The new oil is the old black.
While mining conglomerates and big oil scour the world's oceans and deserts for uncharted deposits of natural resources, a handful of companies are looking closer to home.
Wastewater and all of the other stuff that goes down the drain is a veritable treasure trove of select raw materials, according to some academics and startups. Economically, it's strong argument. Municipalities globally spend billions on treating wastewater and animal waste and in return get very little out of the process. Waste also injects methane and nitrogen into the environment, escalating costs. By turning waste streams into revenue streams, bond measures become far easier to pass. And if anyone wants to borrow my slogan – "Life's A Bowl Of..." – let me know.
It also offers a way out of the looming water crisis. Singapore already recycles human wastewater under the NEWater program as a way to wean itself off of water imports from Malaysia. So what do you do?
1. Water the Lawn and Mine It: Mark Shannon, Director of the NSF STC WaterCAMPWS at the University of Illinois is raising funds to build a prototype anaerobic digester that will convert sewage into re-useable water, methane and a sludge of minerals that can be sold to manufacturers or brick makers.
"The dirtier, the better," Shannon said.
The system in part works because humans are not efficient processors of chemicals: A lot of what we ingest comes out. Chicago's wastewater now contains about 6 mega joules of energy for every cubic meter. It takes about 9 mega joules to purify it with chemicals, leading to an energy loss of 15 mega joules of energy for every cubic meter.
If you harvested for methane, the city could harvest 5 mega joules per cubic meter, leading to a net energy gain from the sewer. Chicago has a sewage outflow of 283 cubic meters a second.
The minerals recovered include magnesium, boron, fly ash and lithium.
"The whole concept of recycled water is going to happen. It is inevitable," said Spike Narayan, functional manager, science & technology, at IBM's Almaden Research Center, which is developing materials for purification membranes, in a recent interview.
2. Dig out the Nutrients: Ostara Nutrient Recovery Technologies. extracts phosphorous and other nutrients from wastewater and then recycles it into fertilizer. Ostara estimates that approximately 200 plants in North America and several hundred plants in Europe and the rest of the world are candidates for the technology.
The company has been running a plant in Edmonton, Alberta since 2007 and just opened one in Oregon. The reactor extracts more than 75 percent of the phosphorus and 15 percent of the ammonia from a sewage sludge stream of 500,000 litres per day. The resulting mixture is used to make roughly 500 kilograms of Crystal Green. That's not a powdered drink mix – that's the fertilizer.
3. Make Fish Food: Oberon FMR harvests bacteria from wastewater streams at food processing plants and turns it into feed for fish farms.
"We transform waste products in food and beverage manufacturing into high-quality feed grade," said CEO Randy Swenson earlier this year. In a test with growing tilapia, the fish grew 43 percent larger after eight weeks with Oberon's feed than with regular feed, he said. The next time you order fish tacos, bring this topic up.
4. Dip It in Iron: Ze-Gen takes construction and municipal waste, dips it into vats of boiling, red-hot iron, and converts it to carbon monoxide and hydrogen that can be burnt in lieu of natural gas. Cities often pay $30 a ton for landfill and 400 billion tons of waste gets produced every year. The process reduces the amount of methane that leaks from landfill and they have the whole "I am Iron Man" thing. While it's mostly a landfill company, the funding ($28 million and counting) and progress it has made means Ze-Gen is an important factor in this market.
"To the extent that biosolids can be safely re-purposed as fertilizer, this is likely the best use of this waste stream. But for urban centers and areas with limited demand for fertilizers, a more efficient method of unlocking biosolids' energy content could be the next best option," the company wrote on its blog.
5. Produce Urea: Urea, a substance that gets its name because of its presence in urine, is one of the world's most prevalent industrial chemicals. It gets used in plastics and in engines to reduce emissions. But, weirdly, it's artificially made. Chemical manufacturers produce it by cracking methane.
Agroplast, a small company in Denmark, has created a design for a feedlot that will automatically collect the urine, separates out the urea, and then prepare it for a useful life beyond the farm. The collector lets waste from pigs fall through a grate. Once beneath the grate, the urine is rapidly separated from the manure. If the separation isn't accomplished quickly, the urine turns to ammonia. Ammonia is actually the source of the terrible smells on farm, so there's another benefit.
A few universities in the U.S. are working on similar ideas.
6. Power Cellphones: Professor Derek Lovley has been working with Geobacter, a species of bacteria, since he discovered it living in mud from the bottom of the Potomac River about 20 years ago. For most of that time, it was prized for "breathing in" iron and other substances, which made it useful for cleaning wastewater or earth of toxic metals.
But in more recent years, Lovley and other researchers have been studying Geobacter's habit of generating electrons as a byproduct of its respiration process in anaerobic environments. Thus, the bacteria one day could be used to power microbial fuel cells.
7. Generate Hydroelectric Power: Technically, Rentricity isn't deriving power from sewage. Instead, it has created a micro-hydro unit that harnesses power from the pressurized water streams created by municipal water agencies to deliver water or handle storm water. Think of it as taking advantage of a byproduct of the water system. In a similar vein, HydroVolts in Washington State has a tidal turbine designed for irrigation ditches.
8. Make Coal: Carbonscape out of New Zealand microwaves and compresses organic matter – wood chips, corn stalks and even sewage – into eco-coal. It burns like regular coal, but the carbon doesn't come deep from the ground. Renewable Fuel Technology, meanwhile, has devised a modified version of the Fischer-Tropsch process to convert organic matter into coal. Organic matter gets converted to syngas first.
9. Produce Pipeline-Grade Methane: BioEnergy Solutions builds, maintains and operates the anaerobic manure digesters that convert manure into methane. The process isn't entirely green – carbon dioxide in the gas from the manure has to be burned off before the methane can be sent down a pipeline – but it does eliminate many of the hazards associated with manure. Revenue can also be generated through carbon credits and selling the solids as cow beds or fodder for, maybe some day, organic flooring or building materials.
So far, it has 30 dairies under 10-year supply contracts and a fixed price contract for gas with Pacific Gas and Electric. In all, there are 70,000 cows contributing gas. There are 1.8 million cows in the California Central Valley. The problem? It's a bit capital intensive. Digesters are essentially really big ponds. It takes about 20,000 cows at each location to break even, said CEO David Albers. Others, such as Microgy, are mining the same field.
10. Run Your Car: BioPetrol exploits Fischer-Tropsch to produce a synthetic version of petroleum. Gas and biochar are also byproducts. The Fischer-Tropsch system was originally invented to turn coal into oil (also known as the Hans and Franz process after Hans Fischer and Franz Tropsch) in the 1920s. It can be expensive because of all of the processing. Only two regimes – the Third Reich and Apartheid-era South Africa – heavily relied on it and they did so because of trade embargoes.
11. Make Water Bottles: Think of this more as microbial sewage. Ireland's Bioplastech (out of University of College Dublin) has devised a way to recycle old plastic bottles and containers with microorganisms. The bugs eat a cooked down version of a plastic bottle and metabolize it into a new, saleable version of plastic.