Earth Wise

A look at our changing environment.

You are here: Home / Archives for recycling

recycling

Repurposing used tires

By Leave a Comment

Every year, millions of tires from cars and trucks end up in landfills.  Just in the U.S., more than 270 million tires were scrapped in 2021 and more than 50 million of them ended up in landfills.  Discarded tires take up huge amounts of space but, more importantly, create environmental hazards.  They leach chemicals into the environment and are a serious fire hazard.

Some tires are chemically recycled via pyrolysis, which is a high-temperature process to decompose the materials in the tire.  But that process introduces harmful byproducts like benzene and dioxins. 

Researchers at the University of North Carolina Chapel Hill have introduced a new chemical method for breaking down rubber waste.  The process transforms discarded rubber into valuable precursors for epoxy resins.

Rubber – either natural rubber or the synthetic kind used in tires – is made of polymers cross-linked together to form a tough, flexible, and durable material.  These very desirable properties make it difficult to break down rubber.

The new research has led to a two-step chemical process that breaks down the rubber into functional materials that be used to produce epoxy resins.  The method does not require extremely high temperatures, uses aqueous media, and takes only six hours.   It represents an efficient, scalable solution for repurposing rubber waste which, even as many other aspects of motor vehicle are changing for the better, remains a continuing environmental problem associated with driving.

This new research marks a significant step towards greener recycling technologies.

**********

Web Links

A Cleaner Future for Tires: Scientists Pioneer Chemical Process to Repurpose Rubber Waste

Photo, posted May 5, 2011, courtesy of TireZoo via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Plastic from food waste

By Leave a Comment

Plastic waste management is a complicated business.  Most methods of recycling or breaking down plastic are costly and harmful to the environment.  The most common biodegradable alternatives – like paper straws – are less than ideal replacements.

There are many approaches to creating biodegradable plastics using feedstocks like seaweed, sugarcane, and other plant matter.  However, the resulting plastics often fall short compared with conventional petroleum-based plastics.

One type of bioplastic that is gaining popularity is polyhydroxyalkanoates, or PHA.  PHA is a plastic produced by microorganisms.  It is fully compostable or biodegradable but in other ways but looks, feels, and functions like regular plastic but without the environmental drawbacks.

PHA can be made using bacterial fermentation of a variety of feedstocks such as vegetable oils, sugars, starches, and even methane and wastewater.

Researchers at a startup from the University of Waterloo in Canada called MetaCycler BioInnovations have developed a process for producing PHA based on bacteria that has been engineered to convert waste from milk and cheese production.  This solution upcycles waste from the dairy industry into cost-effective, sustainable bio-based plastics. 

PHAs can be tailored to have a wide range of properties ranging from being rigid and tough to being quite flexible.  Therefore, they can be suitable for many applications including packaging, agricultural films, and consumer goods. 

The Waterloo technology is a way to tackle the problems of both food waste and plastic pollution with one solution.

**********

Web Links

Turning food waste into a new bioplastic

Photo, posted December 10, 2017, courtesy of Leonard J Matthews via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Recycling lithium-ion batteries

By Leave a Comment

Lithium-ion batteries are used to power computers and cellphones and, increasingly, vehicles.  The batteries contain lithium as well as various other valuable metals such as nickel, cobalt, copper, and manganese.  Like other batteries, lithium-ion batteries have a finite lifetime before they can no longer perform their intended function.

Recycling lithium-ion batteries to recover their critical metals is an alternative to mining those metals.  A recent study by Stanford University analyzed the environmental impact of obtaining those metals using lithium-ion battery recycling compared with mining.  They found that the recycling process is associated with less than half of the greenhouse gas emissions of conventional mining.  The process uses about one-fourth of the water and energy of mining new metals.  North America’s largest industrial-scale lithium-ion battery recycling facility is Redwood Materials, located in Nevada, which uses a clean energy mix that includes hydropower, geothermal, and solar power.

These calculated advantages are associated with recycling batteries that have been in use.  The advantages are even greater for recycling scrap:  defective material from battery manufacturers.

The advantages of recycling are dependent on the sources of electricity at the recycling plant and the availability of fresh water. 

At present, the U.S. recycles about half of its available lithium-ion batteries.  By comparison, 99% of lead-acid batteries (like those found in cars and trucks) have been recycled for decades.  As the supply of used lithium-ion batteries continues to increase, it is important for the availability of industrial-scale battery recycling to keep pace. 

