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Industrial Ecology and Living Machines

A paper presented on October 27, 1998 to the 6th World Wilderness Congress in Bangalore, India by Michael Shaw

Spirit of Place: Great Blue Heron

Out of their loneliness for each other
two reeds, or maybe two shadows, lurch
forward and become suddenly a life
lifted from dawn or the rain. It is
the wilderness come back again, a lagoon
with out city reflected in its eye.
We live by faith in such presences.

It is a test for us, that thin
but real, undulating figure that promises,
"If you keep faith I will exist
at the edge, where your vision joins
the sunlight and the rain: heads in the light,
feet that go down in the mud where the truth is."

From Even in Quiet Places by William Stafford

At the Findhorn Foundation in Scotland, I learned to relate to nature in three ways.

Unity is the first way. As we expand our psyches to be as large as the world, we experience ourselves as nature and also as part of nature. Particularly in the wilderness we can have flashes of this peak experience of unity at a transpersonal level when everything seems to fall into alignment.

Cooperation with nature is the second way. We learn to work with nature like a good gardener. We see all processes as a part of natural ecosystems and we are in wonder and awe of the power and sophistication of nature's elegant ecologies. The basic idea here, is not one of dominance over nature, but living as part of nature.

Seeing nature as our teacher and as a model is the third way. The old motto "Natura mater et magistra" - nature is both mother and teacher - applies. The basic idea is that our industrial and development processes can be modeled on natural ecosystems. This is the field of ecological design and engineering and industrial ecology. I have watched my partner, Dr. John Todd, work in this way many times. For example, some years ago we were designing an engineered ecology to treat toxic sludge from the bottom of a highly polluted canal in Tennessee. John's design method was to look at the anatomy of the catfish and model the dimensions and ratios of our engineered systems on the guts of the fish. The catfish is capable of digesting sludge, and nature has produced a highly functional and elegant breakdown process. We could not do better than use this knowledge in the design of our systems. Bench scale tests that followed confirmed the basis of the design model.

Industrial Ecology

The field of ecological design and its application to industry, called industrial ecology, is relatively new. The UN University calls this approach "Eco-restructuring". The fundamental idea is to move beyond the typical industrial production and consumption models, which are linear and mechanistic, to close loop systems, which are similar to natural ecosystems. So we design an industrial plant or a new town or a hotel as a living system, which is an integral part of the larger bioregion. The inputs and outputs of the human engineered facilities are seen as typical of natural ecological sub-systems and the wilderness is taken as the greater whole in the design process.

It is the wilderness come back again,
a lagoon with our city reflected in its eye."
-- William Stafford.

At present, our industrial processes emphasize the moving of materials and energy from nature through the economic system as the primary way we "create value". The main economic activities are, therefore, producing and consuming. We might contrast this to a mature forest or pond. In these natural systems the processes of production and the consumption, including recycling of wastes and nutrients, are balanced processes. On the forest floor the decomposing organic matter recycles the nutrients and nurtures the trees. The limnology of a pond is a wonderful example of many interacting systems, with constant changes in the ecology, but a stable overall effect on the environment. The system balance and stability is only disturbed when we overload the pond with pollutants or too many nutrients from human systems.

Natural ecosystems have a large number of pathways and so can be called distributed systems. Species diversity reinforces the stability of these systems with redundancy in function. The result is self-organization, self-repair, self-reproduction, and a great ability to adapt to perturbations in external conditions. If industrial processes can have these same positive attributes, they will be highly effective and often restorative.

A previous speaker talked about a paradigm shift in our culture involving gender and attitude. She recommended that instead of seeing human activities as mainly centered in the workplace (in what is presently a male-dominated way of being), we shift our focus to the family as the primary way of living (which is more of the female milieu). With such a shift, many of the decisions we make in government, academia and industry will be very different. A similar paradigm change is happening as we begin to think about industry as part of, and not separate, from nature. In other words, human economic and industrial activities are living systems participating in the Earth's natural systems.

