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Wednesday, July 9, 2014

Oklahoma earthquakes induced by wastewater injection by disposal wells, study finds

House damage in central Oklahoma from the magnitude 5.6 earthquake on Nov. 6, 2011.

Credit: Brian Sherrod, USGS

The dramatic increase in earthquakes in central Oklahoma since 2009 is likely attributable to subsurface wastewater injection at just a handful of disposal wells, finds a new study to be published in the journal Science on July 3, 2014.

The research team was led by Katie Keranen, professor of geophysics at Cornell University, who says Oklahoma earthquakes constitute nearly half of all central and eastern U.S. seismicity from 2008 to 2013, many occurring in areas of high-rate water disposal.

"Induced seismicity is one of the primary challenges for expanded shale gas and unconventional hydrocarbon development. Our results provide insight into the process by which the earthquakes are induced and suggest that adherence to standard best practices may substantially reduce the risk of inducing seismicity," said Keranen. "The best practices include avoiding wastewater disposal near major faults and the use of appropriate monitoring and mitigation strategies."

The study also concluded:

  • Four of the highest-volume disposal wells in Oklahoma (~0.05% of wells) are capable of triggering ~20% of recent central U.S. earthquakes in a swarm covering nearly 2,000 square kilometers, as shown by analysis of modeled pore pressure increase at relocated earthquake hypocenters.
  • Earthquakes are induced at distances over 30 km from the disposal wells. These distances are far beyond existing criteria of 5 km from the well for diagnosis of induced earthquakes.
  • The area of increased pressure related to these wells continually expands, increasing the probability of encountering a larger fault and thus increasing the risk of triggering a higher-magnitude earthquake.

"Earthquake and subsurface pressure monitoring should be routinely conducted in regions of wastewater disposal and all data from those should be publicly accessible. This should also include detailed monitoring and reporting of pumping volumes and pressures," said Keranen. 'In many states the data are more difficult to obtain than for Oklahoma; databases should be standardized nationally. Independent quality assurance checks would increase confidence. "

Source: The above story is based on materials provided by Cornell University.

Journal Reference: K. M. Keranen, M. Weingarten, G. A. Abers, B. A. Bekins, and S. Ge. Sharp increase in central Oklahoma seismicity since 2008 induced by massive wastewater injection. Science, 3 July 2014 DOI: 10.1126/science.1255802

Tuesday, July 1, 2014

World's First Industrial-Scale Waste-to-Biofuels Facility

By Ben Coxworth | June 20, 2014

NYCU 20140630

Thanks to its extensive composting and recycling facilities, the city of Edmonton, Canada is already diverting approximately 60 percent of its municipal waste from the landfill. That figure is expected to rise to 90 percent, however, once the city's new Waste-to-Biofuels and Chemicals Facility starts converting garbage (that can't be composted or recycled) into methanol and ethanol. It's the world's first such plant to operate on an industrial scale, and we recently got a guided tour of the place.

The process begins with garbage trucks dumping their loads on the tipping floor at the Integrated Processing and Transfer Facility. The trash is manually and mechanically sorted, with things like appliances being set aside for electronic parts recycling and e-waste disposal, while organic matter heads off to the Composting Facility.

Recyclable materials are already pre-separated by citizens as part of the city's blue bag program. They avoid the garbage stream entirely, going straight to the Materials Recovery Facility for recycling.

Soon, though, high-carbon materials such as wood, fabric and discarded plastic will be getting shredded into Refuse Derived Fuel (RDF), also known as "garbage fluff." It will be transferred to the Waste-to-Biofuels and Chemicals Facility, which is owned and operated by Enerkem Alberta Biofuels.

There, it will be heated in a low-oxygen atmosphere. This will cause its chemical bonds to break (without the material actually burning), releasing their carbon and hydrogen content to form what's known as syngas. This will in turn be cleaned up and converted into chemical products and biofuels – such as methanol and ethanol.

The Waste-to-Biofuels and Chemicals Facility is scheduled to go online in the next several weeks. It is ultimately expected to convert 100,000 tonnes (110,231 tons) of municipal solid waste into 38 million liters (10 million gallons) of biofuels and chemicals annually.

You can see our video tour of the facility below, conducted by the Edmonton Waste Management Centre's Education Programs Co-ordinator, Garry Spotowski. There are also photos of the process in the gallery.

The video can be viewed at: https://www.youtube.com/watch?v=LKKweSAm1Ks

Source: http://www.gizmag.com/edmonton-waste-to-biofuels-facility-video-tour/32630/

Wednesday, June 18, 2014

Magnets Mean Your New Refrigerator Will Make History

June 10th, 2014 | by Michael Keller

Coming soon to a kitchen near you - magnets in your refrigerator. And we're not talking about slapping your kid's artwork inside the fridge next to the milk and butter.