**********

Web Links

Recycling lithium-ion batteries delivers significant environmental benefits

Photo, posted May 7, 2020, courtesy of Mark Vletter via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Curbing food waste

By Leave a Comment

According to the U.S. Department of Agriculture, as much as 40% of the food supply in the United States is wasted.  In fact, Americans generate more food waste than all but two countries.

To address this problem, the federal government announced a goal nearly a decade ago to cut food waste in half by 2030 compared to 2016 levels.  Doing so would bring food waste down to approximately 164 pounds per person annually.

However, according to a new study led by researchers from the University of California – Davis, since 2016, per capita food waste has actually increased instead of decreasing. 

The study, which was recently published in the journal Nature Food, looked at how state policies align with federal targets.  The research team found that state policies focus more on recycling methods, such as composting and anaerobic digestion, rather than on prevention and rescue strategies, like food donations or repurposing food for animal feed.

In 2021, the EPA revised its definition of food waste to no longer include recycling methods.  But when food is wasted, the resources used to grow the food, including energy, water, and fertilizer, are also wasted. 

In the study, the researchers analyzed state-level food waste reduction efforts across four areas: prevention, rescue, repurposing, and recycling.  They found that recycling policies offered the most potential for diversion. Despite this, most states still fell short of the federal goal of 164 pounds per person annually. 

According to the research team, more comprehensive policies to address food waste must be implemented as soon as possible.

**********

Web Links

States Struggle to Curb Food Waste Despite Policies

Photo, posted June 28, 2021, courtesy of Ivan Radic via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Politics and plastic

By Leave a Comment

The world currently produces nearly half a billion tons of plastic each year.  This is more than twice the amount it produced 20 years ago.  Half of all plastics ever manufactured have been made in the past 20 years.  Plastic waste is everywhere.  About eight million tons of plastic waste escapes into the ocean each year.

Environmental groups have urged nations to adopt a legally binding treaty to address the ever-growing problem of plastic pollution. The United Nations climate conference in South Korea last month took up the issue of reaching agreement on such a treaty.  At what was supposed to be the final round of talks on the topic, delegates could not bridge wide differences on what such a treaty should contain.

The main bone of contention was whether the treaty should include limits on plastic production itself.  Saudi Arabia, Russia, Kuwait, and other oil-producing countries opposed any curbs on plastic production.   They also opposed the phase-out of harmful chemicals used in the production of plastic.

The Saudi delegation claimed that if the issue of plastic pollution is addressed, there should be no problem with producing plastics.  They said the problem is pollution itself, not plastics.  They proposed a focus on improving recycling and waste management.

Of course, preventing plastic pollution from occurring is an extremely challenging thing to do.  Delegates from countries pushing for a wide-ranging treaty – led by Rwanda – were unwilling to accept a toothless theory lacking real constraints on the plastics industry.

As the conference ended, delegates said that they would reconvene in future months to try again to produce a treaty.  No date or place has been announced.

**********

Web Links

Nations Fail to Reach an Agreement on Plastic Pollution

Photo, posted February 4, 2023, courtesy of Ingrid Taylar via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Increasing plastic recycling

By Leave a Comment

Recycling plastic is a complicated matter.  There are many different types of plastic and knowing which things are made of which type isn’t easy.  There are increasingly widespread recycling systems across the U.S., but the actual rates of recycling have been described as “abysmal”.

The plastic commonly used in beverage bottles is polyethylene terephthalate, or PET.  The present nationwide rate of recycling PET is about 24% and has been about at that level for a decade.

A new study by MIT has found that with a nationwide bottle deposit program, the rates could increase to 82%.  At that level, nearly two-thirds of all PET bottles could be recycled into new bottles at a net cost of just a penny a bottle.

The study looked at PET bottle collection and recycling rates in different states as well as other nations with and without bottle deposit policies, and with and without curbside recycling programs.  The study is the first to look in detail at the interplay between public policies and the detailed end-to-end aspects of the packaging, production and recycling market.

Recycling of PET is highly successful in terms of quality.  New products made from all-recycled material is virtually indistinguishable from virgin material.  The crucial bottleneck is the collection of sufficient amounts of material to meet the needs of processing plants.  So, the conclusion of the study is that with the right policies in place, significant improvements can be made.  Several European countries manage to collect more than 90% of PET bottles for recycling.  So, it can be done.

