Novel Wastewater Treatment Is New "It" Technology at Stanford

Can a balding, late-middle-aged researcher who's hawking a still-uncommercialized technology transform America's aging fleet of aerobic waste treatment plants?

The feat is a daunting Elon-Musk-sized task, but Stanford is betting big that Professor Perry McCarty's new Anaerobic Fluidized Bed Membrane Bioreactor can not only reduce the energy used to treat wastewater but actually send extra energy to the grid. And — surprise! — much of that new energy comes from an ignored and pungent brew of biosolids sitting in the aerobic treatment tanks.

McCarty, with typically understated self-assurance, claims his bioreactor solves a problem that hamstrings budget-constrained US mayors: traditional aerobic wastewater treatment uses 3.0% of the country's electricity, an expensive and depressing reality corroborated by the Energy-Positive Water Resource Recovery Report, which was released after a 2015 industry conference sponsored by the NSF, DOE, and EPA.

Even as his research fitfully progressed from bench-scale to pilot, McCarty has always claimed that up to half of his plant's energy would come from anaerobically produced biogas, and additional system-tweaks could squeeze out even more. However, his ultimate quest — and the Promised Land of a stable, brownout-free grid — is making the plant a net energy producer.

Bringing home the bacon

Fortunately for McCarty, the working group's report flags an approaching once-in-a-lifetime bonanza as cities replace old tank farms with new "Water Resource Recovery Facilities." This means mayors will eventually cough up $600 billion to support a nation-wide transformation, which includes moth-balling about 16,000 aerobic treatment plants, each squandering 57% of its energy to aerate oxy-hungry microorganisms breaking down sludge.

And McCarty, who promises to fully unleash wastewater's potential, has finally arrived or, more precisely, returned to the US carrying this revolutionary process in his Power Point presentation.

It should be noted that this former Clark, Tyler, and Stockholm Water Prize winner couldn't get research funding in the US. (ARPA-E grid-parity-solar-urgency, yes; Wastewater-e, sorry plumber, no) 

Unfortunately, advanced waste treatment research is underfunded in the US and usually pursued overseas. So McCarty followed the money to South Korea, where he partnered with professor Jaeho Bae, a former student, and spent five years developing his pilot-scale bioreactor.

An audience of his peers

During the Stanford professor's research update at the Clarke Prize Awards in 2015 (watch the video above), McCarty spoke to a supportive crowd filled with former students seeded throughout the global research ecosystem. He opened by reaffirming their credo for the resource-constrained 21st century:

In a world with limited resources, growing population and economic development, it's important that we look on all our former waste as resources.

That's hardy controversial, as today's aerobic plants continue to suck up more and more juice. In fact, this is such a pervasive flaw that even when aerobic treatment is hybridized with anaerobics for sludge digestion, only a small portion of the potential energy is captured. Dissolved energy-suffused organics are still removed — literally flushed out of the system.

Then McCarty bullet-pointed the advantages of his South Korean import. The wow-factor rushed through the audience when he explained that once the system started burning produced methane, it reduced energy use by over 80 percent compared to standard aerobic technology. Later, by burning dried biosolids, the plant could actually export electricity (read his paper).

He wanted colleagues and friends to know they finally had the goods. And wary bureaucrats would soon start cutting checks to migrate their lawn-watering, car-washing, leisurely-showering citizens to a more robust 21st century treatment technology.

Stanford incubator buzz

Unfortunately, although muni checks might soon be in the mail, McCarty's young technology teeters on the edge of venture capital's valley of death. The next evolution — an order of magnitude harder than tracking down research funds — is to entice risk-averse cities to embrace an update that relies on technology that is expensive and new, factors which are both big red flags.

But Stanford, sitting in the eye of the innovation hurricane known as Silicon Valley, knows a lot about marketing technology, even if most of its ephemeral and rapidly mutating software comes with so au courant hoodie-wearing twenty-somethings.

Tied to intractable atoms, molecules, and government bureaucrats, real-world infrastructure is a tougher sale — the ultimate slow-growth proposition.

Acknowledging the steep odds, two years ago Stanford broke ground on its $3 million William and Cloy Codiga Resource Recovery Center (CR2C) to help demo this remarkable technology and its developer. Although McCarty wears bifocals and a rumpled suit over a paunchy middle-aged body, Stanford wants to sell utilities on their sui generis techno-visionary of wastewater world.

This PR push is one of the center's primary goals, said organizer and engineering professor Richard Luthy, who wants to accelerate commercial development by demonstrating the new technologies with its fully staffed level-4 test-bed facility.

Schmoozing with the big boys

To help entice utilities to the Center, Sebastien Tilmans was brought in as operations director. He came with the perfect resume: a long history working at San Francisco's Oceanside Wastewater Treatment Plant. With his industry familiarity, he'll try to persuade anyone who can pull the trigger on a multimillion dollar project to kick the tires on McCarty's bioreactor and other innovations rolling out of the Center. “We know this is a transformational moment in our sector,” Tilmans said in a press release

Tilmans believes the (CR2C) has a vital role helping municipalities cope with the state's ongoing water crisis as they replace aging plants built in the 1970s. “We have a narrow window of opportunity to demonstrate the viability of alternatives to the 100-year-old paradigm,” he added.

If all goes well, the center will scale McCarty's technology to fit in portable units that can be sent to utilities for testing. Later, a project could be ready to scale up in four years. “It usually takes 10 years in this field to do something like this,” Tillmans said. 

The Center is also useful for other universities, private water and wastewater organizations, and corporations. Visiting researchers can use four test beds and different grades of wastewater to test new technologies. Then, once happy with the test data, they'll move into the field for a demonstration.

The Center is the fourth and largest Staged Anaerobic Fluidized Bed Membrane Bioreactor in the world, and the first time such a system is tested and demonstrated in the Western Hemisphere. The DOE,  the NSF, and the EPA have created a National Test Bed Facility Network to bring experts together to collaborate.

Watching the climate apocalypse approach, Tilmans says, “We need to work faster.” He hopes that In 10 years — or a little longer — he'll see the state recycling all wastewater in an energy-neutral way.

Will McCarty's technology make energy-intensive desalination less popular?

Images: Treatment plant, annabel; Stanford CGI, Stanford; South Korea group shot, McCarty; Bioreactor, McCarty; Ceremony, Stanford; Tilmans, Kate Chesley, Stanford