It's the next generation of residential food and drink cooling, and it's powered by magnets. Gone will be the almost century-old unit in your kitchen that uses a heat-transfer process based on liquid refrigerants called vapor compression refrigeration. Condensers and refrigerants will be replaced with magnets and special alloys that get hot and cold based on their proximity to magnetic fields. The technology could also be used for air-conditioning.

Magnetic refrigeration, proponents say, is a rapidly approaching technology that will amount to a revolution in domestic energy use.

"It's the equivalent to a gas-powered car moving to electric - that's the kind of leap we're making in refrigeration," said Ed Vineyard, a senior researcher at the U.S. Department of Energy's Oak Ridge National Laboratory. Vineyard's Building Technologies Program has teamed up with GE to bring magnetic refrigeration to the public in around five years.

The idea behind refrigerators and air conditioners is all the same. In their broadest sense, they are heat pumps - devices that take heat energy from inside your refrigerator box or room and move it outside. Removing this energy makes the temperature go down.

In most contemporary home and commercial refrigeration systems, mechanical work compresses and expands a liquid refrigerant. The pressure drop associated with expansion lowers the temperature of the refrigerant, which then cools air blown over it by a fan into the refrigerator box or the cooled room. In magnetic refrigeration systems, the compressor is replaced with magnetic fields that interact with solid refrigerants and the water-based cooling fluid. Changing the strength of magnetic fields alters how much heat is pulled away from the refrigerator box.

Along with this refrigerator revolution comes a dramatic drop in the amount of energy you need to cool your cucumbers and cantaloupes. ORNL says magnetic refrigeration "is a promising alternative to the vapor compression systems used in today's appliances" that could theoretically drop energy consumption by 25 percent compared to current technology. Those liquid refrigerant chemicals that can be damaging to the environment and hard to recycle at the end of a refrigerator's life are also being replaced by cheaper water-based fluid.

Oak Ridge National Laboratory's Ayyoud Momen works on the team's "breadboard" prototype refrigerator-freezer: a flexible platform used to evaluate material compatibility and to analyze components including the magnet, generators, motor, pump, heat exchangers, plumbing and leakless rotating valve. Courtesy ORNL.

Developers expect the new refrigerators to cost a bit more than vapor compression models, but buyers should see savings through spending less on electricity over the long term. If the technology is adopted broadly, it could mean major electricity savings on the national scale. Besides savings from more efficient refrigerators, magnetic cooling would lower electricity use in heating, ventilation and air-conditioning equipment, which accounts for around 60 percent of the average household's energy use.

Source: http://txchnologist.com/post/88367608863/magnets-mean-your-new-refrigerator-will-make-history

Tuesday, June 17, 2014

Wastewater That Cleans Itself Results in More Water, Less Sludge

The treatment process in progress, using chemicals naturally abundant in wastewater to clean itself.

Using wastewater to clean itself is the premise of new Australian technology that relies on the formation of compounds called hydrotalicites, and which results in less sludge than traditional water treatment with lime. In one test, the equivalent of 20 Olympic-sized swimming pools of wastewater were treated, with final sludge reductions of up to 90 percent.

Hydrotalicites are layered crystal structures of carbonates, magnesium, and aluminum, and importantly, they can trap impurities within themselves.

By chemically manipulating these elements "naturally" present in wastewater in high concentrations, researchers at CSIRO, Australia's science agency, caused the formation of these hydrotalicites. This process occurs as the concentration of magnesium and aluminum is altered and the pH of the water raised. As the crystals form, trapped within them are numerous other waste substances – in the test case, those included radium, rare earth elements, anions and transition metals.

The resulting mixture can be easily centrifuged to separate out the sludge, which there is less of due to its higher concentration and smaller volume of water mixed in. The now-concentrated sludge can be theoretically "mined" again to recover some of the metals and minerals from the mixture. The water can be more efficiently purified further, if needed, and reused by the facility.

The wastewater sludge that remains after treated water is removed from a hydrotalcite treatment.

With the reduction in volume of sludge comes greater ease and lower costs in transporting and disposing of it.

The process is being developed for licensing by Virtual Curtain Limited.

In the video http://www.youtube.com/watch?feature=player_embedded&v=W-9nGeDxt1c, Dr. Grant Douglas, a senior researcher at CSIRO, presents the process and benefits of using wastewater as a template to clean itself.

Source: CSIRO

Thursday, May 22, 2014

Responding to Oil Spills in the U.S. Arctic Marine Environment (2014)

A new video from the National Research Council explores the recent report, Responding to Oil Spills in the U.S. Arctic Marine Environment.

As the Arctic warms and sea ice retreats, Arctic waters are becoming busier and the risk of serious oil spill is increasing. This video describes the suite of technologies, infrastructure and research needed to support effective oil spill response in the challenging Arctic environment.