**********

Web Links

How to increase the rate of plastics recycling

Photo, posted August 10, 2013, courtesy of Lisa Risager via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The carbon cost of wind farms

By Leave a Comment

Opponents of electric vehicles and renewable energy often try to make arguments to the effect that the carbon footprint associated with producing electric cars, solar panels, and wind turbines negates their advantages over legacy technologies that involve burning fossil fuels.  These arguments have been soundly refuted for the case of electric vehicles but there have been fewer studies related to other green technologies.

A new peer-reviewed study by engineers at the Te Herenga Waka Victoria University in Wellington, New Zealand, has analyzed the carbon emissions associated with wind farm operation.

The main result is that after operating for less than two years, a wind farm can offset the carbon emissions generated across its entire 30-year lifespan.   The study takes into account everything from the manufacturing of individual turbine parts, to transporting them and installing them into place, to decommissioning the entire wind farm at its life’s end.  The environmental impacts of the installation and transportation phases are important, accounting for about 10% of the overall emissions.

The decommissioning phase is also important.  The study recommended the development of a recycling process for end-of-life turbine blades.  Currently, such blades are disposed of in landfills, but a recycling process could reduce emissions.

The manufacturing of wind turbines is the primary contributor to the carbon and energy consumption footprints and continues to be the subject of efforts to be improved.

There are other aspects of wind farms that are subject to criticism including physical impacts on the local environment and various social, wildlife and economic impacts.  But with respect to carbon emissions, wind farms are a winning strategy.

**********

Web Links

Wind Farms can Offset Their Emissions Within Two Years, New Study Shows

Photo, posted April 2, 2017, courtesy of Ian Dick via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Recycling cement

By Leave a Comment

Concrete is the second-most-used material on the planet.  Only water is used more.  Producing concrete is responsible for 7.5% of human-produced carbon dioxide emissions.  So, finding a cost-effective way to reduce these emissions is a major challenge in the face of ever-growing global demand for concrete.

Researchers at Cambridge University have found that used cement is an effective substitute for lime flux, which is an essential material used in steel recycling that results in a waste product called slag.  When lime is replaced with used cement, the end product instead is recycled cement that can be used to make new concrete.

The process does not add any significant costs to concrete or steel production and significantly reduces the emissions associated with both.

Concrete is made from sand, gravel, water, and cement.  Cement is made by a process called clinkering, in which limestone and other materials are heated to 2,600 degrees Fahrenheit.  The process converts the materials into cement but releases large amounts of CO2 as limestone decarbonates into lime. 

Cambridge researchers found that using cement clinker and iron oxide instead of lime works well in steel recycling.  Crushing old concrete and taking out the sand and stone results in a cement that is reactivated by the recycling furnace to produce a material with excellent properties. 

Recent tests by the Materials Processing Institute showed that recycled cement can be produced at scale in an electric arc furnace.  Ultimately, this method could produce zero emission cement if the electricity for the furnace comes from renewable sources.

**********

Web Links

Cement recycling method could help solve one of the world’s biggest climate challenges

Photo, posted July 18, 2011, courtesy of Kenta Mabuchi via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Ending plastic separation anxiety

By Leave a Comment

Petroleum-based plastics are one of the biggest environmental problems we face.  They mostly end up in landfills – or worse, in the oceans and elsewhere in the environment – and they basically don’t decompose over time.  Bio-based plastics were invented to help solve the plastic waste crisis.  These materials do break down in the environment providing a potential solution to the problem.  But it turns out that they can actually make plastic waste management even more challenging.

The problem is that bioplastics look and feel so similar to conventional plastics that they get mixed in with the petroleum-based plastics rather than ending up in composters, where they can break down as designed.

Mixtures of conventional and bioplastics end up in recycling streams where they get shredded and melted down, resulting in materials that are of very poor quality for making functional products.  The only solution is to try to separate the different plastics at recycling facilities, which is difficult and expensive to do.

Scientists at Lawrence Berkeley National Laboratory, the Joint BioEnergy Institute, and the incubator company X have invented a simple “one pot” process to break down mixtures of different types of plastic using naturally derived salt solutions and specialized microbes and then produce a new type of biodegradable polymer that can be made into fresh commodity products.

The team is experimenting with various catalysts to find the optimum way to break down polymers at the lowest cost and are modeling how their processes can work at the large scales of real-world recycling facilities. Chemical recycling of plastics is a hot topic but has been difficult to make happen economically at the commercial scale.

