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E&E Exchange

Welcome to the Energy & Environment (E&E) Exchange, a blog dedicated to science and engineering topics that are (generally) related to energy and the environment. This blog is meant to encourage discussion about the challenges and possibilities surrounding sustainability through science and technology. The blog's owner, cheme_wordsmithy, is a former technical writer and engineering editor at IEEE GlobalSpec, the company that powers CR4.

Mr. Trash Wheel Cleans Up the Baltimore Waterfront

Posted March 16, 2017 2:12 PM by HUSH
Pathfinder Tags: baltimore harbor litter waterwheel

I don’t know much about Baltimore. I know that the city is somewhat famous for delicious crabs. I’ve also watched The Wire. Outside of that, I am Master Sergeant Schultz from Hogan’s Heroes.

What I do know is that the city of Baltimore has found a novel means to approach its marine litter issues. By 2021, the city has an unofficial plan to make its harbor safe for swimming and fishing. As with many city harbors it is heavily polluted with sewage and litter. Activism campaigns have helped curb the former. And since 2014, the city has employed a novel invention to help curtail that litter.

Mr. Trash Wheel is the invention of John Kellet, a sailor and engineer who worked in the harbor. After literally conceiving of the idea on cocktail napkin, Kellet approached the city of Baltimore about a water wheel that would sift floating debris from the harbor.

The idea is remarkably simple. Baltimore Harbor is fed by from the Patapsco River via Jones Falls. The current is the primary motive force for a waterwheel that powers two sets of conveyor belts. The first is a series of rotating tongs that lift solids out of the water and places refuse on the second conveyor, which delivers trash to a dumpster. A containment boom funnels trash toward the machine and the dumpster is on a separate float so it can be easily exchanged. For days with slower water current, solar panels provide the extra power.

The stats speak for themselves. Since it started operating, Mr. Trash Wheel has picked out 1,094,340 lb. of trash. This includes 379,000 bottles, almost 9 million cigarette butts and more than 600,000 bags. Most of this trash comes from upriver and is washed into creeks and the river with storms. The immense litter removal capabilities of Mr. Trash Wheel has spawned a second, larger trash waterwheel in Baltimore—Professor Trash Wheel.

By anthropomorphizing the trash wheels and giving them Twitter accounts, the Waterfront Partnership has seen popularity, and therefore pollution consciousness, rise. There is a live stream of the garbage collection as well. There is also hope for another trash wheel in the future, and the cities of Lombok, Panama City, Rio de Janeiro, Honolulu, Milwaukee, Atlanta and Denver are all considering similar projects with Kellet’s construction company.

I’d expect to see many more trash wheels like these two popping up in the next few years. With many urban cities trying to reclaim waterfront and green spaces, and the relatively low cost and effort of the trash wheels, they seem like a great, passive solution for the environment.

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Da Svedanya, Chernobyl

Posted December 21, 2016 10:43 AM by HUSH

As of last month, the site of Chernobyl Nuclear Power Plant looks nothing like it used to.

In the half-year after the infamous nuclear meltdown of reactor 4 at Chernobyl Nuclear Power Plant in April 1986, Soviet authorities hastily constructed the Shelter Object, which is the official name of the steel and concrete sarcophagus that contains more than 220 tons of highly radioactive isotopes and another 5,500 tons of debris and equipment, including 95% of the fuel that was present at the time of the meltdown.

The sarcophagus was constructed to protect people, namely those energy workers still running reactors 1,2 and 3, the “liquidators” who were tasked with the dealing with the meltdown’s aftermath, as well as the 50,000 people who had been evacuated from neighboring Pripyat, Ukraine, and were expected to one day be able to return home (spoiler alert: they weren’t). But to the Soviet Union, construction of the Shelter Object was also arguably an attempt to scrub the image of the destroyed reactor from the public eye and move on with its nuclear projects. Yet the Shelter Object was meant to be an interim solution from the beginning.