Find the report and related resources here, including a webinar, report in brief and downloadable maps.

image of video

Source: Division on Earth & Life Studies.

Monday, May 5, 2014

Water-Testing Pills Draw on Breath-Freshening Tech


A water sample being added to a vial for testing, using one of the new pills.

Wondering if it's safe to drink the water from your remote village's well? Typically, the only way of finding out involves sending a sample of that water off to a lab, or using testing agents that must be shipped in and kept on dry ice. Now, however, scientists from Canada's McMaster University have developed simple pills that can do the job – and they were inspired by breath-freshening strips.

PhD student Sana Jahanshahi-Anbuhi, who is one of the team members, first came up with the idea when he saw some of the strips while grocery shopping. Breath strips are made with an edible polymer called pullulan, that forms a protective solid shell when dry, but that dissolves when exposed to liquid.

He surmised that pullulan could also be used to protect the agents used to test water for pathogens. Those agents can deteriorate within hours of exposure to oxygen and temperature changes, which is why they must ordinarily be shipped and stored sealed in vials, and at low temperatures.

As it turns out, Jahanshahi-Anbuhi was onto something. The resulting pills are cheap to produce, can be kept at room temperature for months at a time, and are simply added to a sample of the local water when testing is required. If the sample changes color after being shaken, it means that the water contains harmful bacteria, pesticides, heavy metals, or other pollutants.

While the pills could be useful to people such as hikers, they should be particularly helpful to people in developing nations, that lack easy access to decently-equipped labs. It is also hoped that the technology could be applied to things like food packaging that changes color if the contents are spoiled.

A paper on the research was recently published in the journal Angewandte Chemie.

Source: McMaster University

Thursday, May 1, 2014

Wonder-Material Graphene Could be Dangerous to Humans and the Environment


Jacob D Lanphere, a Ph.D. student at UC Riverside, holds a sample of graphene oxide.

People have been waiting for some time to write a headline along the lines of "scientists discover thing that graphene is not amazing at" ... and here it is. Everybody's favorite nanomaterial may have a plethora of near-magical properties, but as it turns out, it could also be bad for the environment – and bad for you, too.

It's easy to get carried away when you start talking about graphene. Comprised of single atom thick layers of carbon, graphene is incredibly light, incredibly strong, extremely flexible and highly conductive both of heat and electricity. Its properties hold the promise of outright technological revolution in so many fields that it has been called a wonder material.

But it's only been 10 years since graphene was first isolated in the laboratory, and as researchers and industries scramble to bring graphene out of the lab and into a vast range of commercial applications, far less money is being spent examining its potential negative effects.

Two recent studies give us a less than rosy angle. In the first, a team of biologists, engineers and material scientists at Brown University examined graphene's potential toxicity in human cells. They found that the jagged edges of graphene nanoparticles, super sharp and super strong, easily pierced through cell membranes in human lung, skin and immune cells, suggesting the potential to do serious damage in humans and other animals.

"These materials can be inhaled unintentionally, or they may be intentionally injected or implanted as components of new biomedical technologies," said Robert Hurt, professor of engineering and one of the study's authors. "So we want to understand how they interact with cells once inside the body."

Another study by a team from University of California, Riverside's Bourns College of Engineering examined how graphene oxide nanoparticles might interact with the environment if they found their way into surface or ground water sources.

The team found that in groundwater sources, where there's little organic material and the water has a higher degree of hardness, graphene oxide nanoparticles tended to become less stable and would eventually settle out or be removed in sub-surface environments.

But in surface water such as lakes or rivers, where there's more organic material and less hardness, the particles stayed much more stable and showed a tendency to travel further, particularly under the surface.

So a spill of these kinds of nanoparticles would appear to have the potential to cause harm to organic matter, plants, fish, animals, and humans. The affected area could be quick to spread, and could take some time to become safe again.

"The situation today is similar to where we were with chemicals and pharmaceuticals 30 years ago," said the paper's co-author Jacob D. Lanphere. "We just don't know much about what happens when these engineered nanomaterials get into the ground or water. So we have to be proactive so we have the data available to promote sustainable applications of this technology in the future."

At this stage, the Material Safety Data Sheet governing the industrial use of graphene is incomplete. It's listed as a potential irritant of skin and eyes, and potentially hazardous to breathe in or ingest. No information is available on whether it has carcinogenic effects or potential developmental toxicity.

But researchers from the first study point out that this is a material in its infancy, and as a man-made material, there are opportunities at this early stage to examine and understand the potential harmful properties of graphene and try to engineer them out. We've got a few years yet before graphene really starts being a big presence in our lives, so the challenge is set to work out how to make it as safe as possible for ourselves and our planet.

Source: http://ucrtoday.ucr.edu/22044