ZooPoo: Algae bioregeneration and repurposing nutrients

by Mark Edwards

ature has used biological regeneration sustainably for eons because nature recycles and reuses nutrients over and over again. Bioremediation paired with bioregeneration operates on nature’s basic principle that there is no such thing as waste.

Your waste is my food.

Waste carbon and nutrients become the food energy that algae pair with solar energy to grow valuable bioproducts. The key to successfully following nature’s path requires thoughtfully integrating carbon and other nutrient pollution sources and syncing them with algae biofactories designed to capture nutrients and to grow bioproducts.

Rather than positioning nutrient recovery and reuse on a farm, where only a few people can see it, why not create a world class demonstration project at the zoo, where millions can share and see the experience? If we can do ZooPoo at the zoo, we can recover and repurpose energy and nutrients anywhere.

Futurists have positioned algae bioremediation and bioregeneration for NASA and DARPA’s 100-Year Starship project. Algae are proposed to provide food, life-support, waste cycling, green chemicals, bioenergy, and building materials. Algae are also recommended to make the medicines necessary for 100 years of life in space. ZooPoo provides a more down-to-earth opportunity for algae biosolutions.

The intriguing positioning of algae cycling and reuse in both a long-voyage spaceship and a zoo creates an important question. NASA calculated that six liters of algae water will produce 600 grams of food, (540 grams is 2500 calories, an average daily food requirement), 600 liters of oxygen, and consume 720 liters of CO₂. Is there any other organism on earth that can sustain both a starship and a zoo?

Imagine that your zoo becomes the world’s first EcoZoo, and demonstrates nature’s preferred mode of energy storage and harvest – green solar energy in rich algae biomass. Nature’s first and simplest energy system, algae, uses only sunshine, wastewater and surplus CO2 to recycle and reuse ZooPoo to produce clean, sustainable, carbon neutral food, feed, energy, fertilizer and freshwater.

ZooPoo enables the zoo to move towards a net zero:

• Carbon footprint — no net carbon dioxide emission.
• Freshwater footprint — no net freshwater consumption.
• Fossil fuels footprint — no net fossil fuels consumption.
• Fossil nutrient footprint — no net fossil nutrient consumption.

The ZooPoo exhibit shows visitors how farmers can grow healthy foods and bioproducts while protecting all the animals and plants on earth from the overconsumption, waste and pollution associated with industrial agriculture.

Discussions with zoo directors and managers revealed that some zoos pay more to manage ZooPoo, botanical and animal wastes, than their animal feed. In the name of ecological safety, bureaucrats have levied layers of protections, e.g. inspectors from various bureaus, on zoos to monitor their waste management. California imposes no less than five agencies to monitor zoo waste streams.

Zoo waste management has become a major cost because the current process is extremely labor and energy intensive. Zoos must carefully gather their waste products and transport them to a holding facility where no discards can leach into the ground – even if it rains. Typically, the poo (animal manure) must be covered to avoid unpleasant odors. After inspection, the manure wastes are loaded into trucks and transported long distances to an approved waste dump. In addition to all these costs, some local or state governments add fees by weight to waste that go to dumps. Incredibly, the zoo must go to great expense to manage ZooPoo and then forfeits the entire poo value.

ZooPoo contains roughly 60% of the energy originally in the plants eaten by zoo animals. Elephant poo contains about 90% of the original plant energy because, while elephants have the biggest appetites of all zoo animals, they have the lowest energy and nutrient absorption. Elephants are enormous, rich poo factories. Zoos provide an excellent model for nutrient cycling because ZooPoo retains 80% of the nutrients originally in the plants eaten by zoo animals. Zoos currently lose both the energetic and nutritive value in animal and botanical wastes.

Each zoo dumps a gold mine of rich energy and recoverable nutrients into already overfilled waste dumps. ZooPoo bioremediation and bioregeneration can transform a huge zoo cost to a profit center. Even better, the process can create a superb destination for ecotourism and learning center.

Eco-smart states, such as California, Massachusetts, Oregon, and Washington have passed disposal bans on certain products, including yard materials and botanical waste. Those wastes are removed by vehicles on a fee for service basis. Experience shows there is no effective practical way to enforce a recycling goal. However, public officials are able to enforce disposal bans. As a political strategy, pursuing disposal bans has a better chance of success with public acceptance than attempting to pass a comprehensive state or federal solid waste plan.

Many countries in Europe and central America have passed laws to completely prohibit dumping. The motivation for these dumping bans is simple; countries have run out of land acceptable for waste disposal. Spain, Denmark, Canada and other leading green countries are finding surprisingly profitable business in waste-to-energy technologies, including gasification and gas plasma.

Conventional waste-to-energy plants that use mass-burn incineration can convert one ton of MSW, (municipal solid waste) into about 550 kilowatt-hours of electricity. Gasification technology is about twice as efficient with feedstock and uses one ton of MSW to produce about 1,000 kilowatt-hours (kWh) of electricity. Plasma gasification offers similar efficiencies and can be used to convert carbon-containing materials to synthesis gas that can be used to generate power and other useful products. Gas plasma provides safe waste-to-energy solutions for hazardous, biomedical, hospital and chemical materials. Anaerobic digestion (see discussion below), of wet organic wastes can generate 300 to 1,000 kWh per ton while producing digestate as a valuable byproduct that can be composted as a soil amendment or further processed into solid and liquid fertilizer for growing beneficial crops.

Mass-burn waste-to-energy technologies create two pollutive emissions, incineration flue gasses and the biochar residual in the combustion chamber. The flue gasses can be remediated by algae to produce more biomass. The biochar serves to safely sequester potential pollutants in a slow release soil amendment to support field crops.

The ZooPoo exhibit architecture will demonstrate the value of nutrient cycling. Many zoo guests recycle their organic material at home and their grocery bags, so they are already aware of the recycle-reuse value proposition. The primary nutrient cycling takeaway is the ability to monetize waste and pollution. ZooPoo transforms the substantial zoo waste management cost into a profit center. Target market guests, those who currently pay to burn or bury their wastes, include:

• Farmers, who will be able to realize value from animal and plant wastes and moderate pollution and waste.
• Municipal waste facilities, that will be able to create value from human waste streams.
• Community (food waste, garden and trash) waste facilities, that will create value from recyclable trash and garden botanicals.
• Power and cement plants and manufacturers, that will create value from their surplus CO₂ while avoiding emissions.
• Citizens who desire to learn how to minimize their waste streams and ecological footprint.
• Children who wish to convey the message of conservation and renewal to their peers and parents.
• Churches that desire to convey green and sustainable lifestyles to their communities.
• Schools that want to engage students in sustainable systems.
• Green and environmental social networks that want to see ecologically responsible production of food, feed, and freshwater.
• Zoo visitors interested in food and energy security by reclaiming and recycling surplus inputs that are affordable and, unlike fossil resources, will not run out.
• Visitors committed to global stewardship by moderating pollution while producing valuable bioproducts that cycle or store rather than release carbon. If only a fraction of people — 20% — made small, environmentally beneficial changes, such as switching furnace filters, using low energy light bulbs, or driving less aggressively, overall energy consumption would drop by up to 20%.”
• Educators in sustainable and affordable food and energy (SAFE) production, that creates a positive ecological footprint.

ZooPoo can be designed to convey mission critical solutions for social, economic and environmental challenges.