Due to extreme radioactivity at the site, the final assembly of the Shelter Object was completed by remotely-controlled 1980s robots, but this left many seams along the building’s exterior, risking contaminant leaks. The Shelter Object was also built on top of the existing reactor structures that were damaged in the initial steam explosion of the reactor. Should the roof or walls of reactor 4 collapse, large volumes of contaminated dust and debris would exit the quarantine zone.

In 2007, Ukraine awarded a €432 million (closer to €1 billion, today) contract to a French construction partnership named Novarka. More than 100 engineers worked on the design of what would temporarily become the largest mobile structure in the world. Named New Safe Confinement, the goals of the structure are to prevent future contaminant leaks even if a full or partial collapse of the Shelter Object occurred, as well as offer a means to isolate the dismantlement of Shelter Object and reactor 4.

Last November, the NSC slid into position, enveloping the Shelter Object over reactor 4, minus the reactor’s original chimney. The NSC is composed of 13 arches of tubular steel that give the building a final footprint of 656 ft. x 787 ft. x 361 ft. NSC is actually big enough to create its own weather inside, but engineers want to keep humidity below 40%. A 12 m gap exists between the roof and ceiling of the NSC, and the air in this space is heated several degrees above ambient and routed through desiccant dryers. Exposed steel work also has layers of polycarbonate. All of this adds up to a corrosion-free structure that will last more than 100 years.

The area immediately around reactor 4 is too radioactive to build near. Instead, NSC was constructed 600 m away, and because radiation exposure levels increase significantly above 30 m, all construction had to take place relatively close to the ground. So the ceiling roof of NSC was constructed first and propped up while workers completed the lower arch segments in sections. The flat side walls were mostly completed but left gaps for the Shelter Object to fit through. Once in place, workers will take spring and summer of 2017 finishing the side walls to create an air tight fit. In the last photo, the walls that will swing down to complete this are visible.

Moving the NSC from its build site to its final position took 15 days. At nearly 40,000 lb., one would expect a lot of energy is needed to move the NSC into place. Yet the archway was built on extra-large Teflon bearing links that slide along rails. Engineers were actually more worried about decelerating the NSC once it was in place or braking it from the effects of wind loads.

The NSC also had a secondary objective, which was to aid in the dismantling of the weakened Shelter Object roof and reactor walls, which must be done without ground labor. Two remote controlled cranes are suspended from gantries of the archway, both outfitted with interchangeable attachments of robotic arms, a core drill, concrete crusher and suction devices. These will also be able to transport scientists within the NSC within a shielded personnel carriage.

Images of Chernobyl have become easily identifiable and are typically offered as grim reminders of the potential of nuclear power. The first chapter of Chernobyl’s life provided jobs and power to a large portion of Ukraine. The second chapter ruined the lives of hundreds of thousands and badly damaged the reputation of nuclear energy forever. The third chapter, written by a corrupt government, was as much cover-up as remediation. Finally, more than 30 years after the reactor 4 meltdown, Chernobyl appears ready for its happy(ish) ending.

No one will forget about the Chernobyl disaster, but the imagery associated with it going forward is certainly going to be different.

28 comments; last comment on 12/27/2016
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France Will Ban Plastic Cutlery in 2020

Posted October 25, 2016 1:34 PM by Hannes
Pathfinder Tags: bioplastic france plastic

For the past several years, an all-out war has been silently waged between two opposing factions here at CR4 HQ: those who support the supply of plastic cutlery in the office and those who do not. Both sides have pretty valid points. The Pros enjoy the flexibility of walking into the break room and grabbing a fork if they forgot one at home, and the Cons raise the issues of office sustainability and the fact that plastics are now hanging around in landfills en masse.

This debate occurs throughout most of the world as well, of course. Billions of plastic cups end up in landfills every year. Plastic bags fill our streets and oceans, and are often ingested by sea life when mistaken for jellyfish. But certain jurisdictions have taken small steps against our plastic addiction. Plastic bag taxes and bans are becoming common around the world, for example.

France became the first country to introduce blanket legislation against plastic dishware in September, when it announced a total ban on sales of non-compostable plastic cutlery, dishes, and cups starting in 2020. The country’s had a busy year sustainability-wise: their ban on single-use “common” plastic bags went into effect July 1. France’s track record against the broader waste problem also includes a 2015 law mandating that large supermarkets donate unsold food to charities or animal feed producers rather than throwing it away.