**********

Web Links

Putting an End to Plastic Separation Anxiety

Photo, posted November 28, 2016, courtesy of Leonard J Matthews via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Plastics and agriculture 

By Leave a Comment

Once celebrated as a symbol of modern innovation, plastic is now both a blessing and a curse of our time.  Since the 1950s, more than nine billion tons of plastic have been produced, and 50% of that has been during the past 15 years.  Plastic is ubiquitous in every sector, and agriculture is no different.

Modern agriculture is responsible for almost a third of global greenhouse gas emissions and is a major drain on the planet’s resources.  Modern agriculture is also inextricably linked to plastic. In fact, more than 13 million tons of plastic are used in agriculture every year.  It’s nearly impossible to imagine modern agriculture without plastics. 

But according to a new study led by researchers from Rutgers University, plastic use in agriculture must be reduced in order to mitigate pollution, and prevent toxic chemicals from leaching into the soil and adversely affecting human health. 

In the study, which was recently published in Nature Communications Earth & Environment, the researchers found that it is essential to adopt a strategic approach to mitigate plastic pollution in agriculture, including responsible usage, reduction, efficient collection, reuse, and the implementation of innovative recycling methods. 

According to the researchers, when these sustainable approaches aren’t possible, biodegradable and nontoxic bioplastics should be used.  The research team insists that environmentally benign additives should be mandated in order to reduce plastic toxicity. 

Plastic pollution is a problem that needs to be addressed in every sector. 

**********

Web Links

Plastic Use in Agriculture Must be Reduced, According to New Research

How can the use of plastics in agriculture become more sustainable?

Photo, posted November 12, 2022, courtesy of Kevin Dooley via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Recycling Solar Panels | Earth Wise

By Leave a Comment

Solar panels generally have a useful life of around 20 to 25 years.  The great majority of deployed panels have been installed fairly recently, so they have a long way to go.  But the growth in solar technology dates back to the 1990s, so there are growing number of panels that have already or are shortly coming to their end-of-life.

Today, roughly 90% of solar panels that have lost their efficiency due to age, or that are defective, end up in landfills because recycling them is too expensive.  Nevertheless, solar panels contain valuable materials, including silver, copper, and crystalline silicon, as well as lower-value aluminum and glass. 

The rapid growth of solar technology means that in the coming years, large numbers of retired solar panels will enter the waste stream.  The area covered by solar panels that are due to be retired by 2030 in the U.S. alone would cover about 3,000 football fields.  Clearly, more cost-effective recycling methods are sorely needed.

Engineers at the University of New South Wales in Sydney Australia have developed a new, more effective way of recycling solar panels that can recover silver at high efficiency.  The panel frames and glass are removed leaving just the solar cells themselves.  The cells are then crushed and sieved in a vibration container that effectively separates 99% of the materials contained in them.

Silver is the most valuable material contained in solar cells.  The Australian researchers estimate that between 5 and 10 thousand tons of silver could potentially be recycled from retired solar panels by the year 2050.  But even the other materials contained in solar panels are well worth recovering if it can be done cost-effectively.

**********

Web Links

New environmentally friendly solar panel recycling process helps recover valuable silver

Photo, posted November 22, 2008, courtesy of Oregon Department of Transportation via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Better Plastic Recycling | Earth Wise

By Leave a Comment

Many of us are careful to put our plastic trash into the appropriate recycling bins hoping that we are helping to stem the global tide of plastic waste.  But many plastics are not recyclable at all and recycling those that are is not even always a good thing.  Breaking down plastics can generate polluting microplastics that are themselves a major environmental problem.  And perhaps the biggest problem for recycling efforts is that they are not cost effective and generally incur huge losses.

Chemical engineers at the University of Wisconsin-Madison recently published a study in the journal Nature outlining a new technique for turning low-value waste plastic into high-value industrial chemicals. 

The technique makes use of two existing chemical processing techniques.  The first is pyrolysis, which is high-temperature heating in an oxygen-free environment.  Heating waste plastic in this way produces pyrolysis oil, a liquid mix of various compounds that includes large amounts of olefins.  Olefins are simple hydrocarbons that are a central building block of many chemicals and polymers.  Olefins are most often produced by energy-intensive processes like steam cracking of petroleum. 

The UW-Madison process takes the olefins and subjects them to a process called homogenous hydroformylation catalysis, which converts them into aldehydes, which can then be further reduced into important industrial chemicals. 