"Model the systemic design of industry on the systemic design of the natural system ... industrial ecology involves designing industrial infrastructures as if they were a series of interlocking human-made ecosystems interfacing with the natural global ecosystem ... The aim of industrial ecology is to interpret and adapt an understanding of the natural system and apply it to the design of the human-made system, in order to achieve a pattern of industrialization that is not only more efficient, but which is intrinsically adjusted to the tolerances and characteristics of the natural system." (Tibbs, 1992)

Living Machines™

So by modeling our human engineered systems on their natural counterparts, we can be aligned with the natural world and experience the benefits of integrated design. Engineering science adopts a whole systems approach, which leads us to the story of Living Machines™.

Living Machines™ were invented by Dr. John Todd, an eminent Canadian biologist, who has won many awards for his work in designing biological systems using the principles of ecological engineering. Living Machines™ can grow food, generate energy, clean the air, heat and cool buildings, but their primary application so far has been in wastewater treatment.

The basic ecological principles behind Living Machines™ have been laid out in an excellent paper by John Todd and Beth Josephson which is published in the Journal of Ecological Engineering called "Living Technologies for Wastewater Treatment". The twelve principles come from the study of natural systems, and they are then applied to engineered facilities. They include an adequate mineral basis to sustain life, nutrient flows and recycling, steep gradients such as the transition from anaerobic to aerobic environments, the presence of at least three distinct and complete ecologies (pond, marsh and meadow for example), the presence of adequate colonies of Bacteria, a physical connection between the engineered system and the wild, and species diversity.

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The basic principles in the field of ecological engineering were first put forward by Howard T. Odum in his book Environment, Power and Society over twenty years ago. The fundamental idea is that, in addition to modeling human designed systems on nature; we can use complete ecologies to carry out useful tasks. Living Machines™ are different from "dead machines" in that the main working parts are alive. Different ecologies can be linked to handle many inputs, self manage a multitude of internal, closed-loop functions and provide a variety of outputs.

We know that the pond, marsh and meadow are capable of generating the new and decomposing the old in complex ecological cycles. John Todd set out to use the ability of these natural ecologies to handle waste streams effectively and economically. The organisms that are present naturally in the pond, marsh and meadow are harnessed along with sunlight and gravity to handle pollution. Other inputs, particularly energy requirements from fossil fuels, are minimized. The primary product is water treated to advanced wastewater treatment standards, which is then available for reuse. In addition to the application of breakdown ecologies for purifying water, nutrients are recycled and useful products are grown, such as fishes and botanicals.

Ecologically engineered systems are capable of high levels of treatment. In fact, taking the last pieces of pollution out of a waste stream is often more economical using natural systems than with conventional and chemical processes. Also the beneficial features of natural ecosystems carry over to the engineered systems, including great stability of operation due to multiple biological pathways and diversity of organisms in the system, and the ability of Living Machines™ to self-organize, self-repair and self-replicate. We find that Living Machines™ treating food processing waste streams, where there are wide variations in influent characteristics, both in flows and loadings, provide stable high quality effluent.

A typical industrial wastewater treatment Living Machine™ is the Mars facility in Wyong, Australia. This food processing plant manufactures 350 products from over 1,300 ingredients, and produces a widely varying wastewater load. First the flow is equalized in a balance tank. From there it passed to an anaerobic digester, which provides a considerable amount of treatment, without the use of energy. In fact, if the organic loading is sufficient, methane can be produced which can be used for steam generation and so on. From the anaerobic reactor, wastewater flows to a closed aerobic reactor, which is connected to a biofilter. The biofilter consists of humic material, which is mainly bark and compost. The odors are scrubbed by bacterial action as they pass from the closed tank through the humic layer. The wastewater flow then passes to a series of open aerobic reactors, with plants racked on the water surface. The plant roots provide the media for the attached growth microorganisms that break down the organic materials in the waste stream. In addition any ammonia is nitrified to nitrite and then to nitrate. As the bacteria go through their life cycles and die, they form sludge, some of which is eaten by other creatures in the system such as snails. Living Machine™ sludge volumes are low compared to other wastewater treatment technologies, because the engineered ecologies digest organic materials as part of the process, however sludge needs to be removed in the clarifier, which follows the open aerobic reactors. The final step is polishing in Ecological Fluidized Beds (EFBs). These reactors were developed and patented by Ocean Arks International. They are fixed film submerged filters with a relatively high rate of internal recirculation.