But as far as the plastic dishware ban, it’s important to understand the terminology. According to AP coverage of the announcement, the law gives manufacturers until 2020 to ensure that “all disposable dishes sold in France are made of biologically sourced materials and can be composted.” Environmental advocates are often quick to point out that terms like “bioplastic” and “compostable” are often mere marketing buzzwords without a single meaning. In today’s market, “bio” often means the material will break down in a shorter time frame or break into tiny non-biodegradable plastic particles. These product naming conventions are rarely policed by legislation, although California became an exception to the norm in 2013 by declaring that “compostable” products must meet ASTM standards for the term.

Compostable plastics are still generally controversial, and their use varies widely. Even bioplastic cups are usually coated with a thin layer of “regular” plastic to keep drinks from leaking out. But cities such as San Francisco collect these with compost anyway, citing that there is typically no visible plastic after composting the cups. An interesting 2011 study found that those tiny plastic fragments actually contaminate the compost and become food for worms and insects. Other research has shown that these microplastic particles eventually get washed out and flow into bodies of water, potentially contaminating those as well.

France’s legislation has had a rough ride since its introduction. It’s faced obvious opposition from plastics and packaging manufacturers, some of whom are looking to sue the French government for violating EU laws supporting free movement of goods. Ecologists wanted the law to take effect next year, but the country’s Environment Minister postponed it over concerns that those facing financial struggles depend on plastic utensils and dishes. Whatever the outcome of the legislation, it’s a positive attempt at tweaking human impact on the environment.

Image credit: Shari's Berries / CC BY 2.0

44 comments; last comment on 11/03/2016
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Air Pollution Linked to Heart Disease

Posted June 02, 2016 7:00 AM by cheme_wordsmithy

It may seem obvious, but air pollution really does affect our health.

Many parts of the U.S. experienced some pretty hot days in the last couple weeks, and with it some warnings of ozone levels causing air quality concerns in metro areas like New York City and Long Island. This issue is a symptom of ambient air pollution that can have noticeable short-term health effects on people. It is also one reason I would tell my brother-in-law why I'm glad I'm not a city dweller.

But what about long-term exposure to lower levels of air pollutants, where the effects are harder to see?

Results from a study released May 24 show that exposure to even low levels of air pollution over time can affect cardiovascular health. The multi-ethnic study included 6,000 Americans monitored over a period of 10 years. CT scans were used to measure calcium deposits on the subjects' arteries over time, while ambient air samples were collected in their homes and neighborhoods and analyzed for concentrations of pollutants. The results, when analyzed, found a positive correlation between air pollution and accelerated atherosclerosis (hardening of the arteries), which leads to heart attacks.

The ambient air data included concentrations of PM2.5 (particulate matter less than 2.5 microns), nitrogen oxide and nitrogen dioxide (commonly referred to as NOx), and black carbon, all of which are common pollutants of concern found in ambient air. Models for pollution exposure were generated from thousands of sample collection points, state and federal data, traffic volumes, land use, weather, and nearby air pollution sources. PM2.5 and NOx and were found to have the strongest effects on heart health, the study found.

Much work has been done to prove the links between air pollution exposure and human health, but this study by the University of Washington is likely the most extensive ever done regarding heart disease, which is the leading cause of death worldwide. The scope of this study is impressive, almost as impressive as the magnitude of the implications it has. The data implies that the technology used to keep our air clean, from emission controls in cars to air pollution systems in industry, really is important. It implies that improving air quality will improve the quality of life for us and generations to come.

And to a much lesser extent, it gives me one more piece of ammunition in the city vs. country debate with my brother-in-law.

Source:

NewsBeat - UW Health Sciences

1 comments; last comment on 11/17/2016
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Just What (or Whom) Are We “Sustaining?”