The payoff is that the process can take waste plastics, which are only worth about $100 a ton, and turn them into high-value chemicals worth $1,200-$6,000 a ton.  If the process can be optimized and otherwise made ready for industrial-scale use, it would be a real game-changer in the battle against plastic waste.

**********

Web Links

New recycling process could find markets for ‘junk’ plastic waste

Photo, posted September 16, 2015, courtesy of Oregon State University via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Upcycling Plastic Waste | Earth Wise

By Leave a Comment

People have generated 8 billion tons of plastic waste over time and less than 10% of it has been recycled.  Millions of tons of it escapes into the oceans.  Plastic piles up virtually everywhere on earth.

There are many approaches to dealing with the plastic waste problem and no one of them is a magic bullet.  Engineers at Stanford University have investigated the prospects for upcycling plastic waste for use in infrastructure like buildings and roads.

They used a mix of computer modeling, scientific research, experimental and field data to analyze the potential for using plastic waste in infrastructure.

Among their findings is that recycled glass fiber reinforced polymer composite – which is a tensile plastic commonly used in car, boat, and plane parts – is a promising material for reuse in buildings. 

Roads in which waste plastic is melted down and mixed with conventional paving materials are becoming more common around the world.  India has installed over 60,000 miles of these roads.  Studies show that roads containing waste plastic have the potential to perform better than conventional roads.  They can last longer, are more durable, can tolerate wide temperature swings, and are more resistant to water damage, cracking, and potholes.  Such roads rely less upon virgin fossil resources, which is obviously advantageous.

Upcycling plastic waste in infrastructure is attracting increasing interest because it creates value from something that is strictly a liability and may end up having regulatory advantages as societies move toward more environmentally friendly and sustainable policies.

**********

Web Links

Can we use plastic waste to build roads, buildings, and more?

Photo, posted October 7, 2022, courtesy of the Grand Canyon National Park via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

How Much Plastic Is Really In The Ocean? | Earth Wise

By Leave a Comment

The world has produced more than 6 billion tons of plastic to date and much of that has become waste that has not been recycled, incinerated, or otherwise properly contained.  A great deal of it has ended up in the oceans of the world.

Researchers at Kyushu University in Japan have done an analysis to assess just how much plastic has ended up in the ocean.  According to the study, nearly 28 million tons of plastic waste has entered the ocean and nearly two-thirds of that cannot be monitored.

Gli scienziati hanno dimostrato che i ricordi sono sparsi nelle connessioni neurali del corpo. Il sistema limbico svolge un ruolo importante nel funzionamento della memoria. Si trova sul Dosi di vareniclina lato interno delle regioni temporali, dove si trova l’ipotalamo. Quest’ultimo raggruppa il processo di pensiero.

Furthermore, the Kyushu analysis suggests that those 28 million tons are just the tip of the plastic waste iceberg.  Their findings are that there may be another 600 million tons of mismanaged plastic waste trapped on land – nearly 10% of all the plastic ever produced.

The study created models that simulate the processes by which plastics find their way into the ocean, get transported, and fragment into pieces.  According to their models, large plastics and smaller pieces of microplastics floating on the ocean surface each account for only about 3% of all ocean plastics.  Microplastics on beaches account for another 3%, and 23% of ocean plastic waste is larger plastic litter on the world’s shores.

These things account for only about a third of ocean plastic.  The rest of it is in locations that are impossible to monitor such as heavy plastics that settle on the seafloor because they are denser than seawater.  Half of plastic products made today are made from these heavy plastics.

Plastic pollution is not just a big problem; evidently it is a bigger problem than we thought.

**********

Web Links

Visible ocean plastics just the tip of the iceberg

Photo, posted February 28, 2010, courtesy of Kevin Krejci via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

El Paso’s Water Future | Earth Wise

By Leave a Comment

El Paso, Texas is part of the Paso del Norte region, which includes Ciudad Juarez in Mexico and Las Cruces, New Mexico.  The population on both sides of the border is booming, approaching 3 million people.  The region’s primary water source is the Rio Grande River.  But that river is declining.

Rising temperatures and decreasing rainfall have led to diminishing flow in the river.  Eighty percent of the river’s flow has historically been diverted to agriculture, but the reduced flow of the Rio Grande has forced many farmers to reduce planting or change to less water-hungry crops.  The river is expected to continue to decrease its flow as time goes by.

The city of El Paso gets 40% of its water supply directly from the Rio Grande.  Urban water authorities in the region are scrambling to find ways to provide cities with alternative supplies of water.