The treated water from the Wyong facility (up to 400m3/day or 100,000 gpd) is collected in a quarter acre pond. From there it can be used to irrigate the 60-acre site, which has many acres of natural bush. Mars is currently investigating the possibility of growing fish in this holding pond.

Another Mars facility with a Living Machine™ is at Ethel M Chocolates in Las Vegas, Nevada. The waste stream comes from confectionery manufacture. The reactors are similar to those in Wyong, except there is no anaerobic reactor. The effluent is treated to advanced wastewater treatment standards and all the wastewater is reused on site for irrigation. Following the Living Machine™ train is a constructed wetland and holding pond, followed by UV treatment for sterilization. Water is recirculated between the holding pond and the constructed wetland to keep the pond fresh. The treated water is drawn from the pond to irrigate the extensive gardens. Odors from the closed aerobic reactors are scrubbed in a two-cell biofilter. The sludge generated in the Living Machine™ is sent to a vertical flow reedbed. This is a special design of constructed wetland, where the sludge solids are trapped on the surface among the reeds and compost over time. Water drains down through the wetland vertically and is sent back to the Living Machine™ for treatment. There is a natural reduction of around 97% of the organic material left in the reed bed. A humic layer builds up over a seven- to ten-year period and is used for landscaping. The reed bed is then replanted for on-going sludge treatment. Because this Living Machine™ recycles the treated water on site, scrubs the odors in a biofilter and treats the sludge in a reedbed, it is called a zero-discharge facility. Two thousand to three thousand visitors a day see the large variety of flowering plants and grasses growing in the Living Machine™.

Plants, grown in the tanks, provide an excellent substrate for bacterial treatment and use the nutrients in the wastewater for their own growth. In a facility in Vermont, over 250 species of plants have been researched for their suitability to provide root mass for wastewater treatment and valuable botanical byproducts. The most important output of a wastewater treatment Living Machine™ is, of course, high quality water, which can be reused for irrigation, washing, boiler makeup water, toilet water and so on. If water minimization is the goal for a building or a development, it can be achieved by using a vacuum collection system, which minimizes the requirement of water for toilets to 10% of what would normally be required. Living Machine™ treatment can enable 90% of the treated waste stream to be recycled. In this way water usage can be reduced to a few percent of the normal demand.

Other Living Machines™ are designed to grow specific botanicals or fish as by-products. In an industrial park in Indiana, orchids are grown for people's desks. Herbal tinctures and flower essences are made from plants in a Living Machine™ in northern Scotland. Koi are grown in a Mars Living Machine™ in Texas. The organic loading in a high strength industrial waste stream can be used to grow proteins, which in turn can be fed to fish. In Vermont, a prototype aquaculture facility is testing the use of waste heat from a power station as the main energy source and proteins grown from brewery spent grain as fish food. Two Living Machines™ in Florida provide habitats for collections of native Florida butterflies.

The greatest requirement for water in the world is irrigation. The following is extracted from the Guardian Weekly and is called UN moves to stave off water wars by Robin McKie.

"In India, lakes are poisoned by sewage; in Africa, rivers turn into filthy trickles; around Asia's Aral Sea, millions of people have been stranded as the waters shrink and dry up. Every day, more and more people suffer the same crisis: not enough water. Scientists calculate that 7 per cent of the human race does not have enough to survive. But much worse lies in store. Their figures show that this will rise to a staggering 70 per cent by 2050. Most of humanity faces a future without the most basic of resources.

"'We need water for drinking, keeping clean, and making things -- but, most importantly, we need it for farming,' said Professor Jim Wallace of the Institute of Hydrology in Oxfordshire. 'About three-quarters of the water we use goes on growing food.' Better use of irrigation water is central to the crisis, he added. 'We might be able to increase the world's arable land by about 10 per cent -- at the very most. But at the same time, the population will go up by 65 per cent. We therefore have to increase crop yields dramatically, and we can only do that if we make much better use of the water we use for irrigation.'"

