This video shows RTI International’s Gates Foundation funded toilet running a full-loop on the solid processing side for one of the first times.
The cycle, shown below in the diagram, processes human feces into a burnable material using the heat created by burning an earlier processed batch of feces. Motors, actuators, a whole lot of stainless steel (amongst other materials), Programmable Logic Control and LabVIEW, along with a lot of clever engineering and skilled fabrication have brought the system to a point where the concept has now been more than proven!
Next we move forward with reengineering and improving to reduce thermal losses, reuse extra thermal energy to start powering portions of the system, and trying to achieve a better mass balance in which we are able to dry feces at the same rate that we are able to burn it.
The last week of December saw a major milestone, as our first batch of feces was dried solely by the combustion of previously-dried feces on the current Beta system set-up in our lab at RTI!
Our feces combustor, engineered by our partners at Colorado State University, is shown running semi-automated; National Instruments’ LabVIEW controls the pressure differential through the system and displays/records temperature data as “fuel” (dried human feces) is manually metered into the combustion chamber using two ball valves as an air-lock.
The heat from combustion is used to dry the human feces applied to the cast-iron automated rotating plate inside the dryer apparatus.
Next, we begin working toward a fully-automated, fully-closed loop in which feces is dried, scraped and ground, then metered into the combustion chamber for burning.
First and foremost we’ve started evaluating the use and efficacy of a different type of electrochemical cell in the liquid disinfection system itself. This electrochemical cell is adapted from a commercially available consumer product, which is good for several reasons, chief amongst them: potential lower cost and energy requirements.
During this evaluation, we’ve found the initial test results to be very encouraging! (see below)
The photo on the left shows a tank of urine and feces prior to electrochemical treatment. The photo on the right shows the same after treatment.
Urine and Feces disinfection test results
Plot of E. coli concentration and energy consumption over the course of a treatment test.
The 90 L tank test
We are also in the process of testing a larger 90 L processing tank.
During field trials of the RTI toilet, liquid waste processing will be carried out once a day. This process needs approximately 90 L of waste to complete.
Due to the larger size of this processing tank, tests are currently being carried out to understand how this level of scaled up processing would impact the overall function our toilet.
Those results will be posted here as soon as they are available!
The first stage of the solid waste processing module consists of an auger-based dryer/conveyer unit.
The auger is a helical screw device Jerseys designed to move and dry the feces before and converting Abra it into solid fuel for combustion. Heat from in the combustion process accelerates drying, wholesale nfl jerseys while mechanical apertures along the auger length generate cheap nba jerseys burnable sized pellets of uniform wholesale jerseys size. This video shows some preliminary sizing experiments performed using Bill miso paste as a surrogate. Uniform – sizing facilitates combustion and optimum How energy conversion on the back end of the solid waste processing module.
The Engines and Energy Conversion Laboratory at Colorado State University, under the co-leadership of Dr. Morgan DeFoort, are an essential part of the solution to efficiently process and extract energy from human feces.