Posted May 31, 2016 12:00 AM by Hannes

In a previous post I discussed the founders of the original Earth Day predicted that our 21st-century world would be devoid of any and all animal life, humans would rarely live past 45, and our ambient sunlight would be reduced by 50%. Obviously this post-apocalyptic vision did not come to pass, although maybe this fear-mongering frightened concerned citizens into giving the environmentalist movement a boost, or at least a few new members.

Near the heart of this movement is "sustainability," a buzzword that seems to grow in popularity as time goes on. It's nearly impossible to avoid: food companies are shamed for unsustainable fishing, large corporations tout their sustainable business practices, and institutions of higher education have sustainability officers. But while the mention of sustainability tends to evoke an environmentalist viewpoint, it also brings up the question: what or whom are we actually sustaining?

The general concept of sustainability is often described as the interplay between economy, society, and environment. The diagram on this page sums it up nicely: addressing any two of these three issues results in activities that are bearable for the environment or equitable for society. But the ideal is a midpoint between all three: sustainability.

Which of these three factors is the true focus of sustainability, however, is often muddled. The Brundtland Report, a 1987 UN report purporting to "re-examine the critical issues of environment and development," first defined sustainable development as "development that meets the needs of the present without compromising the ability of future generations to meet their own needs." While the report goes into further detail about factoring ecological considerations into all decision making, much of it focuses on sustaining ourselves, whether in the present or future. Clearly this definition leans toward economics, and to a lesser degree society.

In a thought-provoking 2015 blog post, biogeochemist and environmentalist Bill Schlesinger wrote that environmental "sustainability" is an oxymoron in that it concerns sustainable use of finite and therefore unsustainable resources such as petroleum and groundwater. He also points out that, even when we replant forests or develop sustainable fisheries, we tend to establish monocultural environments and ignore biodiversity. In other words, whereas these activities look good today, we're probably setting future up generations for more headaches in the future.

A few weeks ago Starbucks made news by issuing the first US corporate sustainability bond. According to a press release, the company "will use the net proceeds from the offering of $500 million in [notes] to enhance its sustainability programs around the coffee supply chain..." Craig Russell, EVP of Starbucks Global, is quoted as saying that "the longevity of the coffee industry is directly linked to the social, economic and environmental conditions of coffee communities around the world [...] This new sustainability bond offers a way for investors to better understand the work we are doing to help ensure that there is a future for farmers and our industry." In my humble opinion, subtracting the term "sustainability" from this offering renders it the same as any bond, in which the holder accrues a little interest for supporting Starbucks' business activities. Adding the term back in conveys that Starbucks cares about the little guys producing their product-a brand play. The press release later claims that the bond offering improves the effectiveness of coffee farming and advances the socioeconomic conditions of farmers, but without reasonably happy farmers there would be no coffee, and without coffee there would be no Starbucks. There are clearly two viewpoints as to the sustainability target.

The widespread use of and confusion over the term "sustainability" doesn't help the environmental cause. In an addendum to his blog, Schlesinger calls out the Dow Jones Sustainability Index (DJSI) for including energy companies such as Canadian Oil Sands Ltd., whose primary activity generates emissions at least 10% greater than conventional oil harvesting; requires on-site removal of not only trees and brush but also topsoil, clay, and other layers that impede an oil sand deposit; and may eventually concentrate heavy metals via the oil sands extraction process. But the DJSI has every right to include oil companies because it evaluates corporate sustainability, not strictly the environmental type. The Dow Jones evaluation of corporate sustainability focuses on long-term shareholder value and "managing risks and opportunities deriving from economic, social and environmental developments." They mention the Big Three sustainability factors, but their focus is on long-term business success. When evaluating corporate sustainability, even one of Canada's largest greenhouse gas producers can achieve high marks for their community investment and employee engagement, but maybe adding "Corporate" to the DJSI label would clear up some confusion.

It's not often clear whether "sustainability" refers to protecting business interests, the environment, or both. Stakeholders need to be careful about throwing the term around, especially when it can take on drastically different meanings whether used in industry, ecology, and even higher education.

Image credits: Johann Dréo / CC BY-SA 3.0 | CIAT / CC BY-SA 2.0

5 comments; last comment on 06/02/2016
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