Ocean Arks International - Restorer Technology

Ocean Arks International, a non-profit foundation which has worked in the development of these technologies since 1981, has designed a floating ecologically engineered system called a Restorer, which is used for bio-remediation of polluted natural bodies of water and for low-cost sewage and industrial wastewater treatment, particularly in the developing world.

Restorers float on lakes, slow moving rivers, canals or constructed lagoons to purify water. The technology is borrowed from an analogous component in nature known as the floating island. These islands are formed as dense mats of vegetation - typically made up of cattails, bulrush, sedge and reeds - extend outward from shoreline wetlands. As the water gets deeper the roots no longer reach the bottom, so they use the oxygen in their root mass for buoyancy, and the surrounding vegetation for support to retain their top-side-up orientation. The area beneath these floating mats is exceptionally rich in aquatic biota.

Eventually, storm events tear whole sections (sometimes several hectares) free from the shore. The islands migrate around a lake with changing winds, occasionally reattaching to a new area of the shoreline, or breaking up in heavy weather. As one naturalist described, "floating islands act like kidneys in a system, providing the oxygen rich surface area that keeps the ecosystem in balance during extreme seasonal fluctuations."

The first Restorer was launched in l992 on Flax Pond, near Harwich, Massachusetts. The on-going pollution is from leachate from a landfill. In l992, Flax Pond was all but dead with few fish or benthic organisms in the water and it was closed for swimming and fishing. Since that time the fish and benthic communities have regenerated as pollution levels dropped. The pond can now be used for recreation, including fishing and swimming. A local organic cranberry grower, who draws water from the pond, has seen his production increase fourfold in the last six years.

Restorers also treat sewage in lagoons. In many parts of the developing world sewage is put into "septic lagoons" with no treatment. These are sources of disease, generate multitudes of mosquitoes, and also cause river and ground water pollution. The floating Restorers provide treatment at relatively modest cost and in many cases the treated water with retained nutrients can be used for irrigation. A Restorer is a treatment technology that reduces BOD, COD, nitrogen, pathogens and so on by its own processes. It also acts as a chemostat. Beneficial bacteria and other microorganisms are continuously generated by the Restorer and discharged into the water body. It is the whole water body that then treats itself in combination with the Restorer. The Restorer also maintains positive dissolved oxygen in the water, ensuring that beneficial aerobic bacteria thrive in large numbers. Restorers have been successful also in reducing sediments and sludges, which collect at the bottom of lagoons and cause eutrification.

Restorers can be made from local materials and mass-produced to modular designs. The energy for driving the aeration systems can be drawn from a local utility or can be generated on the Restorers themselves using photovoltaics and wind power. Because the combined lagoon and Restorer system has a high biological momentum, it is excellent for handling wide variations in influent loading as well as power outages. The effluent from the lagoons, treated to UN WHO standards, can be used for irrigation. We believe the technology will provide simple, low cost and low maintenance treatment for developing countries, with the opportunity to re-use the treated water.

Bioshelters

Perhaps the most advanced expression of ecological design is the Bioshelter. Ecologically engineered systems are used to treat wastes, grow multiple food products, heat and cool the structures, and generate energy. The users of the Bioshelter take one another's outputs as their inputs to produce or manufacture their particular specialties. John and Nancy Jack Todd have described these ideas in their book, From Eco Cities to Living Machines.

A number of projects are currently in design and construction, which are "unplugged". These projects include such features as the collection and use of rainwater from roofs, the treatment of sewage in Living Machines™ with recycle to the toilets, nutrient capture for the irrigation of willows, which are coppiced for biomass energy generation and on-site electrical power generation, using wind, solar and fuel cells.

Conclusion

There are two fundamental ideas outlined in this paper. The working parts of natural wastewater treatment systems come from the wilderness. Nature is our mother and teacher. Also, instead of seeing wilderness as something other than and remote from industrial activity, Industrial Ecology asks us to design our facilities to be valuable and restorative members of the greater wilderness community. So wilderness is seen as a normal context for human activities, rather than as purely a remote sanctuary.

If we are to have a sustainable and restorative future, we need to apply principles of industrial ecology and ecological design to our industrial life. The application of natural systems to wastewater treatment is a necessary and positive step in this direction.