Tag: china’s air pollution

Towards a Cleaner Future: The Cactus-Inspired Oil Skin

???Oil spills are a very difficult problem. In addition to being catastrophic to the local environment, they are also incredibly difficult to clean up. After a spill occurs, some always stays on the surface while the rest forms heavy droplets and sink downwards, either becoming suspended in the water or falling to the bottom. Getting at these bits of the slick is difficult, and current methods are neither cost effective nor environmentally friendly themselves.

For example, the containment booms and chemical dispersants that BP used after the Deepwater Horizon spill were highly ineffective, as anyone who followed the news of the spill will recall. Because of that disaster, and others besides, numerous solutions have been proposed to deal with spills in the future – ranging from filters, to tiny submarines, and oil-eating bacteria.

artificial_cactusBut most recently, a group of researchers from the Chinese Academy of Sciences have suggested a nature-inspired solution. Their concept calls for droplet-collecting “skins” modeled after cactus plants. In the desert, these pants collect moisture when condensation covers the tips of their spines and then falls under its own weight to the base and gets absorbed by the plant.

Working from this, the Chinese researchers created their own “cactus skin” – artificial cone-shaped needles made of copper and coated in silicone that. When submerged in water, the half-millimeter spikes draw down oil droplets and collect them at the bottom. According to the researchers, the method is good for 99% of oil-water mixes and works with several types of oil.

chinese_academy_of_scienceThe research appeared in the latest issue of the journal Nature Communications. According to the paper:

Underwater, these structures mimic cacti and can capture micron-sized oil droplets and continuously transport them towards the base of the conical needles. Materials with this structure show obvious advantages in micron-sized oil collection with high continuity and high throughput.

The researchers think the device could also be used in the open air to remove fine droplets released with sprays. This way, they would be able to neutralize a good portion of oil released by malfunctioning rigs before it began polluting our oceans and waterways. On top of that, research at the Academy, specifically in the Institute of Chemistry, has revealed that this same concept might provide a solution to the problem of city pollution.

Between all of this, we could be seeing artificial cactuses in city environments very soon. Just not as potted plants and in the desert! And it does say much about our biomimetic future, where we are becoming increasingly dependent on solutions born of nature to solve our environmental problems.

Sources: fastcoexist.com, inhabitat.com, scmp.com

The Future is Here: The Air Scrubbing Skyscraper!

aircleaning_skyscraperAir pollution has always been a problem in urban centers. But with the massive industrialization and urban expansion taking place in some of the most heavily populated regions of the world (China and India being foremost), the issue of how to deal with increasing emissions is especially important. And more and more, researchers and environmentalists are considering options that hits air pollution where it lives.

Two such individuals are Danny Mui and Benjamin Sahagun, a pair of architects who have devised a rather novel concept for dealing with the thick layers of carbon dioxide pollution that are so common to major urban centers. In essence, it is a pair of buildings that scrub CO2 emissions from the air, and thus marries the concept of Carbon Capture technology to urban planning.

artificial_trees1Dubbed the CO2ngress Gateway Towers, the concept involves two crooked buildings that are outfitted with a filtration system. This system then feeds the captured CO2 to algae grown in the building which then converts into biofuels for use in vehicles. In this respect, it is not unlike the artificial tree concept designed by Klaus Lackner, director of the Lenfest Center for Sustainable Energy at Columbia University.

Much like these “trees”, the carbon capture technology involves using a entirely natural process to absorb CO2 from the air and then combine it with water, thus causing a chemical reaction that results in a fossil fuel precursor which can easily be converted. This fuel can then be consumed as gasoline or ethanol, thus giving people the ability to keep burning fossil fuels while they research cleaner, more sustainable sources of fuel.

aircleaning_skyscraper3Ultimately, the idea here is not to offer a be-all, end-all solution to the problem, but rather to buy the human race time to clean up its act. And by ensuring that carbon capture technology is available in large urban dwellings, they are looking to ensure that one of the many symptoms of urban sprawl – i.e. large urban dwellings – are part of the solution.

Said Mui and Sahagun on the Council on Tall Buildings and Urban Habitat (CTBUH) website:

The scrubbers are the first step in a process that generates fuel for a fleet of eco-friendly cars for building residents. The system raises public awareness of air pollution and its impact on the health of Chicagoans.

aircleaning_skyscraper1Aside from the scrubbers, the buildings boast some other impressive features to cut down on urban annoyances. These include the “double skin facade”- two layers of windows – that can cut down on outside traffic noise. In addition, the spaces on either side of the buildings’ central elevator core can be used as outdoor terraces for residents.

Apparently, Mui and Sahagun worked on the project while students at the Illinois Institute of Technology, where it earned them an honorable mention in the 2012 CTBUH student competition. According to Mui, they created the structure after the semester ended, but there are no immediate plans to build it.

aircleaning_skyscraper2However, given the growing interest in arcologies and urban structures that reduce our impact on the environment, it is likely to garner serious interest very soon. Especially in China, where air pollution is so severe that it causes up to 750,000 deaths from respiratory illness a year and cities are still growing, buildings like this one could easily become the stone that kills two birds.

Sources: factcoexist.com, bbc.com