El Paso now gets some of its water from a desalination plant, which is the world’s largest inland municipal desalination plant.  The water comes from brackish groundwater rather than from the sea.  The briny waste from the plant is piped to an injection well many miles way and is permanently stored 4,000 feet underground.

El Paso continues to seek new water sources and reduce its water use.  It gets much of its water from wells drilled in nearby aquifers.  It is working to make this use of groundwater more sustainable.  The city recycles used residential water through its so-called purple pipe system, which cleans up waste water and delivers it for non-potable use on golf courses and park lawns. 

Like many places in the increasingly dry west, El Paso’s water future is uncertain. 

**********

Web Links

As Rio Grande Shrinks, El Paso Plans for Uncertain Water Future

Photo, posted April 29, 2018, courtesy of R. Baire via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

A Better Way To Recycle Plastics | Earth Wise

By Leave a Comment

The global accumulation of plastic waste is an ever-growing problem.  At least five billion tons of the stuff has accumulated on land and sea and is even showing up in the bodies of animals and humans.  Recycling plastic instead of making even more of it seems like an essential thing to do but it has proven to be extremely challenging.

The main problem is that plastics come in many different varieties and the ways of breaking them down into a form that can be reused are very specific to each type of plastic.  Sorting plastic waste by plastic type is extremely impractical at large scale.  Certainly, most consumers can’t do it themselves.  As a result, most plastic gathered in recycling programs ends up in landfills.

New research at MIT has developed a chemical process using a catalyst based on cobalt that is very effective at breaking down a variety of plastics, including polyethylene and polypropylene, which are the two most widely produced plastics.   The MIT process breaks plastics down into propane.  Propane can be used as a fuel or as a feedstock for making many different products, including new plastics.

Plastics are hard to recycle because their long-chain molecules are very stable and difficult to break apart.  Most chemical methods for breaking their chemical bonds produce a random mix of different molecules which would somehow have to be sorted out in order to be useful for anything.

The new process uses a catalyst called a zeolite that contains cobalt nanoparticles.  The catalyst selectively breaks down various plastic polymer molecules and turns more than 80% of them into propane.

The researchers are still studying the economics and logistics of the method, but it looks quite promising.

**********

Web Links

New process could enable more efficient plastics recycling

Photo, posted April 25, 2016, courtesy of NOAA Coral Reef Ecosystem Program via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Bidding ‘Adieu’ To Single-Use Plastics | Earth Wise

By Leave a Comment

Since the 1950s, more than nine billion tons of plastic have been produced, and 50% of that has been during the past 15 years.  While there are some use cases for plastic that are important, it generally serves as the poster child of our throwaway culture.

Plastic pollution can be found everywhere on earth, from the top of the tallest mountains to the bottom of the deepest oceans.  It’s in our food, water, and air. 

By 2040, researchers predict that there will be nearly 90 million tons of plastic pollution entering the environment each year.  By some estimates, single-use plastics account for half of all our plastic waste.    

Many cities, states, and even countries are limiting or even banning single-use plastics.  Canada recently announced a ban on single-use plastics.  The ban includes things like plastic shopping bags, cups, cutlery, straws, stirrers, and take-out food containers.

The ban will phase in over the next several years, beginning with a ban on the manufacture and import of single-use plastics by the end of this year.  Sales of these items will be prohibited in 2023, and the export of plastics will cease by the end of 2025.  

Canada’s southern neighbor, the United States, leads the world in plastic waste generation.  While some states have approved single-use plastic reforms, most of the effort at the federal level has focused on improving recycling rates.  However, a recent report from several environmental organizations found that plastic recycling rates in the U.S. have actually declined in the last several years, from an already-dismal 8.7% to less than 6%.    

Suggesting the plastic waste problem can be solved with improved recycling rates is greenwashing the issue. 

**********

Web Links

Canada is banning single-use plastics, including grocery bags and straws

Photo, posted October 31, 2011, courtesy of Mara via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

A Better Way To Recycle Plastic | Earth Wise

By Leave a Comment

The current state of plastic recycling is not very effective.  Plastic recycling is only able to replace 15-20% of the fossil-fuel-derived raw material needed to produce society’s demand for plastic.

Researchers at Chalmers University in Sweden have now demonstrated how the carbon content in mixed waste could be used to replace all of the fossil raw materials in the production of new plastic.  In principle, their technology could completely eliminate the climate impact of plastic materials.

