disinfection stage. I believe that this is the only way to get the equipment certified and approved for use in any home. Once disinfected, the only regulatory concern becomes overloading an area with nutrients. I would hope to have a system reliable enough to fertilize food gardens. I do not believe that a low tech system that relies on the owner to do the right thing at the right time will ever be accepted by regulatory agencies.

I am still learning about this field. At this time I am considering a design that has urine separation to gardens, batch baking of solids to disinfect, liquification, anaerobic biogas production and liquid fertilizer delivery to food gardens. However I am new to this and appreciate other ideas.

Dear paulv Anonymous,

In my opinion you are describing two possible low-tech scenarios:

- Black water (grey- brown- and yellow- waters are mixed) coming from flushing toilets (wasting water!):
Black water treated by Constructed Wetlands (CW) using gravity (no power used) with an onside self composting for sludge using again a simple small CW. Needs a septic tank!

- Grey water and dry toilet with or without urine separation
Grey water treated by a much smaller Constructed Wetlands (CV) using gravity (no power used) with a separated composting for collected faeces and kitchen leftovers outside the house.

You will find many CW examples for above within SUSANA-Library and within INTERNET.

Any way, may you give more background about your self and your good intentions?

Good Luck
Detlef SCHWAGER

I am looking for direction on a sanitary system for human waste that will be a replacement for septic system or municipal sanitary/Waste Water Treatment system. The system would be used in the US. Replacement costs per household are about US$10,000 for a septic system and $US5,000 for connection to municipal system. The system should cost less than $5,000 to purchase and install.

Here are some of the design goals:

System should be scalable from 2 to ? persons, full time use.
Urine should be separated and used for plant fertilizer
Fecal matter will be processed to produce fertilizer and/or biogas
Fecal matter will be treated to eliminate disease causing microbes (heat?)
Resulting fertilizer will be safe for plants used for human consumption.
The system will monitor temperature to ensure that adequate temperatures are reached
There will be a warning which does not permit removal of the resulting compost if it has not been adequately treated
There will be a log which documents treatment method parameters and is available for review by inspectors.
Treated fecal matter will be liquified and pumped to a planting area as fertilizer.
No human carrying of fecal matter is required.
No human contact with fecal matter is required.
Preferably only a limited amount of storage of fecal matter in process of treatment, quick processing method, quick transfer to fertilizing soil.
The system would be part of an off-grid system, so limited power use is desired.

Is there any treatment method that has potential to achieve these design goals?