An Early O.O.R.B.S. Prototype

For nearly 6 years O.O.R.B.S. has been in development, and in that time it has seen a multitude of iterations and refinements. We did not originally intent to develop an entirely new system, instead it grew out of the need for an ecologically friendly way to provide balanced nourishment for growing plants. At first we started with very basic aerated basins, but from there it quickly grew in sophistication and efficiency to become the truly unique solution that it is today.

A better composter?

Early on we were simply looking for an efficient way to recycle the nutrients locked up in garden waste and kitchen scraps. After trying a variety of different composting methods, it became apparent we needed something that would be faster, easier and less smelly! Knowing that bacteria were key to this process, we looked to existing techniques that focused on bacterial growth, such as aerated compost tea and sequencing batch reactors. However, every system we tried eventually ran into issues.

Simple aerated basins

After evaluating a variety of different approaches, from anaerobic digesters, to updraft composters, the benefits of liquid aerobic digestion quickly made it the preferred method, but we still had to settle on the best technique.

Compost basket

At first the techniques developed to make simple compost tea looked promising, but it soon became apparent that the process was little better than regular composting. We still had to compost using tradition vermicompost methods, odor remained an issue, and the nutrient solution wasn't strong enough to stand on it's own.

Increasing Aeration

In the hopes of finding ways to speed the process up and increase the nutrient concentration, we looked to aerated basin techniques used by the wastewater industry. On the surface it seemed like these systems would be able to handle whole kitchen scraps, allowing for a single unit system. In principle, bacteria in these systems would break organics down into a slurry that could then be applied directly to the garden. However, this also meant large increases in the amount of aeration required.

Promising start

Although the aerated basin techniques initially appeared very promising it quickly became apparent just how difficult it was to maintain a stable system. As food loads increased, the system became less and less efficient, requiring ever greater inputs of energy to ensure adequate oxygen and proper mixing.

Erupting freezers!

This converted freezer, erupting foam all over the yard like a giant science fair volcano, perfectly illustrates the problem. Maintaining a stable system with adequate aeration meant that the system needed constant monitoring and adjustment. It also quickly escalated the complexity, size and power requirements necessary to make it run smoothly.

An evolving process

As we continued to attempt to overcome the challenges of achieving our goal, we were soon experimenting with new designs. We attempted to use larger air pumps, circulation pumps, even mixing paddles, but each new solution brought it's own host of issues to overcome.

Frothy beer mug

Although this design also proved to be a dead end, it remains one of our favorites, as it looks like a giant frothy mug of beer!

Vortex rings!

Eventually we decided that we needed to find an entirely new solution. So we went back to the drawing board and once again looked to nature, and found the answer had been staring us in the face all along. Fluid dynamics; This was afterall a liquid system, so how does nature optimize the mixing of fluids? pressure differentials and vortices.

Testing the dynamics

So we got to work designing a system that would take advantage of fluid dynamic principles to control flow patterns. The aim was to harness the powerful mixing properties that govern the storm cloud formation. Here we use smoke to test the for the formation of vortex rings.

Taking shape

Early on most of the focus was on controlling the flow dynamics in the reactor, which originally included the use of a mesh cage, a feature we have since been able to eliminate.

Proving the concept

Here we test the basic concept on a small scale to verify that the dynamics will behave as predicted.

O.O.R.B.S. is born!

Success! At this point we were able to verify that the basic concept would be viable in principle, but we still had a long road ahead to optimize a system for real world use.

Initial trials

We quickly got to work building a very basic test unit to work out where we needed to focus when designing a prototype.

Prototype time!

It was time to go big! we decided on 35 us gallon capacity tank for the original prototype's main tank, as we felt that should give us the ability to test heavy loads.

The ORB!

Although a feature no longer in use, by shear coincidence the mesh basket in the original prototype proved to be very ORB like in shape.

Reactor chamber

This basket allows food to be agitated and broken down inside the reactor while allowing the liquid fraction to recirculate through the main tank. It was designed to create very specific regions of high and low pressure if the system, with both high and low shear.

Redesigning the air diffuser

Flow patterns aside, the most important design consideration of O.O.R.B.S. was the air diffuser. As aeration is the key to making the system work, we knew this was going to be our biggest challenge. This was one of our first attempts. One problem with diffusers traditionally used in other systems is that they have a tendency to clog as debris settles on the bottom of the tank.

Uncloggable diffuser

We needed to find a way to clear debris that would otherwise settle and clog the diffusers. This meant designing a diffuser that would allow debris to pass unimpeded into a separate settling tank that can be removed for cleaning without shutting the system down. Here we assemble our first design, it has gone through several iterations since.

Applying membrane to the diffuser

We also looked at a myriad of different membrane materials to find the optimal balance between durability, bubble size and backpressure but we always found that the efficiency was not sufficient to meet our design needs. However, in the end we eliminated the membrane all together, creating an entirely new approach to air diffusion with unprecedented results!

Putting it all together

A working prototype

The first working prototype of the O.O.R.B.S. system!

Splash guard

Bubble bubble

Real world testing

After a few more quick modifications for ease of use, it was time for O.O.R.B.S. to prove itself.

Adding kitchen scraps

After initial success with garden cuttings, we quickly moved up to kitchen scraps.

Agressive aggitation

The system worked better than we could have hoped, aggressively breaking down things like these avocado pits, pulled out of the system in this partially digested state after only 48hrs.

Down to the bone

As shown here the system also quickly stripped all the meat fat and gristle from these bones. Even the bones themselves eventually disappeared.

Mark 2

Learning what we could from the first prototype, we constructed a second version that further improved on both efficiency and ease of use.

Pushing the limits

In order to work out the systems limitations, and how we could overcome them, we needed to push the system hard. As the unit could handle far greater loads than a single household could provide, we invited the neighbors to add their scraps as well. Soon this one unit was composting all the kitchen scraps from 4 households!

Determining capacity

We found that this tank, with a 20 gallon reactor chamber could happily process roughly 7 gallons a week of mixed kitchen scraps. this gave us a ratio of roughly 1/3 solids to liquid ratio without affecting flow patterns.

Handles it all! (almost)

To date O.O.R.B.S. has proven itself capable of handling ANY type of organic waste. This includes, meat, bone, dairy, even seaweed. Of course somethings take longer than others, but when operated properly it safely deals with all the things normal compost can't. Best of all it does it without stinking up your yard!

Treating Sewage!

To ensure that the system was truly safe and effective we had extensive 3rd party testing conducted periodically. But to really claim that O.O.R.B.S. can SAFELY handle ANY organic waste we needed to put our money where our mouth was! It was on that note that we conducted independent testing with raw human sewage! The results speak for themselves. O.O.R.B.S. quickly eliminated BOD and fecal coliforms.

O.O.R.B.S. Pellets

As organic waste breaks down in the system it is cycled through a complex food chain that frees up the nutrients locked within and converts them into forms available to other living organisms. At first this takes the form of a liquid high in nutrients in a form readily available to plants, but if the process continues they get taken up into these dense little granules that collect in the settling basin once reaching sufficient density. In essence; slow release fertilizer pellets.

Ongoing research

Of course all this didn't mean we had finished development. This entire time we continued to look for ways to improve over the existing prototype; increasing efficiency and refining the system wherever possible.

The Current Prototype

This brings us to the present iteration. O.O.R.B.S. as it is today. We've managed to significantly reduce the overall dimensions by further increasing efficiency. This now means the unit can handle solids concentrations as high as 2/3 the system volume! The system is even faster and easier to use. But don't take our word for it. Check out O.O.R.B.S. for yourself and see what happens when human innovation meets natures inspiration!