According to the researchers, there are enough carbon atoms in waste to meet the needs of all global plastic production.

The Chalmers process is based on thermochemical technology and involves heating waste to 1100-1500 degrees Fahrenheit.  The waste is thereby vaporized and when hydrogen is added, becomes a carbon-based substance that can replace the fossil-fuel building blocks of plastic.  The method does not require sorting the waste materials.  Different types of waste, such as old plastic products and even paper cups, with or without food residues, can be fed into the recycling reactors.  The researchers are now developing the techniques required to utilize their recycling technology in the same factories in which plastic products are currently being made from fossil oil or gas.

The principle of the process is inspired by the natural carbon cycle in which plants break down into carbon dioxide when they wither and die, and then photosynthesis uses carbon dioxide and solar energy to grow new plants.

Producing new plastics would no longer require petroleum or other fossil fuels as raw materials.  If the energy needed to drive the recycling reactors is taken from renewable sources, plastics could become the basis of a sustainable and circular economy.

**********

Web Links

Pioneering recycling turns mixed waste into premium plastics with no climate impact

Photo, posted August 10, 2013, courtesy of Lisa Risager via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Plastic Recycling Isn’t Working | Earth Wise

By Leave a Comment

A recent report from several environmental organizations shows that plastic recycling rates in the U.S. have actually declined in the last several years from about 8.7% of discarded plastic to less than 6%.   Meanwhile, since 1980, per capita plastic waste generation has increased 263%, totaling 218 pounds of plastic waste per person as of 2018.

Diminishing recycling rates don’t necessarily indicate a lack of interest by the public.  Plastic recycling is a complicated process.  There are multiple types of plastic that can’t be intermingled and there are no simple and sustainable ways to recycle many forms of plastic.   On top of that, the declining recycling rate also reflects the fact that we no longer can export our plastic waste to countries like China and Turkey, which have banned U.S. waste imports.

Recycling in general is a successful practice.  Paper recycling rates are around 66% as of 2020.  Cardboard recycling was at 88.8% in 2020, and metal recycling rates range from 27% to 76%, depending on the type of metal.  Glass recycling rates are a little over 30%.  Only plastic recycling has never reached 10%, even before shipping our waste overseas and declaring it to be recycled was going on.

According to environmental organizations focused on the global plastic problem, there is no circular economy of plastics.  Perhaps if truly biodegradable plastics became practical, economical, and widely utilized, the situation would be different.  As things stand, the only solution is to reduce the production, use, and disposal of plastics.

**********

Web Links

Plastics Recycling ‘Does Not Work,’ Environmentalists Stress as U.S. Recycling Rates Drop to 5%

Photo, posted May 13, 2021, courtesy of Ivan Radic via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Recycling Shingles | Earth Wise

By Leave a Comment

Every year in the US, about 13 million tons of asphalt material is removed from old roofs to be replaced with new shingles.  Only about 10% of that is recycled for use in paving and various roadway projects.  The other 12 million tons of asphalt ends up in landfills where it takes a very long time to break down.

GAF, the largest roofing manufacturer in North America, has developed a shingle recycling process for which it has received three patents.  The process involves grinding torn-off shingles into a refined material which can then be introduced into the shingle manufacturing process.  The material – referred to as RAS for recycled asphalt shingles – has the potential to significantly reduce the amount of virgin asphalt needed to make new shingles.

Tests by GAF reclaimed upwards of 90% of the waste shingle material and produced new shingles containing up to 15% recycled content.  Underwriters Laboratories certified the shingles containing RAS material with regard to their safety and effectiveness.  The GAF process opens to door to creating a circular, sustainable economy for asphalt used for roofing shingles.

Roofs play an important role in the transition to a green economy.  Apart from recycling asphalt shingles, there are increasing options for solar shingles, which take the place of both traditional asphalt shingles and ordinary solar panels by integrating them into a single roofing product.  There are also so-called green roofs, which replace conventional roofing materials with a contained green space atop a building. Such roofs provide stormwater management, cooling, and an interesting aesthetic.

All aspects of buildings play important roles in our environment – even their roofs.

**********

Web Links

5 Ways Roofers Can Celebrate Earth Day, Everyday

Photo, posted April 15, 2012, courtesy of Robert Taylor via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

WAMC Northeast Public Radio

WAMC/Northeast Public Radio is a regional public radio network serving parts of seven northeastern states (more...)